https://xdme.com/watch-book1-q001.html https://xdme.com/book1-thumbs/page-001.jpg Why Do We Get Goosebumps? Tiny Muscles, Big Bumps! Ever felt your skin turn bumpy when you were cold or hearing a spooky story? Tiny muscles at the base of each hair, called arrector pili, pull the hair upright and push the skin up https://socialmedia.xdme.com/videos/page-001.mp4 https://www.youtube.com/embed/TIDwoiA8GAU 132 2026-09-29T15:17:04+00:00 yes https://xdme.com/watch-book1-q002.html https://xdme.com/book1-thumbs/page-002.jpg Why Does Your Heart Keep Beating While You Sleep? Your heart never takes a night off, even when you are fast asleep! It makes its own tiny electrical signal, and a small group of cells called the sinus node acts like the conductor https://socialmedia.xdme.com/videos/page-002.mp4 https://www.youtube.com/embed/E-WDD6V3Vw8 128 2026-09-29T15:17:05+00:00 yes https://xdme.com/watch-book1-q003.html https://xdme.com/book1-thumbs/page-003.jpg Why Do Onions Make You Cry? The Tiny Gas Trick! Can a vegetable really make you cry? When an onion is cut, it releases a sharp gas called syn-propanethial S-oxide, the onion's way of defending itself. The gas drifts up, mixes wi https://socialmedia.xdme.com/videos/page-003.mp4 https://www.youtube.com/embed/tXrqgdmHEtc 125 2026-09-29T15:17:07+00:00 yes https://xdme.com/watch-book1-q004.html https://xdme.com/book1-thumbs/page-004.jpg Why Do We Hiccup? Meet Your Twitchy Diaphragm! Hic! Where does that funny sound come from? A hiccup starts when your diaphragm, a big dome-shaped muscle under your lungs, suddenly twitches. Air rushes in for a super quick breat https://socialmedia.xdme.com/videos/page-004.mp4 https://www.youtube.com/embed/_y_dG1bFmJ0 121 2026-09-29T15:17:06+00:00 yes https://xdme.com/watch-book1-q005.html https://xdme.com/book1-thumbs/page-005.jpg Why Do We Sneeze? Your Nose's Super Reflex! Ah-choo! Sneezing is your body's way of protecting you. Tiny bits like dust, pollen or pepper tickle the inside of your nose, and special cells send an alert to your brain. Your br https://socialmedia.xdme.com/videos/page-005.mp4 https://www.youtube.com/embed/lzCDCz85NRE 122 2026-09-29T15:17:07+00:00 yes https://xdme.com/watch-book1-q006.html https://xdme.com/book1-thumbs/page-006.jpg Why Do We Have Fingerprints? Tiny Treads on Your Fingers! Look closely at your fingertips and you will see a swirly pattern that belongs only to you. The raised ridges help your fingers grip things, a bit like the treads on a bike tire, a https://socialmedia.xdme.com/videos/page-006.mp4 https://www.youtube.com/embed/VvU6nhnkTWM 115 2026-09-29T15:17:09+00:00 yes https://xdme.com/watch-book1-q007.html https://xdme.com/book1-thumbs/page-007.jpg Why Do Scabs Form? Your Body's Build-a-Bandage Crew! A scrape stings, but your body already has a repair plan. When skin is damaged, special cells rush in and your body weaves a net of fibrin that catches blood cells and turns into a https://socialmedia.xdme.com/videos/page-007.mp4 https://www.youtube.com/embed/PfjxpuwtFQI 120 2026-09-29T15:17:10+00:00 yes https://xdme.com/watch-book1-q008.html https://xdme.com/book1-thumbs/page-008.jpg Why Do We Have Baby Teeth? A Starter Set for Your Smile! Why do we get teeth we are going to lose? Baby teeth usually start to appear around 6 months old, and most kids end up with about 20 of them. They help you chew, speak clearly and https://socialmedia.xdme.com/videos/page-008.mp4 https://www.youtube.com/embed/AR9d0URVOZ8 112 2026-09-29T15:17:11+00:00 yes https://xdme.com/watch-book1-q009.html https://xdme.com/book1-thumbs/page-009.jpg Why Does Your Stomach Growl? The Rumbly Science! Grrrowl! Your stomach muscles squeeze in waves to mix and move food along, and these waves are called peristalsis. When your stomach is empty, the squeeze waves travel through air https://socialmedia.xdme.com/videos/page-009.mp4 https://www.youtube.com/embed/lVDd9ptaalg 125 2026-09-29T15:17:12+00:00 yes https://xdme.com/watch-book1-q010.html https://xdme.com/book1-thumbs/page-010.jpg Why Do We Need Sleep? Your Secret Superpower! Sleep might look like doing nothing, but your body and brain are hard at work. The page gives six reasons: sleep helps you learn, grow, stay healthy, feel better, focus and think, https://socialmedia.xdme.com/videos/page-010.mp4 https://www.youtube.com/embed/F0285CmskQ0 124 2026-09-29T15:17:13+00:00 yes https://xdme.com/watch-book1-q011.html https://xdme.com/book1-thumbs/page-011.jpg Why Do We Yawn? The Big Stretchy Mystery! Yawns are a big, stretchy mystery that happens to everyone. The book explains that a yawn takes a big breath of air, stretches your jaw, throat and chest, and can help you feel mor https://socialmedia.xdme.com/videos/page-011.mp4 https://www.youtube.com/embed/pGNbT4jHRtk 114 2026-09-29T15:17:14+00:00 yes https://xdme.com/watch-book1-q012.html https://xdme.com/book1-thumbs/page-012.jpg Why Is Blood Red? The Iron and Oxygen Secret! What makes blood so bright red? Blood travels around your body delivering oxygen, and inside red blood cells a protein called hemoglobin holds iron that grabs onto oxygen. When iro https://socialmedia.xdme.com/videos/page-012.mp4 https://www.youtube.com/embed/xvQJYb6Faxw 120 2026-09-29T15:17:15+00:00 yes https://xdme.com/watch-book1-q013.html https://xdme.com/book1-thumbs/page-013.jpg Why Do We Get Bruises? Purple, Green, Then Gone! Have you ever found a bruise and wondered where it came from? A bump breaks tiny blood vessels under your skin, and blood leaks into the nearby tissue, which makes the mark. Then y https://socialmedia.xdme.com/videos/page-013.mp4 https://www.youtube.com/embed/vTG8Ax4sHeo 115 2026-09-29T15:17:15+00:00 yes https://xdme.com/watch-book1-q014.html https://xdme.com/book1-thumbs/page-014.jpg Why Do Your Ears Pop on a Plane or in a Car? That funny pop in your ears is all about air pressure! When you go up high in a plane, or change height quickly on a hilly car ride, the air pressure outside changes. A small passa https://socialmedia.xdme.com/videos/page-014.mp4 https://www.youtube.com/embed/2xzcAopyW5k 125 2026-09-29T15:22:21+00:00 yes https://xdme.com/watch-book1-q015.html https://xdme.com/book1-thumbs/page-015.jpg Why Can We Taste Sweet, Salty, Sour, Bitter and Umami? Your tongue is a tiny taste lab with five special jobs! Sweet, salty, sour, bitter and umami each help you learn something about your food, from energy to salt balance to warnings https://socialmedia.xdme.com/videos/page-015.mp4 https://www.youtube.com/embed/QquZnQiQY_c 127 2026-09-29T15:22:20+00:00 yes https://xdme.com/watch-book1-q016.html https://xdme.com/book1-thumbs/page-016.jpg Why Does Food Taste Weird When You Have a Cold? Why does your favorite snack suddenly taste blah when you are stuffed up? Flavor is taste plus smell: your tongue senses sweet, salty, sour and bitter, while your nose picks up tin https://socialmedia.xdme.com/videos/page-016.mp4 https://www.youtube.com/embed/Rhd9CYBuCKA 130 2026-09-29T15:22:22+00:00 yes https://xdme.com/watch-book1-q017.html https://xdme.com/book1-thumbs/page-017.jpg Why Does Your Funny Bone Tingle? (Spoiler: It's Not a Bone!) Ouch, zing! The funny bone is not really a bone at all. It is a nickname for a spot near your elbow where the ulnar nerve runs close to the surface, in a groove near the humerus bo https://socialmedia.xdme.com/videos/page-017.mp4 https://www.youtube.com/embed/AQZlxrWJs8Q 125 2026-09-29T15:22:23+00:00 yes https://xdme.com/watch-book1-q018.html https://xdme.com/book1-thumbs/page-018.jpg Why Do We Blush? A Very Human Superpower! Have your cheeks ever turned pink when something was funny, surprising or kind? When your brain notices a strong feeling, tiny blood vessels in your cheeks open up and send extra b https://socialmedia.xdme.com/videos/page-018.mp4 https://www.youtube.com/embed/QqwplJyzTh0 125 2026-09-29T15:22:25+00:00 yes https://xdme.com/watch-book1-q019.html https://xdme.com/book1-thumbs/page-019.jpg Why Do We Have Earwax? Tiny Wax, Big Jobs! Earwax may seem yucky, but it works hard for you! It traps dust, dirt and tiny particles before they travel deep into your ear, and it helps keep the ear canal from getting too wet https://socialmedia.xdme.com/videos/page-019.mp4 https://www.youtube.com/embed/ILOpQhvzSQY 127 2026-09-29T15:22:26+00:00 yes https://xdme.com/watch-book1-q020.html https://xdme.com/book1-thumbs/page-020.jpg Why Do We Cry Tears? It's More Than Just Water! Tears do more than show feelings! They wash away dust and tiny bits to keep your eyes clean and protected. Your brain also sends out tears when you feel sad, happy or overwhelmed, https://socialmedia.xdme.com/videos/page-020.mp4 https://www.youtube.com/embed/71TZil-v7nA 128 2026-09-29T15:22:29+00:00 yes https://xdme.com/watch-book1-q021.html https://xdme.com/book1-thumbs/page-021.jpg Why Do We Need Water? Big Jobs for Tiny Cells! Grab a glass of water, because your body is counting on it! About 60 to 70 percent of your body is water, and it carries nutrients and oxygen, keeps your temperature just right, an https://socialmedia.xdme.com/videos/page-021.mp4 https://www.youtube.com/embed/QHhkEBFJoR4 123 2026-09-29T15:22:40+00:00 yes https://xdme.com/watch-book1-q022.html https://xdme.com/book1-thumbs/page-022.jpg Why Do We Get Dizzy When We Spin? Wobbly Ear Fluid! Spinning is fun until the room keeps spinning! Deep inside your ears are tiny fluid-filled loops called semicircular canals. When you spin, the fluid swirls along, and when you sto https://socialmedia.xdme.com/videos/page-022.mp4 https://www.youtube.com/embed/2m1XRpPDFuc 125 2026-09-29T15:22:27+00:00 yes https://xdme.com/watch-book1-q023.html https://xdme.com/book1-thumbs/page-023.jpg Why Do We Get Fevers? Your Body's Smart Thermostat! A fever can feel yucky, but it is not random. When germs sneak in, your brain raises your body's temperature set point, like turning up a thermostat. Many germs do not like heat, s https://socialmedia.xdme.com/videos/page-023.mp4 https://www.youtube.com/embed/f_3QYywdzso 127 2026-09-29T15:22:28+00:00 yes https://xdme.com/watch-book1-q024.html https://xdme.com/book1-thumbs/page-024.jpg Why Do We Have Two Eyes? The Secret of Depth! Two eyes are better than one, and here is why. Each eye sees the world from a slightly different spot, a few centimeters apart, and your brain stacks the two views together to buil https://socialmedia.xdme.com/videos/page-024.mp4 https://www.youtube.com/embed/55ZW1yV9NM8 124 2026-09-29T15:22:31+00:00 yes https://xdme.com/watch-book1-q025.html https://xdme.com/book1-thumbs/page-025.jpg Why Do Fingers Wrinkle in the Bath? Built-In Tire Treads! Pruney fingers are not just soggy skin! The page explains that nerves tell the blood vessels in your fingertips to narrow, which pulls the skin inward and makes wrinkles. Those wri https://socialmedia.xdme.com/videos/page-025.mp4 https://www.youtube.com/embed/E5Y5Ft3c_XE 130 2026-09-29T15:22:33+00:00 yes https://xdme.com/watch-book1-q026.html https://xdme.com/book1-thumbs/page-026.jpg Why Can't You Tickle Yourself? Your Brain Saw It Coming! Go ahead and try to tickle yourself. It does not work! Tickling needs surprise, and your brain is a super predictor that knows the movement, speed and pressure of your own hand. Be https://socialmedia.xdme.com/videos/page-026.mp4 https://www.youtube.com/embed/GpueW66wngo 130 2026-09-29T15:22:32+00:00 yes https://xdme.com/watch-book1-q027.html https://xdme.com/book1-thumbs/page-027.jpg Why Do We Have Eyebrows? More Than Just Face Fuzz! Your eyebrows have three big jobs. They channel sweat toward the sides of your face so it stays out of your eyes, and they act like a natural shield against rain and moisture. They https://socialmedia.xdme.com/videos/page-027.mp4 https://www.youtube.com/embed/ep7h5y3Fisg 127 2026-09-29T15:22:34+00:00 yes https://xdme.com/watch-book1-q028.html https://xdme.com/book1-thumbs/page-028.jpg Why Do We Shiver? Your Muscles Make Heat! Brrr! Shivering is not random, it is your body's smart plan. When your body senses cold, your brain tells your muscles to twitch back and forth on purpose. That twitching uses ener https://socialmedia.xdme.com/videos/page-028.mp4 https://www.youtube.com/embed/h4929W4gnnc 122 2026-09-29T15:22:35+00:00 yes https://xdme.com/watch-book1-q029.html https://xdme.com/book1-thumbs/page-029.jpg Why Do We Sweat? Your Built-In Cooling System! Sweat is your body's natural cooling system. When you get hot, sweat comes out onto your skin from tiny sweat glands, and as the liquid evaporates into water vapor it carries heat https://socialmedia.xdme.com/videos/page-029.mp4 https://www.youtube.com/embed/qZ4v_YCjgXc 123 2026-09-29T15:22:37+00:00 yes https://xdme.com/watch-book1-q030.html https://xdme.com/book1-thumbs/page-030.jpg Why Do We Get Growing Pains? Achy Legs Explained! Growing pains are real aches, but the page says they are not an injury. They often show up as tired leg muscles after busy play, commonly at night in both legs, and are usually gon https://socialmedia.xdme.com/videos/page-030.mp4 https://www.youtube.com/embed/-Wd4zUgK8F0 122 2026-09-29T15:22:36+00:00 yes https://xdme.com/watch-book1-q031.html https://xdme.com/book1-thumbs/page-031.jpg Why Do Cats Purr? The Rumble in the Voice Box! A cat's purr is a steady, soothing rumble, and it comes from the voice box, or larynx. Tiny muscles there vibrate quickly, and the purr happens as the cat breathes in and out. The https://socialmedia.xdme.com/videos/page-031.mp4 https://www.youtube.com/embed/fJ9j2gDdmpc 128 2026-09-29T15:22:38+00:00 yes https://xdme.com/watch-book1-q032.html https://xdme.com/book1-thumbs/page-032.jpg Why Do Bees Dance? The Waggle Dance Explained! Bees can share directions with a dance! When a scout bee finds flowers, she returns to the hive and dances a figure eight. The straight middle part, called the waggle run, shows th https://socialmedia.xdme.com/videos/page-032.mp4 https://www.youtube.com/embed/1_AOg_aokRk 128 2026-09-29T15:22:39+00:00 yes https://xdme.com/watch-book1-q033.html https://xdme.com/book1-thumbs/page-033.jpg Why Don't Woodpeckers Get Headaches? A Built-In Helmet! Woodpeckers can peck thousands of times a day and stay headache-free, and the page shows why. Their skulls are full of tiny spaces that cushion the brain like a natural shock absor https://socialmedia.xdme.com/videos/page-033.mp4 https://www.youtube.com/embed/xmBzDO1spNk 132 2026-09-29T15:22:41+00:00 yes https://xdme.com/watch-book1-q034.html https://xdme.com/book1-thumbs/page-034.jpg Why Do Dogs Tilt Their Heads? Clues From a Curious Pup! When your dog tilts its head, it may be trying to see and hear better. A long muzzle can get in the way of what is straight ahead, and a tilt moves it aside for a clearer view. The https://socialmedia.xdme.com/videos/page-034.mp4 https://www.youtube.com/embed/EiR2LGuUcUQ 122 2026-09-29T15:22:42+00:00 yes https://xdme.com/watch-book1-q035.html https://xdme.com/book1-thumbs/page-035.jpg Why Are Flamingos Pink? It Starts With Their Dinner! Flamingo chicks are not born pink, they start out fluffy and light grey. Flamingos eat shrimp and algae rich in carotenoids, which are natural pigments, and the pigment settles in https://socialmedia.xdme.com/videos/page-035.mp4 https://www.youtube.com/embed/WVgjYd1O0Rk 140 2026-09-29T15:22:43+00:00 yes https://xdme.com/watch-book1-q036.html https://xdme.com/book1-thumbs/page-036.jpg Why Do Chameleons Change Color? It's More Than Hiding! Chameleons do not just change color to hide. Their skin has stacked layers, like a tiny living sandwich, and cells in the layers tilt and stretch like blinds on a window, changing https://socialmedia.xdme.com/videos/page-036.mp4 https://www.youtube.com/embed/vb_Epxovd_w 139 2026-09-29T15:37:22+00:00 yes https://xdme.com/watch-book1-q037.html https://xdme.com/book1-thumbs/page-037.jpg Why Can Owls Turn Their Heads So Far? Owls can look behind them without moving their bodies! Their tube-shaped eyes barely roll in their sockets, so they turn the whole head instead. Owls have extra neck bones, about 1 https://socialmedia.xdme.com/videos/page-037.mp4 https://www.youtube.com/embed/jpouN7wC4hw 134 2026-09-29T15:22:44+00:00 yes https://xdme.com/watch-book1-q038.html https://xdme.com/book1-thumbs/page-038.jpg Why Do Sharks Have So Many Teeth? A Conveyor Belt of Chompers! Sharks are tooth experts! Their teeth are tools that fall out when worn or loose, and behind the front teeth are backup rows waiting their turn, like a conveyor belt. When a front https://socialmedia.xdme.com/videos/page-038.mp4 https://www.youtube.com/embed/WhG8QsOnB_E 131 2026-09-29T15:22:45+00:00 yes https://xdme.com/watch-book1-q039.html https://xdme.com/book1-thumbs/page-039.jpg Why Do Whales Sing? Songs That Travel for Miles! Whale songs are some of the ocean's most amazing sounds! Sound travels far in water, and the page says whale songs can travel for miles. Male humpbacks sing complex, patterned song https://socialmedia.xdme.com/videos/page-039.mp4 https://www.youtube.com/embed/hgsb86qnivU 140 2026-09-29T15:22:46+00:00 yes https://xdme.com/watch-book1-q040.html https://xdme.com/book1-thumbs/page-040.jpg Why Do Penguins Huddle? Teamwork Keeps Them Warm! Penguins have a clever plan for staying warm in the cold. Wind steals body heat, so they gather in a tight circle where the birds on the outside block the wind for the group. They https://socialmedia.xdme.com/videos/page-040.mp4 https://www.youtube.com/embed/Mq-GoxnSZeo 126 2026-09-29T15:17:16+00:00 yes https://xdme.com/watch-book1-q041.html https://xdme.com/book1-thumbs/page-041.jpg Why Is Spider Silk So Strong? Spiders' Super Thread! Spider silk starts out as a liquid protein inside the spider's gland. As it is pulled into a fiber, the protein molecules line up and lock together, making a strong thread. Spiders https://socialmedia.xdme.com/videos/page-041.mp4 https://www.youtube.com/embed/MZKoEjXRPlY 131 2026-09-29T15:17:17+00:00 yes https://xdme.com/watch-book1-q042.html https://xdme.com/book1-thumbs/page-042.jpg Why Do Butterfly Wings Have Colors? Paint vs. Tiny Mirrors! Butterfly colors come from two tricks. Some color is pigment, which is like nature's paint that soaks into things. The brightest blues and greens often come from tiny overlapping s https://socialmedia.xdme.com/videos/page-042.mp4 https://www.youtube.com/embed/zxC3Rs2OWk0 130 2026-09-29T15:17:19+00:00 yes https://xdme.com/watch-book1-q043.html https://xdme.com/book1-thumbs/page-043.jpg Why Do Camels Have Humps? It's Not What You Think! Many people think a camel's hump holds water, but the page says it does not. The hump is a fat backpack, and keeping fat in one place helps the rest of the body dump heat in the ho https://socialmedia.xdme.com/videos/page-043.mp4 https://www.youtube.com/embed/ZPLs_RuX1_o 131 2026-09-29T15:22:52+00:00 yes https://xdme.com/watch-book1-q044.html https://xdme.com/book1-thumbs/page-044.jpg Why Do Cows Have Four Stomach Rooms? A Tiny Teamwork Tummy! A cow's stomach is a four-room digestion system! Grass is made of tough cellulose, so cows rely on billions of microbes in the rumen, the microbe kitchen, to break it down. Then co https://socialmedia.xdme.com/videos/page-044.mp4 https://www.youtube.com/embed/XIhQJU8lqgs 124 2026-09-29T15:17:23+00:00 yes https://xdme.com/watch-book1-q045.html https://xdme.com/book1-thumbs/page-045.jpg Why Can Snakes Swallow Big Prey? Jaws That Walk! Snakes can swallow animals wider than their heads thanks to some super clever skull and jaw features. A snake's skull bones are loosely connected, so the head can stretch, and the https://socialmedia.xdme.com/videos/page-045.mp4 https://www.youtube.com/embed/N_UP_HP7mwY 124 2026-09-29T15:17:25+00:00 yes https://xdme.com/watch-book1-q046.html https://xdme.com/book1-thumbs/page-046.jpg Why Do Bats Use Sound to Hunt? Echoes in the Dark! Night is hard to hunt in by eye, so bats use sound! They make high-pitched clicks with their mouth or nose, and the clicks bounce back as echoes. The echoes work like a moving map, https://socialmedia.xdme.com/videos/page-046.mp4 https://www.youtube.com/embed/7kJCwc_st-U 113 2026-09-29T15:17:26+00:00 yes https://xdme.com/watch-book1-q047.html https://xdme.com/book1-thumbs/page-047.jpg Why Do Octopuses Seem So Smart? Eight Clever Arms! Octopuses have big brains for invertebrates, which helps them learn, remember and solve problems. Their arms are packed with neurons, so the arms can act on their own, and special https://socialmedia.xdme.com/videos/page-047.mp4 https://www.youtube.com/embed/B-ioW9DmbD0 124 2026-09-29T15:17:27+00:00 yes https://xdme.com/watch-book1-q048.html https://xdme.com/book1-thumbs/page-048.jpg Why Do Fireflies Light Up? A Cold, Glowing Code! Fireflies make light right inside their bodies! Special chemicals called luciferin and luciferase mix with oxygen in the abdomen to create a glow. It is a cold light with almost no https://socialmedia.xdme.com/videos/page-048.mp4 https://www.youtube.com/embed/L-4IOHgzNMk 128 2026-09-29T15:58:06+00:00 yes https://xdme.com/watch-book1-q049.html https://xdme.com/book1-thumbs/page-049.jpg Why Do Ants Follow a Trail? A Secret Scent Path! When an ant finds food, she lays down a scent trail to tell her sisters. The other ants follow the pheromones, the chemical scent, straight to the food. When the food is gone, the https://socialmedia.xdme.com/videos/page-049.mp4 https://www.youtube.com/embed/aeI1QjX6C4g 121 2026-09-29T15:37:21+00:00 yes https://xdme.com/watch-book1-q050.html https://xdme.com/book1-thumbs/page-050.jpg Why Do Zebras Have Stripes? Scientists Are Still Asking! Scientists still argue about why zebras have stripes, and there is no single answer everyone agrees on yet. One idea is that stripes seem to confuse biting flies, which have a hard https://socialmedia.xdme.com/videos/page-050.mp4 https://www.youtube.com/embed/PzkX5bdDUkk 131 2026-09-29T16:16:48+00:00 yes https://xdme.com/watch-book1-q051.html https://xdme.com/book1-thumbs/page-051.jpg Why Is the Sky Blue? A Trick Light Plays in the Air! Look up on a sunny day and you are seeing a cool trick of light. Sunlight looks white, but it is made of all colors mixed together. When it passes through the air, tiny bits of air https://socialmedia.xdme.com/videos/page-051.mp4 https://www.youtube.com/embed/kBo91JskM-A 124 2026-09-29T15:57:35+00:00 yes https://xdme.com/watch-book1-q052.html https://xdme.com/book1-thumbs/page-052.jpg Why Do Volcanoes Erupt? Melted Rock Under Pressure! Deep underground it is super hot, so rocks melt and become magma. Gases in the magma form bubbles that squeeze together and build pressure. When the pressure gets too high, magma p https://socialmedia.xdme.com/videos/page-052.mp4 https://www.youtube.com/embed/viy4sP9DYP0 124 2026-09-29T16:29:26+00:00 yes https://xdme.com/watch-book1-q053.html https://xdme.com/book1-thumbs/page-053.jpg Why Do Seasons Change? It's All About Earth's Tilt! Summer, fall, winter and spring happen because Earth is tilted as it travels around the Sun. The tilt aims one half of Earth toward the Sun for part of the year, and more direct su https://socialmedia.xdme.com/videos/page-053.mp4 https://www.youtube.com/embed/AyiIdbEhUns 139 2026-09-29T16:16:17+00:00 yes https://xdme.com/watch-book1-q054.html https://xdme.com/book1-thumbs/page-054.jpg Why Does It Rain? Follow the Water Cycle! Rain is one stop on the water cycle! The Sun heats water in oceans, lakes and rivers, and it turns into invisible vapor that rises into the air. Up high, the vapor cools into tiny https://socialmedia.xdme.com/videos/page-054.mp4 https://www.youtube.com/embed/ysZ-IGuYu70 130 2026-09-29T16:41:31+00:00 yes https://xdme.com/watch-book1-q055.html https://xdme.com/book1-thumbs/page-055.jpg Why Does Thunder Follow Lightning? Light Wins the Race! Flash first, boom later! A lightning bolt is super hot and heats the air around it to hotter than the surface of the Sun. That air expands fast and explodes outward in a shock wave https://socialmedia.xdme.com/videos/page-055.mp4 https://www.youtube.com/embed/xejdid5_S6M 138 2026-09-29T16:29:27+00:00 yes https://xdme.com/watch-book1-q056.html https://xdme.com/book1-thumbs/page-056.jpg Why Do Rainbows Appear? Light Bends and Splits! Rainbows look like magic, but they come from light, water and a little science. Sunlight shines into tiny drops of water in the air, bends and splits into all its colors, and you s https://socialmedia.xdme.com/videos/page-056.mp4 https://www.youtube.com/embed/MdJcvfLI4qk 128 2026-09-29T16:56:40+00:00 yes https://xdme.com/watch-book1-q057.html https://xdme.com/book1-thumbs/page-057.jpg Why Do Earthquakes Happen? Slipping Slabs of Rock! Earthquakes begin deep underground when huge slabs of rock called plates move very slowly. Sometimes the plates get stuck at a fault while the force keeps pushing, so stress builds https://socialmedia.xdme.com/videos/page-057.mp4 https://www.youtube.com/embed/9okVPGwIl2Y 126 2026-09-29T16:42:02+00:00 yes https://xdme.com/watch-book1-q058.html https://xdme.com/book1-thumbs/page-058.jpg Why Do Tides Rise and Fall? The Moon's Big Pull! Twice a day, the ocean creeps up the beach and then slides back out. The Moon's gravity pulls on Earth's oceans and makes water bulge, with one bulge on the side facing the Moon an https://socialmedia.xdme.com/videos/page-058.mp4 https://www.youtube.com/embed/Y2O_H2jAoi4 127 2026-09-29T17:09:16+00:00 yes https://xdme.com/watch-book1-q059.html https://xdme.com/book1-thumbs/page-059.jpg Why Do Rivers Flow to the Sea? Water Always Runs Downhill! Rivers start small! Raindrops on a hillside trickle into tiny rills, rills join to become streams, and streams merge into rivers, all because water runs downhill. Oceans sit at the https://socialmedia.xdme.com/videos/page-059.mp4 https://www.youtube.com/embed/3E1HR8Q8HZc 133 2026-09-29T16:57:11+00:00 yes https://xdme.com/watch-book1-q060.html https://xdme.com/book1-thumbs/page-060.jpg Why Do Mountains Exist? Three Ways to Build a Peak! Mountains form in different ways, and the page gives three cool reasons. Plates of Earth's crust can collide and crumple, folding land upward. Volcanoes can pile up layers of lava https://socialmedia.xdme.com/videos/page-060.mp4 https://www.youtube.com/embed/ivQeUJ2i3b8 129 2026-09-29T17:23:53+00:00 yes https://xdme.com/watch-book1-q061.html https://xdme.com/book1-thumbs/page-061.jpg Why Are Deserts So Dry? Three Big Reasons! Deserts are not just hot, they are super dry! The page gives three big reasons: they get very little rain, often less than about 10 inches a year; mountains can cause a rain shadow https://socialmedia.xdme.com/videos/page-061.mp4 https://www.youtube.com/embed/AC8hZR5xAv8 128 2026-09-29T17:09:48+00:00 yes https://xdme.com/watch-book1-q062.html https://xdme.com/book1-thumbs/page-062.jpg Why Do We Find Fossils? It Takes a Little Luck! Fossils are the preserved remains or traces of ancient life, but not everything becomes one. When a plant or animal dies, its soft parts usually rot away. If the remains are buried https://socialmedia.xdme.com/videos/page-062.mp4 https://www.youtube.com/embed/mIfTcwzjlS4 130 2026-09-29T17:38:02+00:00 yes https://xdme.com/watch-book1-q063.html https://xdme.com/book1-thumbs/page-063.jpg Why Does Soil Matter? The Ground Is Full of Life! Soil is more than dirt! It starts with broken rock crumbs mixed with air, water and tiny living things. Soil holds water and nutrients so plant roots can soak them up and grow stro https://socialmedia.xdme.com/videos/page-063.mp4 https://www.youtube.com/embed/vojsPm66nXM 131 2026-09-29T17:24:24+00:00 yes https://xdme.com/watch-book1-q064.html https://xdme.com/book1-thumbs/page-064.jpg Why Do Caves Form? Rain, Rock and Slow Drips! Caves are nature's underground architecture. Rain picks up carbon dioxide and becomes a weak carbonic acid, which seeps into the ground and slowly dissolves limestone along cracks https://socialmedia.xdme.com/videos/page-064.mp4 https://www.youtube.com/embed/cmfJMkK-aAs 134 2026-10-03T21:04:44+00:00 yes https://xdme.com/watch-book1-q065.html https://xdme.com/book1-thumbs/page-065.jpg Why Is Quicksand Not a Movie Deathtrap? Science Has the Story! Movies make quicksand look scary, but science has the real story. Quicksand is sand mixed with water, which can act like a thick, goopy liquid. The page says you float more easily https://socialmedia.xdme.com/videos/page-065.mp4 https://www.youtube.com/embed/fQtLpYVfEsI 134 2026-09-29T17:38:33+00:00 yes https://xdme.com/watch-book1-q066.html https://xdme.com/book1-thumbs/page-066.jpg Why Do the Northern Lights Glow? A Sky Full of Color! The Northern Lights are a glowing show high in the sky. The Sun sends out streams of charged particles, and Earth's magnetic field acts like an invisible shield that guides them to https://socialmedia.xdme.com/videos/page-066.mp4 https://www.youtube.com/embed/5MlKbl3qkmA 132 2026-10-03T21:07:48+00:00 yes https://xdme.com/watch-book1-q067.html https://xdme.com/book1-thumbs/page-067.jpg Why Do Hurricanes Spin? Ocean Heat and Earth's Twist! Hurricanes are powered by warm ocean water. Heat makes moist air rise, which creates low pressure, and cooler air rushes in to take its place. Earth's rotation makes the winds curv https://socialmedia.xdme.com/videos/page-067.mp4 https://www.youtube.com/embed/yFzv5btzvL4 136 2026-10-03T21:10:52+00:00 yes https://xdme.com/watch-book1-q068.html https://xdme.com/book1-thumbs/page-068.jpg Why Is Every Snowflake Different? One of a Kind! Snowflakes all follow one family rule but each one turns out different. A snowflake begins as a tiny ice crystal in a cloud and grows by collecting water vapor as it falls. Changes https://socialmedia.xdme.com/videos/page-068.mp4 https://www.youtube.com/embed/0nMB0nuV-40 132 2026-10-03T21:13:13+00:00 yes https://xdme.com/watch-book1-q069.html https://xdme.com/book1-thumbs/page-069.jpg Why Do Clouds Stay Up? They're Made of Tiny Drops! Clouds look like fluffy cotton, but they are made of billions of tiny water droplets. Warm air rising from the ground helps hold those tiny droplets up. When the droplets join toge https://socialmedia.xdme.com/videos/page-069.mp4 https://www.youtube.com/embed/G-wcl188ZE8 129 2026-10-03T21:16:28+00:00 yes https://xdme.com/watch-book1-q070.html https://xdme.com/book1-thumbs/page-070.jpg Why Is Lightning So Hot? Big Energy in a Tiny Strike! Lightning is a giant electric current that races through the air in an extremely narrow channel. The page says that channel can reach about 30,000 degrees C (54,000 degrees F). The https://socialmedia.xdme.com/videos/page-070.mp4 https://www.youtube.com/embed/bIb05RknTpE 129 2026-10-03T21:19:30+00:00 yes https://xdme.com/watch-book1-q071.html https://xdme.com/book1-thumbs/page-071.jpg Why Do Canyons Get So Deep? Rivers, Rock and Rising Land! Canyons are amazing cuts in the land. Rivers start small, but over time moving water wears away rock and soil, and the land beneath can slowly lift upward, so the river carves even https://socialmedia.xdme.com/videos/page-071.mp4 https://www.youtube.com/embed/Pct-tCVxMl4 127 2026-10-03T21:23:27+00:00 yes https://xdme.com/watch-book1-q072.html https://xdme.com/book1-thumbs/page-072.jpg Why Do Geysers Shoot? Nature's Underground Plumbing! A geyser is nature's underground plumbing at work! Rain and snowmelt seep deep underground through cracks and porous rock, and the water gets trapped in chambers where it heats way https://socialmedia.xdme.com/videos/page-072.mp4 https://www.youtube.com/embed/l45GNYw0Oso 135 2026-10-03T21:26:29+00:00 yes https://xdme.com/watch-book1-q073.html https://xdme.com/book1-thumbs/page-073.jpg Why Does Compost Get Warm? Tiny Life, Big Heat! A compost pile can be warm even on a cool morning, and tiny living things are the reason. Bacteria and fungi break down food scraps, leaves and yard waste, and as they munch they r https://socialmedia.xdme.com/videos/page-073.mp4 https://www.youtube.com/embed/E1NkFTlBfa8 129 2026-10-03T21:29:02+00:00 yes https://xdme.com/watch-book1-q074.html https://xdme.com/book1-thumbs/page-074.jpg Why Do We Have Day and Night? Earth's Big Spin! Day and night come from Earth spinning like a giant top. One full spin takes about 24 hours, and the half of Earth facing the Sun has daytime while the other half is in shadow. Sun https://socialmedia.xdme.com/videos/page-074.mp4 https://www.youtube.com/embed/CAIZpEwlzhI 125 2026-10-03T21:31:35+00:00 yes https://xdme.com/watch-book1-q075.html https://xdme.com/book1-thumbs/page-075.jpg Why Should We Care About This Planet? Small Choices Matter! Our planet is full of amazing places, and each one is important. The page explains that weather is the day's mood while climate is the long habit, the usual pattern of weather in a https://socialmedia.xdme.com/videos/page-075.mp4 https://www.youtube.com/embed/Qm35JSSvD60 129 2026-10-03T21:34:07+00:00 yes https://xdme.com/watch-book1-q076.html https://xdme.com/book1-thumbs/page-076.jpg What If You Got Too Close to the Sun? The Sun is a giant hot ball of gas, and heat and radiation rise fast the closer you get. That is why spacecraft stay far away and use shields. The page says the Sun's surface is ab https://socialmedia.xdme.com/videos/page-076.mp4 https://www.youtube.com/embed/WyjU0MQmAMg 134 2026-10-03T21:36:40+00:00 yes https://xdme.com/watch-book1-q077.html https://xdme.com/book1-thumbs/page-077.jpg Is the Sun the Biggest Star? Sizes in Space! Our Sun looks huge, but is it the biggest star? The page says it is only medium-sized compared with other stars. Red dwarfs are the most common stars and are much smaller and coole https://socialmedia.xdme.com/videos/page-077.mp4 https://www.youtube.com/embed/f5bOpdJ5XHU 129 2026-10-03T21:40:03+00:00 yes https://xdme.com/watch-book1-q078.html https://xdme.com/book1-thumbs/page-078.jpg How Does the Sun Help Life on Earth? The Sun does much more than light up our days. It gives us light and heat that keep Earth warm and cozy, and plants use sunlight, water and air to make their own food in a process https://socialmedia.xdme.com/videos/page-078.mp4 https://www.youtube.com/embed/PxWzWfNIfbU 138 2026-10-03T21:43:06+00:00 yes https://xdme.com/watch-book1-q079.html https://xdme.com/book1-thumbs/page-079.jpg Why Does the Moon Change Shape? Slices of Sunlit Moon! The Moon looks different night after night, but it is always a big rocky ball. The Sun lights one side of the Moon while the other side stays dark, and as the Moon orbits Earth we https://socialmedia.xdme.com/videos/page-079.mp4 https://www.youtube.com/embed/08FJdvBDJ7E 126 2026-10-03T21:46:09+00:00 yes https://xdme.com/watch-book1-q080.html https://xdme.com/book1-thumbs/page-080.jpg Why Do Stars Twinkle? Wiggly Air Between Us and Space! Light from a star starts as a tiny point far out in space. When it passes through layers of moving air in Earth's atmosphere, the air bends and wiggles the light, and that is the t https://socialmedia.xdme.com/videos/page-080.mp4 https://www.youtube.com/embed/H_l1qTAHQNQ 128 2026-10-03T21:49:01+00:00 yes https://xdme.com/watch-book1-q081.html https://xdme.com/book1-thumbs/page-081.jpg Why Is Space Black? A Big Question With a Bright Answer! Space is full of stars, so why is it black? The page explains that space has almost no air, and light travels in straight lines until it hits tiny bits, like air molecules, that sc https://socialmedia.xdme.com/videos/page-081.mp4 https://www.youtube.com/embed/pylftYlls58 137 2026-10-03T21:51:33+00:00 yes https://xdme.com/watch-book1-q082.html https://xdme.com/book1-thumbs/page-082.jpg Why Do We Orbit the Sun Instead of Falling In? The Sun's gravity pulls on Earth like an invisible tug, so why do we not fall straight in? Because Earth is also zooming sideways through space. Falling toward the Sun while moving https://socialmedia.xdme.com/videos/page-082.mp4 https://www.youtube.com/embed/kPtX9QgL5tk 133 2026-10-03T21:54:36+00:00 yes https://xdme.com/watch-book1-q083.html https://xdme.com/book1-thumbs/page-083.jpg Why Do Astronauts Float? They're Falling Around Earth! Astronauts float, but there is still gravity in space! The page explains that it is gravity that keeps the space station in orbit. The station moves forward so fast that as it fall https://socialmedia.xdme.com/videos/page-083.mp4 https://www.youtube.com/embed/_-FPGxw3fcI 145 2026-10-03T22:06:00+00:00 yes https://xdme.com/watch-book1-q084.html https://xdme.com/book1-thumbs/page-084.jpg Why Do Eclipses Happen? Shadows in Space! Eclipses are shadows in space. In a solar eclipse, the Moon passes between Earth and the Sun and casts a shadow on Earth, and in a lunar eclipse, Earth passes between the Sun and t https://socialmedia.xdme.com/videos/page-084.mp4 https://www.youtube.com/embed/stZvZTv0Nd8 141 2026-10-03T22:12:21+00:00 yes https://xdme.com/watch-book1-q085.html https://xdme.com/book1-thumbs/page-085.jpg Why Is Mars Rusty Red? Iron, Oxygen and Dust! Mars is called the red planet, and the page says it is covered in iron rust. Mars is full of rocks and dust that contain iron, and when iron meets a little oxygen and water, even t https://socialmedia.xdme.com/videos/page-085.mp4 https://www.youtube.com/embed/gBe0bthT-rQ 133 2026-10-03T22:15:53+00:00 yes https://xdme.com/watch-book1-q086.html https://xdme.com/book1-thumbs/page-086.jpg Why Does Saturn Have Rings? Ice, Rock and Gravity! Saturn's rings are one of the coolest features in space. They are made of billions of pieces, from tiny dust to large boulders, mostly water ice with some rock. The pieces orbit Sa https://socialmedia.xdme.com/videos/page-086.mp4 https://www.youtube.com/embed/OKD9ceme1_g 139 2026-10-03T22:19:43+00:00 yes https://xdme.com/watch-book1-q087.html https://xdme.com/book1-thumbs/page-087.jpg Why Do Comets Grow Tails? A Dirty Snowball Meets the Sun! A comet is like a dirty snowball from space, made of ice, dust and rock. When a comet gets close to the Sun, the heat turns ice into gas and releases dust, and solar wind, a stream https://socialmedia.xdme.com/videos/page-087.mp4 https://www.youtube.com/embed/vfCWZ2fzzpk 134 2026-09-29T15:22:57+00:00 yes https://xdme.com/watch-book1-q088.html https://xdme.com/book1-thumbs/page-088.jpg Meteor or Meteorite? Learn the Space Rock Difference! Three space-rock words can be confusing, so let's break them down. A meteoroid is a small rocky or metallic object traveling through space. A meteor is the bright streak of light y https://socialmedia.xdme.com/videos/page-088.mp4 https://www.youtube.com/embed/BBJB8DTXaWc 122 2026-09-29T15:22:47+00:00 yes https://xdme.com/watch-book1-q089.html https://xdme.com/book1-thumbs/page-089.jpg Why Do We Draw Constellations? Stars, Stories and Maps! Constellations are pictures we imagine in the night sky. The page explains that stars in a constellation are not really connected, since they are huge distances apart, and we draw https://socialmedia.xdme.com/videos/page-089.mp4 https://www.youtube.com/embed/2Lqb4gIbIKA 130 2026-09-29T15:22:49+00:00 yes https://xdme.com/watch-book1-q090.html https://xdme.com/book1-thumbs/page-090.jpg Why Do We Have Leap Years? That Extra Quarter Day! A year on Earth is about 365 and a quarter days, and that extra quarter adds up. Every four years, we add an extra day, February 29, which keeps the seasons in place. The page adds https://socialmedia.xdme.com/videos/page-090.mp4 https://www.youtube.com/embed/Kze0rCFAMSI 123 2026-09-29T15:22:50+00:00 yes https://xdme.com/watch-book1-q091.html https://xdme.com/book1-thumbs/page-091.jpg Why Do Telescopes Help? Seeing Far Into Space! Telescopes help us see far into space, way beyond what our eyes can see on their own. They use large mirrors or lenses to gather much more light than an eye can, then bend and focu https://socialmedia.xdme.com/videos/page-091.mp4 https://www.youtube.com/embed/cZC7l68b0mY 132 2026-09-29T15:23:03+00:00 yes https://xdme.com/watch-book1-q092.html https://xdme.com/book1-thumbs/page-092.jpg Why Do Space Suits Look Puffy? A Wearable Atmosphere! Space suits look puffy for a good reason. Space has almost no air pressure, and the page warns that without pressure everything would swell or pop. The suit works like a wearable a https://socialmedia.xdme.com/videos/page-092.mp4 https://www.youtube.com/embed/pij1SpVdJFo 135 2026-09-29T15:23:02+00:00 yes https://xdme.com/watch-book1-q093.html https://xdme.com/book1-thumbs/page-093.jpg Why Doesn't the Moon Fall Down? It's Falling Around Us! Earth's gravity pulls on the Moon all the time, so why does the Moon not crash into us? The Moon is also zooming sideways very fast, and its sideways speed is just right. Instead o https://socialmedia.xdme.com/videos/page-093.mp4 https://www.youtube.com/embed/6my-_pqv5zs 132 2026-09-29T15:22:51+00:00 yes https://xdme.com/watch-book1-q094.html https://xdme.com/book1-thumbs/page-094.jpg What Is Gravity in Kid Words? An Invisible Pull! Gravity is an invisible pull between things with mass, and mass is stuff, anything that takes up space. The bigger an object is and the closer it is, the stronger its pull. Gravity https://socialmedia.xdme.com/videos/page-094.mp4 https://www.youtube.com/embed/opBlvYubGBI 127 2026-09-29T15:22:53+00:00 yes https://xdme.com/watch-book1-q095.html https://xdme.com/book1-thumbs/page-095.jpg What Is a Light-Year? It's Distance, Not Time! A light-year sounds like a length of time, but it is really a distance. It is how far light travels in one year, and the page says light zips through space at 300,000 kilometers pe https://socialmedia.xdme.com/videos/page-095.mp4 https://www.youtube.com/embed/QH_gihs4k3A 127 2026-09-29T15:22:55+00:00 yes https://xdme.com/watch-book1-q096.html https://xdme.com/book1-thumbs/page-096.jpg Why Do We Only See One Face of the Moon? No matter when you look, you see the same face of the Moon. The Moon does spin, but it spins once for every trip around Earth, so the same side always faces us. The page says the f https://socialmedia.xdme.com/videos/page-096.mp4 https://www.youtube.com/embed/gaVvmc0yoek 128 2026-09-29T15:22:56+00:00 yes https://xdme.com/watch-book1-q097.html https://xdme.com/book1-thumbs/page-097.jpg Why Does the Night Sky Change Through the Year? The stars you see at night are not the same all year long. Earth travels around the Sun once every year, so our viewpoint in space changes, and the night side of Earth points towar https://socialmedia.xdme.com/videos/page-097.mp4 https://www.youtube.com/embed/NoNaYsGCP1I 131 2026-09-29T15:23:01+00:00 yes https://xdme.com/watch-book1-q098.html https://xdme.com/book1-thumbs/page-098.jpg Why Don't the Planets Crash Into Each Other? Space Lanes! Planets share the solar system without traffic jams. They orbit at different distances, like lanes on a highway, and they move at different speeds, with planets closer to the Sun z https://socialmedia.xdme.com/videos/page-098.mp4 https://www.youtube.com/embed/mm5H8cXvz6Y 137 2026-09-29T15:22:58+00:00 yes https://xdme.com/watch-book1-q099.html https://xdme.com/book1-thumbs/page-099.jpg What Is a Black Hole? Without the Scary Movie Version! Forget the scary movies, here is the real science. When a big star uses up its fuel, it collapses under its own gravity, and what is left is tiny and very dark. A black hole forms https://socialmedia.xdme.com/videos/page-099.mp4 https://www.youtube.com/embed/KXm35X3t8u8 128 2026-09-29T15:22:59+00:00 yes https://xdme.com/watch-book1-q100.html https://xdme.com/book1-thumbs/page-100.jpg Why Go to Space at All? Big Reasons, Little Planet! Space exploration can seem far away from daily life, but the page gives three big reasons to go. We learn how Earth and the universe work, we use weather satellites, GPS and scienc https://socialmedia.xdme.com/videos/page-100.mp4 https://www.youtube.com/embed/SEZzOB2DFck 133 2026-09-29T15:23:06+00:00 yes https://xdme.com/watch-book1-q101.html https://xdme.com/book1-thumbs/page-101.jpg Why Does Popcorn Pop? A Tiny Pressure Cooker! Every popcorn kernel is a tiny pressure cooker with water inside. When it is heated, the water turns into steam, and the steam bursts the tough outer shell, called the pericarp, wh https://socialmedia.xdme.com/videos/page-101.mp4 https://www.youtube.com/embed/PA6XhjVtmk8 135 2026-09-29T15:23:04+00:00 yes https://xdme.com/watch-book1-q102.html https://xdme.com/book1-thumbs/page-102.jpg Why Do Airplanes Fly? Lift, Thrust and Smart Wings! Huge airplanes stay in the sky thanks to lift, thrust and smartly shaped wings. As a wing moves forward, its shape turns the air downward, and the air pushes the wing up, which is https://socialmedia.xdme.com/videos/page-102.mp4 https://www.youtube.com/embed/ror0MzN_cmo 126 2026-09-29T15:23:02+00:00 yes https://xdme.com/watch-book1-q103.html https://xdme.com/book1-thumbs/page-103.jpg Why Does Soap Clean Things? Tiny Molecules With Two Ends! Water alone slides right off grease, so how does soap help? A soap molecule has one end that loves water and another that loves grease. The grease-loving tails tuck in around the o https://socialmedia.xdme.com/videos/page-103.mp4 https://www.youtube.com/embed/QoXGC6y48HE 125 2026-09-29T15:23:08+00:00 yes https://xdme.com/watch-book1-q104.html https://xdme.com/book1-thumbs/page-104.jpg Why Do Magnets Stick? North, South and Tiny Iron Bits! Magnets have a north pole and a south pole. Opposite poles pull together and the same poles push apart. Tiny iron bits inside some metals line up and get pulled by a magnet. The pa https://socialmedia.xdme.com/videos/page-104.mp4 https://www.youtube.com/embed/b4Oo5Kz2ncc 132 2026-09-29T15:23:06+00:00 yes https://xdme.com/watch-book1-q105.html https://xdme.com/book1-thumbs/page-105.jpg Why Is a Fridge Cold? It Moves Heat Out! A fridge does not make cold, it moves heat out of the box. A special fluid carries the heat away, and the heat dumps out through the coils at the back so the inside stays cold. Tha https://socialmedia.xdme.com/videos/page-105.mp4 https://www.youtube.com/embed/5rWfGix83q4 124 2026-09-29T15:23:09+00:00 yes https://xdme.com/watch-book1-q106.html https://xdme.com/book1-thumbs/page-106.jpg How Does a Light Bulb Work? Filaments vs. LEDs! In an old-style bulb, electricity flows through a thin part called a filament, and it gets so hot that it glows. LED bulbs glow with tiny chips and give off less heat. The page say https://socialmedia.xdme.com/videos/page-106.mp4 https://www.youtube.com/embed/rLHhrbKRfxk 128 2026-09-29T15:23:10+00:00 yes https://xdme.com/watch-book1-q107.html https://xdme.com/book1-thumbs/page-107.jpg How Does a Touchscreen Know Your Finger? Tap, swipe, zoom, and your screen knows exactly what your finger did. The page explains that the glass holds a faint electric field, your finger changes that field, and the phone m https://socialmedia.xdme.com/videos/page-107.mp4 https://www.youtube.com/embed/QztymnsilcY 128 2026-09-29T15:23:19+00:00 yes https://xdme.com/watch-book1-q108.html https://xdme.com/book1-thumbs/page-108.jpg Why Do Bikes Stay Up? The Science of Balance! Bikes look like they should tip over, but they stay up while you ride. Moving wheels want to keep pointing the same way, and you steer tiny bits without noticing. Speed plus balanc https://socialmedia.xdme.com/videos/page-108.mp4 https://www.youtube.com/embed/K9RkKSh7ABQ 124 2026-09-29T15:23:11+00:00 yes https://xdme.com/watch-book1-q109.html https://xdme.com/book1-thumbs/page-109.jpg Why Do Boats Float? The Secret of Buoyancy! A giant steel ship can float while a small rock sinks, and it is all about pushing water aside. Water pushes up on things, and that push is called buoyancy. A boat pushes a lot of https://socialmedia.xdme.com/videos/page-109.mp4 https://www.youtube.com/embed/E9GJfWefbI0 129 2026-09-29T15:23:12+00:00 yes https://xdme.com/watch-book1-q110.html https://xdme.com/book1-thumbs/page-110.jpg Why Does Rubber Stretch? Tangled Chains That Snap Back! Rubber is made of long, tangled molecule chains. When you pull, the chains unkink and straighten out, and when you let go they snap back into a tangle. The page says pulling too mu https://socialmedia.xdme.com/videos/page-110.mp4 https://www.youtube.com/embed/yqeJsiTqkLM 131 2026-09-29T15:23:13+00:00 yes https://xdme.com/watch-book1-q111.html https://xdme.com/book1-thumbs/page-111.jpg Why Does Metal Rust? Iron, Oxygen and Water! Rust does not happen by magic. Iron meets oxygen and water, and they join to make iron oxide, that flaky orange stuff we call rust. A shiny nail is smooth, shiny and strong, while https://socialmedia.xdme.com/videos/page-111.mp4 https://www.youtube.com/embed/9mTcUuv2_ZE 134 2026-09-29T15:23:15+00:00 yes https://xdme.com/watch-book1-q112.html https://xdme.com/book1-thumbs/page-112.jpg Why Do Echoes Bounce? Sound Bounces Back Late! Shout at a far wall and your voice comes back to you! Sound starts with vibrations and travels through the air in waves, and when a wave hits a hard surface it reflects, bouncing b https://socialmedia.xdme.com/videos/page-112.mp4 https://www.youtube.com/embed/nXmQ14cr_7s 127 2026-09-29T15:23:14+00:00 yes https://xdme.com/watch-book1-q113.html https://xdme.com/book1-thumbs/page-113.jpg How Do Clocks Keep Time? Ticks, Swings and Crystals! A clock counts equal ticks, and that is how it keeps time. Old clocks used swinging pendulums to count, and many clocks now count tiny crystal vibrations. The page says a second is https://socialmedia.xdme.com/videos/page-113.mp4 https://www.youtube.com/embed/tbHexUTRlyI 134 2026-09-29T15:23:16+00:00 yes https://xdme.com/watch-book1-q114.html https://xdme.com/book1-thumbs/page-114.jpg How Does a Toilet Flush? The Science of the Siphon! Ever wondered what happens after you flush? When you lift the flap, water rushes from the tank into the bowl. The fast water carries waste away, and then a siphon pull finishes the https://socialmedia.xdme.com/videos/page-114.mp4 https://www.youtube.com/embed/2HMr_97O3nY 132 2026-09-29T15:23:17+00:00 yes https://xdme.com/watch-book1-q115.html https://xdme.com/book1-thumbs/page-115.jpg How Does a Zipper Work? Teeth, Tape and a Sneaky Slider! A zipper is a clever machine with just a few parts. Each side has a row of teeth, and the slider wedges the teeth together as you pull it up. Pull it the other way and the wedge sp https://socialmedia.xdme.com/videos/page-115.mp4 https://www.youtube.com/embed/dY7RnLb8NwY 122 2026-09-29T15:17:39+00:00 yes https://xdme.com/watch-book1-q116.html https://xdme.com/book1-thumbs/page-116.jpg How Does Velcro Stick? Tiny Hooks and Loops! Velcro sticks using hooks and loops. One side is covered with tiny stiff hooks, and the other side has tiny soft loops, and the hooks catch the loops until you peel them apart. The https://socialmedia.xdme.com/videos/page-116.mp4 https://www.youtube.com/embed/xFtnY1NTdOU 123 2026-09-29T15:17:28+00:00 yes https://xdme.com/watch-book1-q117.html https://xdme.com/book1-thumbs/page-117.jpg Why Do Glasses Help You See? Bending Light Just Right! Glasses help by bending light. Your eyes bend light onto the back of the eye, but some eyes bend it too much or too little, so the picture does not land in the right spot. Lenses a https://socialmedia.xdme.com/videos/page-117.mp4 https://www.youtube.com/embed/dFSV3Aisokc 119 2026-09-29T15:17:37+00:00 yes https://xdme.com/watch-book1-q118.html https://xdme.com/book1-thumbs/page-118.jpg How Do Headphones Make Sound? Shaking Air Into Music! Music from headphones starts as electricity. The music player sends an electrical pattern through the cable that matches the song, and that pattern makes a coil and magnet push and https://socialmedia.xdme.com/videos/page-118.mp4 https://www.youtube.com/embed/P21TQDibPZc 127 2026-09-29T15:17:29+00:00 yes https://xdme.com/watch-book1-q119.html https://xdme.com/book1-thumbs/page-119.jpg How Does Wi-Fi Work? Invisible Radio Waves! Wi-Fi feels like magic, but it is radio. A box called a router sends invisible radio waves, and your device catches them. The waves carry tiny on-off codes that become pictures and https://socialmedia.xdme.com/videos/page-119.mp4 https://www.youtube.com/embed/3vI7kT8N3MQ 124 2026-09-29T15:17:34+00:00 yes https://xdme.com/watch-book1-q120.html https://xdme.com/book1-thumbs/page-120.jpg How Does a Battery Work? Chemical Energy to Electricity! A battery stores chemical energy. Inside, two sides want to react, and that reaction pushes electrons through a wire as electricity, like the wire that lights a bulb in a simple ci https://socialmedia.xdme.com/videos/page-120.mp4 https://www.youtube.com/embed/grFg1dq4MYM 128 2026-09-29T15:17:31+00:00 yes https://xdme.com/watch-book1-q121.html https://xdme.com/book1-thumbs/page-121.jpg Why Do Mirrors Flip Left and Right? Or Do They? Mirrors seem to swap left and right, but the page says that is not quite what happens. A mirror bounces light straight back, so it flips front to back and not really left to right. https://socialmedia.xdme.com/videos/page-121.mp4 https://www.youtube.com/embed/W7humwwcDWk 117 2026-09-29T15:17:32+00:00 yes https://xdme.com/watch-book1-q122.html https://xdme.com/book1-thumbs/page-122.jpg Why Do Balloons Stick to Your Hair? Static Electricity! Rub a balloon on your hair and it clings like magic, but it is really static electricity. Rubbing moves tiny charges, so the hair and the balloon end up with opposite charges. Oppo https://socialmedia.xdme.com/videos/page-122.mp4 https://www.youtube.com/embed/nagedXvJojM 128 2026-09-29T15:17:35+00:00 yes https://xdme.com/watch-book1-q123.html https://xdme.com/book1-thumbs/page-123.jpg Why Does a Straw Work? It's Not Really Sucking! When you drink through a straw, you do not really suck the drink up. You lower the air pressure inside the straw, outside air pushes on the drink, and that push sends the liquid up https://socialmedia.xdme.com/videos/page-123.mp4 https://www.youtube.com/embed/WR0n_YFMU6g 114 2026-09-29T15:17:33+00:00 yes https://xdme.com/watch-book1-q124.html https://xdme.com/book1-thumbs/page-124.jpg Why Do Bubbles Pop? A Thin Skin of Water! A bubble is a thin water skin with air inside. Soap makes that skin stretchy, but when the skin dries or gets poked, the air rushes out and the bubble pops. The page says a bubble https://socialmedia.xdme.com/videos/page-124.mp4 https://www.youtube.com/embed/Eis69302wIg 123 2026-09-29T15:23:21+00:00 yes https://xdme.com/watch-book1-q125.html https://xdme.com/book1-thumbs/page-125.jpg Why Does Glue Stick? A Handshake at the Surface! Glue is a sticky handshake between two surfaces. Wet glue flows into tiny surface pits, grabs both sides like a handshake, and then dries or sets and holds. The page says glue need https://socialmedia.xdme.com/videos/page-125.mp4 https://www.youtube.com/embed/IHhdvMJHS0s 125 2026-09-29T15:23:18+00:00 yes https://xdme.com/watch-book1-q126.html https://xdme.com/book1-thumbs/page-126.jpg Why Does Bread Rise? Meet the Tiny Yeast Helpers! Bread puffs up because of tiny living helpers! Yeast are living microbes that eat sugar and make carbon dioxide gas, and the stretchy dough traps the bubbles so the loaf puffs. The https://socialmedia.xdme.com/videos/page-126.mp4 https://www.youtube.com/embed/ebSuXZECQS8 120 2026-09-29T15:23:23+00:00 yes https://xdme.com/watch-book1-q127.html https://xdme.com/book1-thumbs/page-127.jpg Why Does Ice Float? Water's Roomy Crystals! Most solids sink in their own liquid, but ice floats! When water freezes, it locks into a roomy crystal made of hexagons, and the extra empty space makes ice less dense so it float https://socialmedia.xdme.com/videos/page-127.mp4 https://www.youtube.com/embed/3lzLFIMZFSc 124 2026-09-29T15:17:36+00:00 yes https://xdme.com/watch-book1-q128.html https://xdme.com/book1-thumbs/page-128.jpg Why Do Apples Turn Brown? A Chemical Suntan! Cut an apple and it starts to brown. The cut lets oxygen in, and an enzyme in the apple cells meets natural compounds and browns them. Acids in lemon juice slow the enzyme and help https://socialmedia.xdme.com/videos/page-128.mp4 https://www.youtube.com/embed/06l73ga_-ns 127 2026-09-29T15:17:38+00:00 yes https://xdme.com/watch-book1-q129.html https://xdme.com/book1-thumbs/page-129.jpg Why Does Salt Melt Ice? Getting in the Way of Freezing! Ice and a little water sit together, and adding salt changes things. Salt gets in the way of freezing, so the ice must be colder to stay solid, and it melts. The page says salty sl https://socialmedia.xdme.com/videos/page-129.mp4 https://www.youtube.com/embed/dqjdvtYhAPU 120 2026-09-29T15:23:20+00:00 yes https://xdme.com/watch-book1-q130.html https://xdme.com/book1-thumbs/page-130.jpg Boiling or Simmering? What's the Difference? Boiling and simmering are two different ways to heat water. Heat makes water molecules move faster. Simmer is gentle heat with small bubbles that are steady and calm, while a boil https://socialmedia.xdme.com/videos/page-130.mp4 https://www.youtube.com/embed/TOEh2YIMutA 126 2026-09-29T15:17:40+00:00 yes https://xdme.com/watch-book1-q131.html https://xdme.com/book1-thumbs/page-131.jpg Why Do Eggs Get Hard When Cooked? Proteins on the Move! A runny egg turns firm in the pan, and proteins are the reason. Raw egg proteins are folded chains, heat unfolds them, and then the chains tangle and lock into a firm bite. A raw e https://socialmedia.xdme.com/videos/page-131.mp4 https://www.youtube.com/embed/5lhHzMlqET8 125 2026-09-29T15:23:28+00:00 yes https://xdme.com/watch-book1-q132.html https://xdme.com/book1-thumbs/page-132.jpg Why Does Chocolate Melt in Your Hand? Cocoa Butter Science! Chocolate is full of special fats, and those fats melt near body heat. Your hand is about 37 degrees C, which is warm enough to turn solid chocolate soft, smooth and eventually liq https://socialmedia.xdme.com/videos/page-132.mp4 https://www.youtube.com/embed/hDet81iPT6g 124 2026-09-29T15:17:41+00:00 yes https://xdme.com/watch-book1-q133.html https://xdme.com/book1-thumbs/page-133.jpg Yeast or Baking Powder? What Makes Dough Rise? Yeast and baking powder both help dough rise, but in different ways. Yeast is alive and slow, while baking powder is a chemical mix, and both make bubbles that lift the dough. The https://socialmedia.xdme.com/videos/page-133.mp4 https://www.youtube.com/embed/38dcWfugNyU 132 2026-09-29T15:23:24+00:00 yes https://xdme.com/watch-book1-q134.html https://xdme.com/book1-thumbs/page-134.jpg Why Does Spicy Food Feel Hot? Meet Capsaicin! Spicy food feels hot even though there is no fire! Chili has a chemical called capsaicin, which tickles heat sensors on your tongue, and your brain reads that spice as heat. The pa https://socialmedia.xdme.com/videos/page-134.mp4 https://www.youtube.com/embed/SuNLATkvpN4 132 2026-09-29T15:23:25+00:00 yes https://xdme.com/watch-book1-q135.html https://xdme.com/book1-thumbs/page-135.jpg Why Do Leftovers Go Bad? Meet the Tiny Microbes! Leftovers can go bad because tiny microbes love them too. Bacteria and mold are everywhere and eat the same food we do, and warm, wet food helps them multiply fast. Cold slows them https://socialmedia.xdme.com/videos/page-135.mp4 https://www.youtube.com/embed/GMU9VOQwoGA 124 2026-09-29T15:23:26+00:00 yes https://xdme.com/watch-book1-q136.html https://xdme.com/book1-thumbs/page-136.jpg Why Does a Metal Spoon Get Hot? Heat on the Move! Stir hot soup with a metal spoon and the handle soon feels warm. Heat is moving energy, and metal atoms pass that energy along fast, so the handle warms up after the bowl of the sp https://socialmedia.xdme.com/videos/page-136.mp4 https://www.youtube.com/embed/TgIfAgSkTgU 128 2026-09-29T15:23:27+00:00 yes https://xdme.com/watch-book1-q137.html https://xdme.com/book1-thumbs/page-137.jpg Why Do Cold Glasses Get Wet? The Water Comes From the Air! Where does the water on a cold glass come from? Air holds invisible water vapor, and a cold glass cools the air right beside it. That vapor turns into droplets, which is called con https://socialmedia.xdme.com/videos/page-137.mp4 https://www.youtube.com/embed/stJMR8F6aHA 122 2026-09-29T15:23:30+00:00 yes https://xdme.com/watch-book1-q138.html https://xdme.com/book1-thumbs/page-138.jpg Microwave or Oven? How Do They Heat Food Differently? Microwaves and ovens both heat food, but in different ways. An oven heats the air around the food, while a microwave wiggles water molecules inside it. That is why leftovers heat f https://socialmedia.xdme.com/videos/page-138.mp4 https://www.youtube.com/embed/GXlq2BAmQBo 134 2026-09-29T15:23:32+00:00 yes https://xdme.com/watch-book1-q139.html https://xdme.com/book1-thumbs/page-139.jpg Why Does Toast Turn Brown? The Maillard Reaction! Toasting bread changes more than its color. Heat changes the sugars and proteins in bread, and that browning is called a Maillard reaction. Toast for too long and the brown becomes https://socialmedia.xdme.com/videos/page-139.mp4 https://www.youtube.com/embed/YFUuRp-JSCY 126 2026-09-29T15:23:31+00:00 yes https://xdme.com/watch-book1-q140.html https://xdme.com/book1-thumbs/page-140.jpg Why Does Water Boil at 100°C? Molecules Break Free! Heat makes water molecules fly apart. At 100 degrees C they have enough energy to become steam. The page says high mountains boil a bit cooler because air presses less, and salt wa https://socialmedia.xdme.com/videos/page-140.mp4 https://www.youtube.com/embed/EfvliSXB9BU 131 2026-09-29T15:17:42+00:00 yes https://xdme.com/watch-book1-q141.html https://xdme.com/book1-thumbs/page-141.jpg Why Does Sugar Dissolve? Water Molecules Pull It Apart! Stir sugar into water and it seems to vanish. Water molecules surround the sugar and pull its crystals apart, and stirring and heat help the pull go faster. The page says there is https://socialmedia.xdme.com/videos/page-141.mp4 https://www.youtube.com/embed/36BiZYmSc6E 128 2026-09-29T15:23:42+00:00 yes https://xdme.com/watch-book1-q142.html https://xdme.com/book1-thumbs/page-142.jpg Why Does Milk Go Sour? Tiny Microbes Make Acid! Milk goes sour because of tiny living things. Milk has sugars that microbes can eat, and those microbes make acid, and acid makes milk taste sour and get lumpy. The page compares f https://socialmedia.xdme.com/videos/page-142.mp4 https://www.youtube.com/embed/SlN6mZ4Eefw 122 2026-09-29T15:23:33+00:00 yes https://xdme.com/watch-book1-q143.html https://xdme.com/book1-thumbs/page-143.jpg Why Does Oil Float on Water? Density in a Jar! Oil and water do not mix well, and oil floats on top. The page explains that oil is less dense, so it rides on top of the water, which is more dense. Soap can help them join for wa https://socialmedia.xdme.com/videos/page-143.mp4 https://www.youtube.com/embed/D20RZwQatDU 119 2026-09-29T15:23:35+00:00 yes https://xdme.com/watch-book1-q144.html https://xdme.com/book1-thumbs/page-144.jpg Why Do Cookies Spread in the Oven? Butter, Bubbles and Heat! Ever wondered why a round ball of dough turns into a flat cookie? In the oven, butter melts and the dough loosens, bubbles puff the cookie, and then heat sets the edges. The page s https://socialmedia.xdme.com/videos/page-144.mp4 https://www.youtube.com/embed/1dhGkRZP3hA 120 2026-09-29T15:23:44+00:00 yes https://xdme.com/watch-book1-q145.html https://xdme.com/book1-thumbs/page-145.jpg Why Does Pasta Get Soft? Starch Swells in Hot Water! Dry pasta is packed starch, which is why it is firm, stiff and stays straight. Hot water soaks in, the starch swells and the noodle turns tender, flexible and soft. The page says e https://socialmedia.xdme.com/videos/page-145.mp4 https://www.youtube.com/embed/0lE0YRcUOhU 125 2026-09-29T15:23:37+00:00 yes https://xdme.com/watch-book1-q146.html https://xdme.com/book1-thumbs/page-146.jpg Why Does Baking Soda Fizz? A Base Meets an Acid! Fizz! Baking soda is a base and vinegar is an acid, and when they meet they make carbon dioxide bubbles, shown as CO2 on the page. The page says the fizz is a gas you already breat https://socialmedia.xdme.com/videos/page-146.mp4 https://www.youtube.com/embed/5UymdTV8y9c 126 2026-09-29T15:23:36+00:00 yes https://xdme.com/watch-book1-q147.html https://xdme.com/book1-thumbs/page-147.jpg Why Does Ice Cream Melt? Frozen Water, Fat and Air! Ice cream is frozen water, fat and air, and room heat gives its molecules energy. The solid mix turns slushy and then into soup. The page says freezer cold locks the mix in place. https://socialmedia.xdme.com/videos/page-147.mp4 https://www.youtube.com/embed/WkE0ybxEFjQ 129 2026-09-29T15:23:39+00:00 yes https://xdme.com/watch-book1-q148.html https://xdme.com/book1-thumbs/page-148.jpg Why Does Honey Last So Long? A Sticky Science Secret! Honey can last for years, and the page gives three clues. Honey is very low in water, it is also acidic with a pH of about 3.9, and most microbes cannot grow in it. The page says s https://socialmedia.xdme.com/videos/page-148.mp4 https://www.youtube.com/embed/_OlPBsZ5tbk 126 2026-09-29T15:23:38+00:00 yes https://xdme.com/watch-book1-q149.html https://xdme.com/book1-thumbs/page-149.jpg Why Does Steam Burn More Than Water? Hidden Heat! Steam can burn you even more than hot water can. Steam is water as a gas, and it carries extra hidden heat. When it hits skin it turns back into water and dumps that heat. The page https://socialmedia.xdme.com/videos/page-149.mp4 https://www.youtube.com/embed/qxULiy1DXY4 128 2026-09-29T15:23:43+00:00 yes https://xdme.com/watch-book1-q150.html https://xdme.com/book1-thumbs/page-150.jpg Why Do We Cook Food at All? Three Big Reasons! Why do we cook food at all? The page gives three reasons. Heat can kill harmful microbes, which makes food safer, and it makes some foods easier to chew and digest so our bodies ca https://socialmedia.xdme.com/videos/page-150.mp4 https://www.youtube.com/embed/rWeF3saLLqM 125 2026-09-29T15:23:41+00:00 yes https://xdme.com/watch-book2-q001.html https://xdme.com/book2-thumbs/page-001.jpg Why Do We Forget Why We Walked In? Have you ever walked into a room and thought, wait, why did I come in here? Your brain makes a plan in one room. Then a doorway can reset that plan! https://socialmedia.xdme.com/tony/videos-book2-real/page-001.mp4 https://www.youtube.com/embed/fZqojCZKsaI 124 2026-09-30T07:16:06+00:00 yes https://xdme.com/watch-book2-q002.html https://xdme.com/book2-thumbs/page-002.jpg Why Do We Dream? Did you ever wake up from a dream about a castle in the clouds? Your brain is busy at night. Sleep is when the brain sorts the day. https://socialmedia.xdme.com/tony/videos-book2-real/page-002.mp4 https://www.youtube.com/embed/DX82B97TsKM 135 2026-09-30T07:16:07+00:00 yes https://xdme.com/watch-book2-q003.html https://xdme.com/book2-thumbs/page-003.jpg Why Can't We Tickle Ourselves? Have you ever tried to tickle yourself? It just does not work! Tickles need surprise, and your brain predicts your own touch. Scientists have even fooled the brain with a robot arm https://socialmedia.xdme.com/tony/videos-book2-real/page-003.mp4 https://www.youtube.com/embed/IJrrRe0Ow0A 129 2026-09-30T07:42:20+00:00 yes https://xdme.com/watch-book2-q004.html https://xdme.com/book2-thumbs/page-004.jpg Why Do We Get Brain Freeze? Have you ever gulped a frozen treat, and then, ouch, your forehead hurts? That is brain freeze! Ice-cold food on the roof of your mouth can make your forehead hurt. https://socialmedia.xdme.com/tony/videos-book2-real/page-004.mp4 https://www.youtube.com/embed/iK9oydl4gvY 132 2026-09-30T07:25:12+00:00 yes https://xdme.com/watch-book2-q005.html https://xdme.com/book2-thumbs/page-005.jpg Why Do We Yawn When Someone Else Yawns? Whoa, did you just want to yawn? Yawns can be catching! Seeing a yawn can start your own yawn, even if you are not sleepy. Yawns can spread through a whole group of people. https://socialmedia.xdme.com/tony/videos-book2-real/page-005.mp4 https://www.youtube.com/embed/LiMoQvm_9Gs 130 2026-09-30T08:49:40+00:00 yes https://xdme.com/watch-book2-q006.html https://xdme.com/book2-thumbs/page-006.jpg Why Do Songs Get Stuck in Our Head? Have you ever had a song play again and again in your head, even when you wanted it to stop? That's an earworm! Short, loop-y bits of music are easy for your brain to replay. https://socialmedia.xdme.com/tony/videos-book2-real/page-006.mp4 https://www.youtube.com/embed/ohI3yQx2Ut4 124 2026-09-30T08:10:29+00:00 yes https://xdme.com/watch-book2-q007.html https://xdme.com/book2-thumbs/page-007.jpg Why Do We Talk in Our Sleep? Has anyone ever told you that you said something funny in your sleep? Sleep talking is a short mix-up. While you are sleeping, one little part of the brain gets busy, and words sli https://socialmedia.xdme.com/tony/videos-book2-real/page-007.mp4 https://www.youtube.com/embed/ZH2aHHZYZIg 122 2026-09-30T09:46:31+00:00 yes https://xdme.com/watch-book2-q008.html https://xdme.com/book2-thumbs/page-008.jpg Why Does Practice Make Us Better? Have you ever tried something new that felt really hard, and then got easier with practice? Paths get faster! Each repeat wears a smoother trail in your brain. https://socialmedia.xdme.com/tony/videos-book2-real/page-008.mp4 https://www.youtube.com/embed/8svwfks4roE 121 2026-09-30T09:00:15+00:00 yes https://xdme.com/watch-book2-q009.html https://xdme.com/book2-thumbs/page-009.jpg Why Do We Have Two Sides of the Brain? Did you know your brain has two halves, like a walnut split down the middle? They are a team! Two hemispheres share the work. Both sides work on almost everything you do. https://socialmedia.xdme.com/tony/videos-book2-real/page-009.mp4 https://www.youtube.com/embed/oxtdO8eA0hs 120 2026-09-30T10:09:44+00:00 yes https://xdme.com/watch-book2-q010.html https://xdme.com/book2-thumbs/page-010.jpg Why Does the Brain Use So Much Energy? Your brain is small, but it is one hungry organ! Even though it is small, it uses a big share of your body's energy, because being ready to fire is expensive. Let's find out just h https://socialmedia.xdme.com/tony/videos-book2-real/page-010.mp4 https://www.youtube.com/embed/OcWYKdr7xA0 116 2026-09-30T10:39:06+00:00 yes https://xdme.com/watch-book2-q011.html https://xdme.com/book2-thumbs/page-011.jpg Why Do We Get Dizzy When We Spin? Have you ever spun around and around, and then the whole world kept spinning? That is because fluid in your inner ear keeps moving even after you stop. Let's see how your ears and https://socialmedia.xdme.com/tony/videos-book2-real/page-011.mp4 https://www.youtube.com/embed/H1SVx7aBQqY 118 2026-09-30T10:20:19+00:00 yes https://xdme.com/watch-book2-q012.html https://xdme.com/book2-thumbs/page-012.jpg Why Do Smells Bring Back Memories? Have you ever smelled something and suddenly remembered a special place or time? Smell lives next to memory! The paths for smell sit close to the parts of the brain for memory and https://socialmedia.xdme.com/tony/videos-book2-real/page-012.mp4 https://www.youtube.com/embed/lo4vSlDymTc 120 2026-09-30T10:58:25+00:00 yes https://xdme.com/watch-book2-q013.html https://xdme.com/book2-thumbs/page-013.jpg Why Do We Talk to Ourselves? Have you ever caught yourself talking out loud when you are alone? Good news, it is normal! Inner talk is a tool. Saying it out loud can make a tricky step clearer. https://socialmedia.xdme.com/tony/videos-book2-real/page-013.mp4 https://www.youtube.com/embed/yUpaS_TmtfM 117 2026-09-30T10:48:21+00:00 yes https://xdme.com/watch-book2-q014.html https://xdme.com/book2-thumbs/page-014.jpg Why Does the Mind Go Blank on a Test? Have you ever known an answer at home, and then forgotten it during a test? You are not alone, and it does not mean you did not learn it. The answer can be in there, but stress can https://socialmedia.xdme.com/tony/videos-book2-real/page-014.mp4 https://www.youtube.com/embed/eDMS8NSsXKY 111 2026-09-30T11:07:29+00:00 yes https://xdme.com/watch-book2-q015.html https://xdme.com/book2-thumbs/page-015.jpg Why Are Some People Left-Handed? Do you write with your left hand, or do you know someone who does? About 1 in 10 kids lead with the left. That means their brain chose the left side to be in charge of many actions https://socialmedia.xdme.com/tony/videos-book2-real/page-015.mp4 https://www.youtube.com/embed/jGWtmI9JKBQ 125 2026-09-30T11:20:04+00:00 yes https://xdme.com/watch-book2-q016.html https://xdme.com/book2-thumbs/page-016.jpg Why Do We Jerk Awake When We Fall Asleep? Have you ever been drifting off, and then your whole body suddenly jumped? That is a sleep switch glitch. Scientists call it a hypnic jerk. https://socialmedia.xdme.com/tony/videos-book2-real/page-016.mp4 https://www.youtube.com/embed/OpXZa2vRokk 117 2026-09-30T11:30:37+00:00 yes https://xdme.com/watch-book2-q017.html https://xdme.com/book2-thumbs/page-017.jpg Why Can't We Remember Being a Baby? Can you remember being a baby? Most people cannot! That is because baby brains are still building the memory system. This is called childhood amnesia. https://socialmedia.xdme.com/tony/videos-book2-real/page-017.mp4 https://www.youtube.com/embed/bf6hcUq-FhA 125 2026-09-30T11:37:10+00:00 yes https://xdme.com/watch-book2-q018.html https://xdme.com/book2-thumbs/page-018.jpg Why Do We See Faces in Clouds? Have you ever looked up and seen a smiling face in a cloud? The brain is a face-finder! It would rather guess face than miss a real one. https://socialmedia.xdme.com/tony/videos-book2-real/page-018.mp4 https://www.youtube.com/embed/Bj9Es9FloeQ 117 2026-09-30T11:43:13+00:00 yes https://xdme.com/watch-book2-q019.html https://xdme.com/book2-thumbs/page-019.jpg Why Do Sudden Sounds Make Us Jump? Have you ever jumped when a door slammed nearby? The alarm path is faster than thinking! The body can move before the thinking part finishes. https://socialmedia.xdme.com/tony/videos-book2-real/page-019.mp4 https://www.youtube.com/embed/N8jZhqiy5ck 115 2026-09-30T11:52:48+00:00 yes https://xdme.com/watch-book2-q020.html https://xdme.com/book2-thumbs/page-020.jpg Why Does Music Give Some People Chills? Has a song ever made your arms tingle or your skin get goosebumps? Those are music chills. When music hits a surprise the brain likes, reward chemicals can tingle the skin. https://socialmedia.xdme.com/tony/videos-book2-real/page-020.mp4 https://www.youtube.com/embed/tgwtNMcGK_U 121 2026-09-30T11:59:50+00:00 yes https://xdme.com/watch-book2-q021.html https://xdme.com/book2-thumbs/page-021.jpg Why Do We Get Deja Vu? Have you ever felt that you had already lived a moment that you knew was brand new? That feeling is called deja vu. It is a brief mix-up, where the brain tags a moment as familiar https://socialmedia.xdme.com/tony/videos-book2-real/page-021.mp4 https://www.youtube.com/embed/tcQV3dJwtZ4 117 2026-09-30T12:09:25+00:00 yes https://xdme.com/watch-book2-q022.html https://xdme.com/book2-thumbs/page-022.jpg Why Do We Count Without Thinking? Can you tell there are three cookies on a plate without counting? You can, because the brain tracks small amounts automatically. Number sense starts early, even in babies! https://socialmedia.xdme.com/tony/videos-book2-real/page-022.mp4 https://www.youtube.com/embed/bgHhqVS42gM 123 2026-09-30T12:16:58+00:00 yes https://xdme.com/watch-book2-q023.html https://xdme.com/book2-thumbs/page-023.jpg Why Does Chewing Help Some People Think? Have you ever noticed that some people chew gum when they study? A little attention wake-up! Steady chewing can wake attention a little. https://socialmedia.xdme.com/tony/videos-book2-real/page-023.mp4 https://www.youtube.com/embed/-L6QCm54kO8 122 2026-09-30T12:44:42+00:00 yes https://xdme.com/watch-book2-q024.html https://xdme.com/book2-thumbs/page-024.jpg Why Do We Remember the First and Last Things on a List? Have you ever learned a shopping list, and remembered the first and last items best? That happens because the start is fresh, and the end is recent. And the middle has to fight bot https://socialmedia.xdme.com/tony/videos-book2-real/page-024.mp4 https://www.youtube.com/embed/3ILaBEk24W8 123 2026-09-30T12:19:59+00:00 yes https://xdme.com/watch-book2-q025.html https://xdme.com/book2-thumbs/page-025.jpg Why Does Sleep Help Us Remember? Did you ever learn something new, sleep on it, and remember it better the next day? Sleep files the day! Without sleep, new paths in the brain stay messy. https://socialmedia.xdme.com/tony/videos-book2-real/page-025.mp4 https://www.youtube.com/embed/Uw28gZcfvO8 121 2026-09-30T12:51:45+00:00 yes https://xdme.com/watch-book2-q026.html https://xdme.com/book2-thumbs/page-026.jpg Why Do We Blush? Have you ever felt your cheeks get warm and pink? That is blushing! Blood rushes to the face, because embarrassment opens tiny blood vessels there. https://socialmedia.xdme.com/tony/videos-book2-real/page-026.mp4 https://www.youtube.com/embed/imS3cfxlR5U 116 2026-09-30T12:24:01+00:00 yes https://xdme.com/watch-book2-q027.html https://xdme.com/book2-thumbs/page-027.jpg Why Do We Cry When We Are Sad? Sometimes when we feel sad, tears fall down our cheeks. Tears are a signal and a reset. Sad tears can tell other people you need care. https://socialmedia.xdme.com/tony/videos-book2-real/page-027.mp4 https://www.youtube.com/embed/LM2BBVZrJc8 116 2026-09-30T12:57:47+00:00 yes https://xdme.com/watch-book2-q028.html https://xdme.com/book2-thumbs/page-028.jpg Why Do We Cry When We Are Happy? Have you ever been so happy that tears came to your eyes? Big feelings share one tap! Joy can be so big that the same tear system turns on. https://socialmedia.xdme.com/tony/videos-book2-real/page-028.mp4 https://www.youtube.com/embed/IrYsmFMnBNA 121 2026-09-30T12:27:02+00:00 yes https://xdme.com/watch-book2-q029.html https://xdme.com/book2-thumbs/page-029.jpg Why Do We Get Butterflies in the Stomach? Have you ever felt fluttery in your tummy before a game or a big test? Gut and brain are talking! Nerves change how the stomach feels. https://socialmedia.xdme.com/tony/videos-book2-real/page-029.mp4 https://www.youtube.com/embed/pM8ttpYAe4Y 122 2026-09-30T13:00:53+00:00 yes https://xdme.com/watch-book2-q030.html https://xdme.com/book2-thumbs/page-030.jpg Why Do We Laugh? Ha ha! What makes you laugh the hardest? A joke, a tickle, or relief can pop the laugh switch. Laughing with someone bonds you faster than laughing alone. https://socialmedia.xdme.com/tony/videos-book2-real/page-030.mp4 https://www.youtube.com/embed/35SRaHAaG-Q 122 2026-09-30T12:30:04+00:00 yes https://xdme.com/watch-book2-q031.html https://xdme.com/book2-thumbs/page-031.jpg Why Do We Get Angry? Have you ever felt hot and grumpy because something was not fair? That is anger! Anger is a warning light. Anger is a feeling. Hurting people is a choice. https://socialmedia.xdme.com/tony/videos-book2-real/page-031.mp4 https://www.youtube.com/embed/FJuGXuH2abc 120 2026-09-30T13:06:55+00:00 yes https://xdme.com/watch-book2-q032.html https://xdme.com/book2-thumbs/page-032.jpg Why Do We Feel Scared? Have you ever jumped when a door slammed, or felt your heart race in the dark? That is fear! Fear is a body alarm, and it helps to keep you safe. https://socialmedia.xdme.com/tony/videos-book2-real/page-032.mp4 https://www.youtube.com/embed/8XvWRYK7-XY 119 2026-09-30T12:34:07+00:00 yes https://xdme.com/watch-book2-q033.html https://xdme.com/book2-thumbs/page-033.jpg Why Do We Feel Jealous? Have you ever felt a tight feeling when a friend got something you wanted? That is jealousy! Jealousy notices a want. Jealousy is very common. https://socialmedia.xdme.com/tony/videos-book2-real/page-033.mp4 https://www.youtube.com/embed/hh2u47fQ2HA 119 2026-09-30T13:09:57+00:00 yes https://xdme.com/watch-book2-q034.html https://xdme.com/book2-thumbs/page-034.jpg Why Do Hugs Help? Have you ever felt better after a good hug? Safe touch can calm the body. A hug can tell your body that you are safe. Only hugs you want are good hugs. https://socialmedia.xdme.com/tony/videos-book2-real/page-034.mp4 https://www.youtube.com/embed/1Mwk4TBvkYY 118 2026-09-30T12:37:39+00:00 yes https://xdme.com/watch-book2-q035.html https://xdme.com/book2-thumbs/page-035.jpg Why Do We Feel Lonely? Have you ever felt alone, even when people were nearby? That is loneliness! The brain looks for belonging, and loneliness is a signal to reconnect. https://socialmedia.xdme.com/tony/videos-book2-real/page-035.mp4 https://www.youtube.com/embed/K1CnKiotGJ4 117 2026-09-30T13:15:29+00:00 yes https://xdme.com/watch-book2-q036.html https://xdme.com/book2-thumbs/page-036.jpg Why Does Worry Feel Like a Tight Chest? Have you ever felt a tight squeeze in your chest when you were worried? Worry tenses the body! A what-if thought can keep your alarm switched on. https://socialmedia.xdme.com/tony/videos-book2-real/page-036.mp4 https://www.youtube.com/embed/iq848MZ0Y8s 119 2026-09-30T12:40:10+00:00 yes https://xdme.com/watch-book2-q037.html https://xdme.com/book2-thumbs/page-037.jpg Why Do We Giggle When We Are Nervous? Have you ever giggled at a time when nothing was funny? That is a mixed signal leak! Nerves can make a giggle slip out. A nervous giggle does not mean you think something is funny. https://socialmedia.xdme.com/tony/videos-book2-real/page-037.mp4 https://www.youtube.com/embed/KRj_3f1ooC8 121 2026-09-30T13:20:45+00:00 yes https://xdme.com/watch-book2-q038.html https://xdme.com/book2-thumbs/page-038.jpg Why Do We Hide Our Face When We Are Embarrassed? Have you ever covered your face when something embarrassing happened? That is a tiny hide reflex! Embarrassment can make your hands fly up to your face. https://socialmedia.xdme.com/tony/videos-book2-real/page-038.mp4 https://www.youtube.com/embed/tu-fDnBXUx4 116 2026-09-30T12:49:14+00:00 yes https://xdme.com/watch-book2-q039.html https://xdme.com/book2-thumbs/page-039.jpg Why Does Kindness Feel Good? When you help someone, your brain lights up a little reward spark. Brains like connecting with other people, and they like caring, too. That spark is why a kind act can feel so goo https://socialmedia.xdme.com/tony/videos-book2-real/page-039.mp4 https://www.youtube.com/embed/MqeC6RT69NY 136 2026-09-30T07:16:10+00:00 yes https://xdme.com/watch-book2-q040.html https://xdme.com/book2-thumbs/page-040.jpg Why Do We Copy Other People's Moods? Feelings can spread from person to person, almost like weather. Your brain watches other people's faces and voices. And it can borrow a little of their mood without you even trying https://socialmedia.xdme.com/tony/videos-book2-real/page-040.mp4 https://www.youtube.com/embed/DuxR0DXTc2k 132 2026-09-30T07:19:40+00:00 yes https://xdme.com/watch-book2-q041.html https://xdme.com/book2-thumbs/page-041.jpg Why Do We Feel Brave After a Hard Thing? When you finish something hard, your brain updates what it thinks you can do. It learns, I did that, so maybe I can do more. That new confidence is a big part of feeling brave afte https://socialmedia.xdme.com/tony/videos-book2-real/page-041.mp4 https://www.youtube.com/embed/vsGRaJmr9no 122 2026-09-30T07:27:43+00:00 yes https://xdme.com/watch-book2-q042.html https://xdme.com/book2-thumbs/page-042.jpg Why Do We Need Friends? Human brains are built to be part of a group, like a pack. Friends share play, they help each other, and they help each other feel calm. That is why friends matter so much. https://socialmedia.xdme.com/tony/videos-book2-real/page-042.mp4 https://www.youtube.com/embed/0Ml8uwL9aP0 127 2026-09-30T08:04:20+00:00 yes https://xdme.com/watch-book2-q043.html https://xdme.com/book2-thumbs/page-043.jpg Why Does Music Change Our Mood? Music is sound, and sound can poke the part of your brain that handles feelings. The beat, the pitch, and your own memories can all change how you feel. So a song can lift you up o https://socialmedia.xdme.com/tony/videos-book2-real/page-043.mp4 https://www.youtube.com/embed/VQIkERBIKqc 130 2026-09-30T08:53:12+00:00 yes https://xdme.com/watch-book2-q044.html https://xdme.com/book2-thumbs/page-044.jpg Why Do We Feel Bored? Boredom is your brain saying, I want something new to work on. It is a nudge to find something worth doing. So boredom is not bad, it is a signal. https://socialmedia.xdme.com/tony/videos-book2-real/page-044.mp4 https://www.youtube.com/embed/NoPhsT2A1TY 124 2026-09-30T09:56:02+00:00 yes https://xdme.com/watch-book2-q045.html https://xdme.com/book2-thumbs/page-045.jpg Why Do We Feel Proud? Pride is the feeling of, I did that! Your brain marks a job you worked hard to earn. That mark makes the good feeling last. Proud of effort lasts longer than proud of luck. https://socialmedia.xdme.com/tony/videos-book2-real/page-045.mp4 https://www.youtube.com/embed/thwKBRHAZl4 128 2026-09-30T10:32:32+00:00 yes https://xdme.com/watch-book2-q046.html https://xdme.com/book2-thumbs/page-046.jpg Why Do We Get Stage Fright? Stage fright happens when your brain turns its alarm up. Being watched can feel like danger, even when you are safe. The good news is that you can turn the alarm down. https://socialmedia.xdme.com/tony/videos-book2-real/page-046.mp4 https://www.youtube.com/embed/wMyo5VJhCmo 126 2026-09-30T10:43:50+00:00 yes https://xdme.com/watch-book2-q047.html https://xdme.com/book2-thumbs/page-047.jpg Why Do We Miss People? Missing someone is a sign that a bond is working. Your brain keeps a kind of map of the people you love. So when someone important is away, the map still points right to them. https://socialmedia.xdme.com/tony/videos-book2-real/page-047.mp4 https://www.youtube.com/embed/16uba656Mqs 132 2026-09-30T10:58:56+00:00 yes https://xdme.com/watch-book2-q048.html https://xdme.com/book2-thumbs/page-048.jpg Why Do We Feel Calm in Nature? Nature is calming because it gives your brain an easier job. Trees, water, and sky are gentle to look at and listen to. So your brain can turn its alarm down, and you feel more rel https://socialmedia.xdme.com/tony/videos-book2-real/page-048.mp4 https://www.youtube.com/embed/6prIG0CiCbo 130 2026-09-30T11:11:01+00:00 yes https://xdme.com/watch-book2-q049.html https://xdme.com/book2-thumbs/page-049.jpg Why Do We Sometimes Yawn When We Are Stressed? Sometimes we yawn when we are stressed, and not only when we are sleepy. A yawn may be a big reset breath when the body is wound up. Scientists are still studying exactly why it ha https://socialmedia.xdme.com/tony/videos-book2-real/page-049.mp4 https://www.youtube.com/embed/csTMkNNIycE 136 2026-09-30T11:23:35+00:00 yes https://xdme.com/watch-book2-q050.html https://xdme.com/book2-thumbs/page-050.jpg Why Do Feelings Show on Our Face? Your face is like a billboard for your feelings. Tiny face muscles move to show what you feel inside. And other people can read the message, often without a single word. https://socialmedia.xdme.com/tony/videos-book2-real/page-050.mp4 https://www.youtube.com/embed/jACYnEN25v8 133 2026-09-30T11:33:39+00:00 yes https://xdme.com/watch-book2-q051.html https://xdme.com/book2-thumbs/page-051.jpg Why Do Onions Make Us Cry? When you cut an onion, it releases a tiny gas that floats up into the air. The gas pokes your eyes, and your eyes try to protect themselves. That is why tears start to flow. https://socialmedia.xdme.com/tony/videos-book2-real/page-051.mp4 https://www.youtube.com/embed/yfrRX7Sr1Jw 129 2026-09-30T11:44:14+00:00 yes https://xdme.com/watch-book2-q052.html https://xdme.com/book2-thumbs/page-052.jpg Why Does Food Taste Dull When We Have a Cold? When you have a cold, food can taste dull, like the flavor got turned down. That is because your stuffy nose blocks the smells that travel to your smell sensors. Your tongue still https://socialmedia.xdme.com/tony/videos-book2-real/page-052.mp4 https://www.youtube.com/embed/xy2SY4FDvtI 130 2026-09-30T21:28:14+00:00 yes https://xdme.com/watch-book2-q053.html https://xdme.com/book2-thumbs/page-053.jpg Why Do We See in Color? Color is how your brain reads the different kinds of light. Special cells in the back of your eye catch the light and read it as color. Then your brain puts all the signals togethe https://socialmedia.xdme.com/tony/videos-book2-real/page-053.mp4 https://www.youtube.com/embed/5Q3eafKnZi4 135 2026-09-30T12:05:23+00:00 yes https://xdme.com/watch-book2-q054.html https://xdme.com/book2-thumbs/page-054.jpg Why Do Our Ears Pop? Your ears pop when the air pressure inside and outside your ear gets out of balance. When it opens, the air moves and, pop, your ears feel normal again. It is a clever little syste https://socialmedia.xdme.com/tony/videos-book2-real/page-054.mp4 https://www.youtube.com/embed/7qjR-x5cNgU 132 2026-09-30T21:33:26+00:00 yes https://xdme.com/watch-book2-q055.html https://xdme.com/book2-thumbs/page-055.jpg Why Does Mint Feel Cold? Why does mint feel cold when nothing got cooler? Mint turns on the cold sensors in your mouth, so your brain thinks it is chilly. It is a playful mix-up between chemistry and feeli https://socialmedia.xdme.com/tony/videos-book2-real/page-055.mp4 https://www.youtube.com/embed/dOqrS1C--ds 133 2026-09-30T12:22:00+00:00 yes https://xdme.com/watch-book2-q056.html https://xdme.com/book2-thumbs/page-056.jpg Why Do We Get Used to a Smell? When you first smell something, your nose shouts about it. But after a while, your brain turns the volume down. That is why you stop noticing a smell that stays around. https://socialmedia.xdme.com/tony/videos-book2-real/page-056.mp4 https://www.youtube.com/embed/30MGkLY6wgE 131 2026-09-30T21:39:58+00:00 yes https://xdme.com/watch-book2-q057.html https://xdme.com/book2-thumbs/page-057.jpg Why Does Spicy Food Feel Like Fire? Why does spicy food feel like fire in your mouth? Spicy food turns on the same sensors that notice real heat, so your brain thinks your mouth is on fire, even though it is not. It https://socialmedia.xdme.com/tony/videos-book2-real/page-057.mp4 https://www.youtube.com/embed/9q9M79-FU_Q 137 2026-09-30T12:32:05+00:00 yes https://xdme.com/watch-book2-q058.html https://xdme.com/book2-thumbs/page-058.jpg Why Do We Sneeze? A sneeze is a fast blast that clears your nose. Dust or a tickle can trigger the sneeze reflex. A reflex is something your body does all by itself, without thinking. https://socialmedia.xdme.com/tony/videos-book2-real/page-058.mp4 https://www.youtube.com/embed/OaqT83HJHd8 123 2026-09-30T21:44:29+00:00 yes https://xdme.com/watch-book2-q059.html https://xdme.com/book2-thumbs/page-059.jpg Why Do We Blink? Blinking is like a tiny windshield wiper for your eyes. Each blink spreads tears across the surface and sweeps away dust. That keeps your eyes wet, clean, and clear. https://socialmedia.xdme.com/tony/videos-book2-real/page-059.mp4 https://www.youtube.com/embed/5rxQ5Zx0XZM 129 2026-09-30T12:37:08+00:00 yes https://xdme.com/watch-book2-q060.html https://xdme.com/book2-thumbs/page-060.jpg Why Do We Have Two Eyes? Each of your eyes sees a slightly different picture. Your brain puts the two pictures together. That gives you a feeling of depth, so you can tell how far away things are. https://socialmedia.xdme.com/tony/videos-book2-real/page-060.mp4 https://www.youtube.com/embed/QPMVoUail6w 133 2026-09-30T21:48:30+00:00 yes https://xdme.com/watch-book2-q061.html https://xdme.com/book2-thumbs/page-061.jpg Why Do We Have Two Ears? Having two ears helps you find where a sound is coming from. A sound usually hits one ear a tiny bit sooner than the other. Your brain uses that little difference to work out the d https://socialmedia.xdme.com/tony/videos-book2-real/page-061.mp4 https://www.youtube.com/embed/XHqBk8YE2CQ 136 2026-09-30T21:28:15+00:00 yes https://xdme.com/watch-book2-q062.html https://xdme.com/book2-thumbs/page-062.jpg Why Does Sugar Taste Sweet? Sugar tastes sweet because your tongue has special sweet sensors. They tag sugar as a useful fuel signal. And your brain says, yum, that is good energy! https://socialmedia.xdme.com/tony/videos-book2-real/page-062.mp4 https://www.youtube.com/embed/j3tjoL4ybzI 130 2026-09-30T12:43:11+00:00 yes https://xdme.com/watch-book2-q063.html https://xdme.com/book2-thumbs/page-063.jpg Why Does Cilantro Taste Soapy to Some People? Cilantro tastes fresh and lemony to many people. But to some people, it tastes like soap. The difference is not about being picky. https://socialmedia.xdme.com/tony/videos-book2-real/page-063.mp4 https://www.youtube.com/embed/Ge8VWQKAbI0 138 2026-09-30T12:47:43+00:00 yes https://xdme.com/watch-book2-q064.html https://xdme.com/book2-thumbs/page-064.jpg Why Do We See Spots After a Bright Light? After you look at a bright light, you may see a spot that floats around. That is because the cells in your eye stay busy for a moment. The spot is called an afterimage. https://socialmedia.xdme.com/tony/videos-book2-real/page-064.mp4 https://www.youtube.com/embed/6oBeIi2eoOk 130 2026-09-30T21:52:01+00:00 yes https://xdme.com/watch-book2-q065.html https://xdme.com/book2-thumbs/page-065.jpg Why Does a Stuffed Nose Change Our Voice? When your nose is stuffy, your voice sounds different. Your voice bounces around inside the space in your nose. When that space is blocked, the sound changes. https://socialmedia.xdme.com/tony/videos-book2-real/page-065.mp4 https://www.youtube.com/embed/rs8Z9g9PRuQ 133 2026-09-30T12:54:16+00:00 yes https://xdme.com/watch-book2-q066.html https://xdme.com/book2-thumbs/page-066.jpg Why Do We Itch? An itch is a little signal that says, something is on your skin! Itch nerves tell your brain to get rid of a bug or a flake. That is why scratching feels so natural. https://socialmedia.xdme.com/tony/videos-book2-real/page-066.mp4 https://www.youtube.com/embed/caRZEWLheHA 128 2026-09-30T12:57:48+00:00 yes https://xdme.com/watch-book2-q067.html https://xdme.com/book2-thumbs/page-067.jpg Why Does Darkness Make Hearing Feel Sharper? In the dark, it feels as if your hearing gets sharper. Your ears did not change, though. Your brain simply pays more attention to sound when it cannot see much. https://socialmedia.xdme.com/tony/videos-book2-real/page-067.mp4 https://www.youtube.com/embed/AAjj9oxfbtQ 132 2026-09-30T13:03:24+00:00 yes https://xdme.com/watch-book2-q068.html https://xdme.com/book2-thumbs/page-068.jpg Why Does Perfume Smell Strong Then Fade? When you first spray perfume, the smell seems strong. But after a little while, it seems to fade away. The perfume has not gone. A new person in the room may still smell it. https://socialmedia.xdme.com/tony/videos-book2-real/page-068.mp4 https://www.youtube.com/embed/OurJxV9BsTc 128 2026-09-30T13:07:26+00:00 yes https://xdme.com/watch-book2-q069.html https://xdme.com/book2-thumbs/page-069.jpg Why Do We Feel Pain? Pain is your body's alarm system. It says, stop, protect yourself, and get help. It might not feel good, but it is there to keep you safe. https://socialmedia.xdme.com/tony/videos-book2-real/page-069.mp4 https://www.youtube.com/embed/vufD3YThk_s 131 2026-09-30T13:12:41+00:00 yes https://xdme.com/watch-book2-q070.html https://xdme.com/book2-thumbs/page-070.jpg Why Can We Balance? Balance is teamwork between your ears, your eyes, and your feet. Each one sends your brain a clue about your body. Your brain blends the clues to keep you steady. https://socialmedia.xdme.com/tony/videos-book2-real/page-070.mp4 https://www.youtube.com/embed/6nyX2Q4O8Jw 132 2026-09-30T21:55:02+00:00 yes https://xdme.com/watch-book2-q071.html https://xdme.com/book2-thumbs/page-071.jpg Why Do Sour Foods Make Us Pucker? Sour foods, like lemons, contain acid. Your tongue senses the acid, and your face reacts fast. That is why you pucker. A pucker is a reflex, not a choice. https://socialmedia.xdme.com/tony/videos-book2-real/page-071.mp4 https://www.youtube.com/embed/COhHJtTZKWI 127 2026-09-30T13:17:43+00:00 yes https://xdme.com/watch-book2-q072.html https://xdme.com/book2-thumbs/page-072.jpg Why Does Our Own Voice Sound Different? Your own voice sounds different on a recording. When you talk, you hear yourself through the air and through the bones of your skull. A recording only catches one of those paths. https://socialmedia.xdme.com/tony/videos-book2-real/page-072.mp4 https://www.youtube.com/embed/C-NMLMb8Hxc 131 2026-09-30T21:58:33+00:00 yes https://xdme.com/watch-book2-q073.html https://xdme.com/book2-thumbs/page-073.jpg Why Do Eyes Water in the Wind? Wind can make your eyes water, even when you are not sad. Wind dries the front of your eye. So your eye glands make extra tears, like windshield fluid. https://socialmedia.xdme.com/tony/videos-book2-real/page-073.mp4 https://www.youtube.com/embed/YUJjACmNwO4 129 2026-09-30T13:23:16+00:00 yes https://xdme.com/watch-book2-q074.html https://xdme.com/book2-thumbs/page-074.jpg Why Do We Have Eyebrows? Eyebrows are like little rain guards for your eyes. They catch drops of sweat or rain before they reach your eyes. They also help your face show feelings. https://socialmedia.xdme.com/tony/videos-book2-real/page-074.mp4 https://www.youtube.com/embed/bx_vivaZfCs 124 2026-09-30T22:02:34+00:00 yes https://xdme.com/watch-book2-q075.html https://xdme.com/book2-thumbs/page-075.jpg Why Do Some People Need Glasses? Some people need glasses because the picture in their eye does not land in the right spot. Glasses bend the light before it enters the eye. So the picture lands just right, and eve https://socialmedia.xdme.com/tony/videos-book2-real/page-075.mp4 https://www.youtube.com/embed/L4JWxJ_7GQg 137 2026-09-30T21:33:27+00:00 yes https://xdme.com/watch-book2-q076.html https://xdme.com/book2-thumbs/page-076.jpg Why Do We Grow? You grow because your bones get longer, following a plan inside your body. Special parts of your bones called growth plates add length while you are a kid. Good food and sleep give https://socialmedia.xdme.com/tony/videos-book2-real/page-076.mp4 https://www.youtube.com/embed/WB8lapKaYUc 131 2026-09-30T13:27:17+00:00 yes https://xdme.com/watch-book2-q077.html https://xdme.com/book2-thumbs/page-077.jpg Why Do We Lose Baby Teeth? Baby teeth are small, but your jaw grows bigger as you grow, and bigger adult teeth need room. A bigger tooth grows underneath and pushes the baby tooth out. Most kids lose about 2 https://socialmedia.xdme.com/tony/videos-book2-real/page-077.mp4 https://www.youtube.com/embed/RfRn6sHamkc 120 2026-09-30T07:16:11+00:00 yes https://xdme.com/watch-book2-q078.html https://xdme.com/book2-thumbs/page-078.jpg Why Are We a Tiny Bit Taller in the Morning? Here's a surprise! You are a tiny bit taller when you wake up than when you go to bed. Soft pads between your back bones soak up fluid while you lie down. https://socialmedia.xdme.com/tony/videos-book2-real/page-078.mp4 https://www.youtube.com/embed/X1GJDbQJI0M 121 2026-09-30T07:16:18+00:00 yes https://xdme.com/watch-book2-q079.html https://xdme.com/book2-thumbs/page-079.jpg Why Do We Need Sleep to Grow? Sleeping is not just resting. It is a busy time for your body. While you sleep, your body makes growth signals, and repairs itself. https://socialmedia.xdme.com/tony/videos-book2-real/page-079.mp4 https://www.youtube.com/embed/sOq5uPwmobM 118 2026-09-30T07:16:23+00:00 yes https://xdme.com/watch-book2-q080.html https://xdme.com/book2-thumbs/page-080.jpg Why Do Kids Have So Much Energy? Kids are always on the go, running, jumping, and playing. That is because a growing body burns fuel to move, learn, and grow, all at once. A growing body runs hot! https://socialmedia.xdme.com/tony/videos-book2-real/page-080.mp4 https://www.youtube.com/embed/4cvw1NCmLk4 118 2026-09-30T07:32:14+00:00 yes https://xdme.com/watch-book2-q081.html https://xdme.com/book2-thumbs/page-081.jpg Why Do We Get Hungry So Often? Have you ever been hungry again, just a short time after you ate? Kids burn energy on moving, learning, and growing, so they need fuel all day long. A growing engine needs fuel! https://socialmedia.xdme.com/tony/videos-book2-real/page-081.mp4 https://www.youtube.com/embed/UqcivOlKxKc 122 2026-09-30T08:02:49+00:00 yes https://xdme.com/watch-book2-q082.html https://xdme.com/book2-thumbs/page-082.jpg Why Do We Get Growing Pains? Some kids feel achy legs at night, even without getting hurt. Doctors call them growing pains, and they are common. Busy legs can ache at night! https://socialmedia.xdme.com/tony/videos-book2-real/page-082.mp4 https://www.youtube.com/embed/rM-BCx_LELo 119 2026-09-30T18:26:09+00:00 yes https://xdme.com/watch-book2-q083.html https://xdme.com/book2-thumbs/page-083.jpg Why Do We Outgrow Clothes So Fast? Have you ever pulled on a favorite shirt, and the sleeves were suddenly too short? Your bones and muscles keep getting longer, but your clothes stay exactly the same size. The body https://socialmedia.xdme.com/tony/videos-book2-real/page-083.mp4 https://www.youtube.com/embed/yc_gAumsFzI 119 2026-09-30T17:24:07+00:00 yes https://xdme.com/watch-book2-q084.html https://xdme.com/book2-thumbs/page-084.jpg Why Do Babies Have Such Big Heads? Look at a baby, and you might notice the head looks big for the body. A baby's brain is already doing huge work, and it grows very fast early on. The brain gets a head start! https://socialmedia.xdme.com/tony/videos-book2-real/page-084.mp4 https://www.youtube.com/embed/i62eMKMnBzU 113 2026-09-30T18:29:09+00:00 yes https://xdme.com/watch-book2-q085.html https://xdme.com/book2-thumbs/page-085.jpg Why Do Kids Learn So Fast? Kids pick up new words, games, and skills at amazing speed. Young brains make new links at high speed, and they love to explore. Kid brains are connection machines! https://socialmedia.xdme.com/tony/videos-book2-real/page-085.mp4 https://www.youtube.com/embed/xK8kSWkpOV0 119 2026-09-30T17:27:52+00:00 yes https://xdme.com/watch-book2-q086.html https://xdme.com/book2-thumbs/page-086.jpg Why Do We Have Belly Buttons? Everyone has one, and it is right in the middle of your tummy. Before you were born, a cord brought you food and oxygen. The belly button is the healed spot where it was. https://socialmedia.xdme.com/tony/videos-book2-real/page-086.mp4 https://www.youtube.com/embed/Jop7_gzjuJ0 114 2026-09-30T18:32:24+00:00 yes https://xdme.com/watch-book2-q087.html https://xdme.com/book2-thumbs/page-087.jpg Why Do We Look Like Our Parents? Maybe you have your mom's smile, or your dad's curly hair. Genes are like recipe cards that get passed down in families. You get a mix, not a copy. https://socialmedia.xdme.com/tony/videos-book2-real/page-087.mp4 https://www.youtube.com/embed/RRtqzCqzUi4 116 2026-09-30T17:31:53+00:00 yes https://xdme.com/watch-book2-q088.html https://xdme.com/book2-thumbs/page-088.jpg Why Do We Have Different Hair Colors? Some hair is black, some is brown, some is blond, and some is red. Melanin paints the strand! Hair can be straight, wavy, curly, or coily, and that also comes from your genes. https://socialmedia.xdme.com/tony/videos-book2-real/page-088.mp4 https://www.youtube.com/embed/-CkXF8CIrxE 120 2026-09-30T18:35:42+00:00 yes https://xdme.com/watch-book2-q089.html https://xdme.com/book2-thumbs/page-089.jpg Why Do Some Kids Grow Faster? Some kids shoot up early, and others take a little longer. Both are normal. Genes, food, sleep, and timing all play a part. Being first or last in line is usually just timing. https://socialmedia.xdme.com/tony/videos-book2-real/page-089.mp4 https://www.youtube.com/embed/gXzSDUfWzWM 121 2026-09-30T17:35:40+00:00 yes https://xdme.com/watch-book2-q090.html https://xdme.com/book2-thumbs/page-090.jpg Why Do Some Kids Need Braces? Teeth can crowd or tilt as your jaw grows. Braces guide them into place, like a map to line up your teeth. A map to line the teeth! https://socialmedia.xdme.com/tony/videos-book2-real/page-090.mp4 https://www.youtube.com/embed/adIFeouaZ90 121 2026-09-30T18:38:56+00:00 yes https://xdme.com/watch-book2-q091.html https://xdme.com/book2-thumbs/page-091.jpg Why Do We Have Fingerprints? Look closely at your fingertip, and you will see tiny swirly lines. Those ridges form before you are born, and they help you hold things. A grip pattern just for you! https://socialmedia.xdme.com/tony/videos-book2-real/page-091.mp4 https://www.youtube.com/embed/JmrW7CJiQA4 125 2026-09-30T17:39:25+00:00 yes https://xdme.com/watch-book2-q092.html https://xdme.com/book2-thumbs/page-092.jpg Why Do We Get Freckles? Freckles are tiny brown dots that can appear on skin, especially on the nose and cheeks. They are little clusters of melanin, a pigment that colors your skin. Melanin specks! https://socialmedia.xdme.com/tony/videos-book2-real/page-092.mp4 https://www.youtube.com/embed/CD6LjTWbzjI 129 2026-09-30T18:42:27+00:00 yes https://xdme.com/watch-book2-q093.html https://xdme.com/book2-thumbs/page-093.jpg Why Do Hair and Nails Keep Growing? Your hair and nails never stop growing, so we need haircuts and nail trims. Tiny factories at the root keep adding new cells. Factories at the root! https://socialmedia.xdme.com/tony/videos-book2-real/page-093.mp4 https://www.youtube.com/embed/Q1SjM5aAPIQ 114 2026-09-30T17:43:56+00:00 yes https://xdme.com/watch-book2-q094.html https://xdme.com/book2-thumbs/page-094.jpg Why Do We Shed Skin? Skin is your body's largest organ, and it is always renewing itself. Top skin cells flake off, so fresh cells can take their place. New skin from underneath! https://socialmedia.xdme.com/tony/videos-book2-real/page-094.mp4 https://www.youtube.com/embed/zaPna5h5Ih0 116 2026-09-30T18:45:44+00:00 yes https://xdme.com/watch-book2-q095.html https://xdme.com/book2-thumbs/page-095.jpg Why Are Some Kids Twins? Twins are two babies who grow at the same time, in the same parent. They can start from one egg that splits, or from two eggs at once. One start, or two! https://socialmedia.xdme.com/tony/videos-book2-real/page-095.mp4 https://www.youtube.com/embed/wBYFpjCBsyQ 124 2026-09-30T17:47:43+00:00 yes https://xdme.com/watch-book2-q096.html https://xdme.com/book2-thumbs/page-096.jpg Why Do People Have Different Skin Colors? Everyone has skin, and skin comes in many beautiful colors. Everyone has melanin, a natural pigment in their skin. Different amounts change how skin looks. https://socialmedia.xdme.com/tony/videos-book2-real/page-096.mp4 https://www.youtube.com/embed/Ywz6bwJqB2g 131 2026-09-30T18:49:15+00:00 yes https://xdme.com/watch-book2-q097.html https://xdme.com/book2-thumbs/page-097.jpg Why Do We Get Scars? When you get a cut that goes deeper than the surface, your body has to do some serious repair work. The repair crew fills the gap with extra strong fibers. A patch the body built! https://socialmedia.xdme.com/tony/videos-book2-real/page-097.mp4 https://www.youtube.com/embed/0iCEPUU1-lM 119 2026-09-30T17:51:14+00:00 yes https://xdme.com/watch-book2-q098.html https://xdme.com/book2-thumbs/page-098.jpg Why Do Growing Bones Need Calcium? Your bones are growing every day, and they need building materials. A mineral called calcium helps bones get hard and strong. Calcium is brick for bone! https://socialmedia.xdme.com/tony/videos-book2-real/page-098.mp4 https://www.youtube.com/embed/57R3IkNPziY 117 2026-09-30T18:52:30+00:00 yes https://xdme.com/watch-book2-q099.html https://xdme.com/book2-thumbs/page-099.jpg Why Do We Stop Getting Taller? You grow a lot as a kid, but after the teen years, most people stop growing taller. That is because the growth zones in your bones close up. The bone length factories shut! https://socialmedia.xdme.com/tony/videos-book2-real/page-099.mp4 https://www.youtube.com/embed/hZUC1aUvI9E 119 2026-09-30T17:54:45+00:00 yes https://xdme.com/watch-book2-q100.html https://xdme.com/book2-thumbs/page-100.jpg Why Do We Keep Changing as We Grow? You are not the same person you were a few years ago. You can do much more now! Your body, brain, and skills keep updating, and that is how you grow into the amazing person you are https://socialmedia.xdme.com/tony/videos-book2-real/page-100.mp4 https://www.youtube.com/embed/qE5JNdGEdLc 117 2026-09-30T18:55:31+00:00 yes https://xdme.com/watch-book2-q101.html https://xdme.com/book2-thumbs/page-101.jpg Why Do We Live in Families? Humans are not like some animals that can look after themselves right away. Families feed, protect, and teach kids while their brains are still building. Humans grow best with a te https://socialmedia.xdme.com/tony/videos-book2-real/page-101.mp4 https://www.youtube.com/embed/h8pe8uc0qEk 122 2026-09-30T17:58:31+00:00 yes https://xdme.com/watch-book2-q102.html https://xdme.com/book2-thumbs/page-102.jpg Why Do We Have Last Names? Lots of people share the same first name. Think about how many Alexes there are! A last name helps people keep track of families and keep records straight. https://socialmedia.xdme.com/tony/videos-book2-real/page-102.mp4 https://www.youtube.com/embed/Sy4s_SsugQ0 119 2026-09-30T18:58:47+00:00 yes https://xdme.com/watch-book2-q103.html https://xdme.com/book2-thumbs/page-103.jpg Why Do People Speak Different Languages? Around the world, people use thousands of different languages. Groups of people far apart built their own word systems. Groups invented their own codes! https://socialmedia.xdme.com/tony/videos-book2-real/page-103.mp4 https://www.youtube.com/embed/Z2DbOWZM-PY 122 2026-09-30T18:02:16+00:00 yes https://xdme.com/watch-book2-q104.html https://xdme.com/book2-thumbs/page-104.jpg Why Do We Wave Hello? When we see a friend far away, we don't need to shout. We can just wave. A wave says, I see you, and I am friendly, with no words needed. https://socialmedia.xdme.com/tony/videos-book2-real/page-104.mp4 https://www.youtube.com/embed/ZL_zftn9R2U 116 2026-09-30T19:01:48+00:00 yes https://xdme.com/watch-book2-q105.html https://xdme.com/book2-thumbs/page-105.jpg Why Do We Have Rules? Imagine a game where everybody makes up their own rules. It would be chaos! Groups make rules, so people can share space and stay safe. https://socialmedia.xdme.com/tony/videos-book2-real/page-105.mp4 https://www.youtube.com/embed/qbxJo0IZtVo 116 2026-09-30T18:05:33+00:00 yes https://xdme.com/watch-book2-q106.html https://xdme.com/book2-thumbs/page-106.jpg Why Do We Go to School? School brings teachers, books, and other kids together in one place. That helps your skills grow faster. School is a gym for the brain! https://socialmedia.xdme.com/tony/videos-book2-real/page-106.mp4 https://www.youtube.com/embed/5haM33BobrI 121 2026-09-30T19:05:03+00:00 yes https://xdme.com/watch-book2-q107.html https://xdme.com/book2-thumbs/page-107.jpg Why Do People Have Different Jobs? A baker, a nurse, a bus driver, and a teacher all keep a town working. No one can do every job, so towns work when people split the work. No one can do every job! https://socialmedia.xdme.com/tony/videos-book2-real/page-107.mp4 https://www.youtube.com/embed/5Aa8vExYJOA 122 2026-09-30T18:09:04+00:00 yes https://xdme.com/watch-book2-q108.html https://xdme.com/book2-thumbs/page-108.jpg Why Do We Use Money? Long ago, people had to trade things directly. Imagine trading a goat for a loaf of bread! Money lets you trade your work for things you need, without carrying a goat around. https://socialmedia.xdme.com/tony/videos-book2-real/page-108.mp4 https://www.youtube.com/embed/9oOENRO9hBc 120 2026-09-30T19:08:20+00:00 yes https://xdme.com/watch-book2-q109.html https://xdme.com/book2-thumbs/page-109.jpg Why Do We Celebrate Birthdays? A birthday is a special day that comes once a year. It marks one more trip around the sun. A marker on the life map! Not every culture uses cake, but the mark still matters. https://socialmedia.xdme.com/tony/videos-book2-real/page-109.mp4 https://www.youtube.com/embed/K6z9TJwJL10 120 2026-09-30T18:12:49+00:00 yes https://xdme.com/watch-book2-q110.html https://xdme.com/book2-thumbs/page-110.jpg Why Do People Wear Different Clothes? Look around, and you will see so many kinds of clothes. Fabric protects the body, and it can show who we are. Clothes match weather and meaning! https://socialmedia.xdme.com/tony/videos-book2-real/page-110.mp4 https://www.youtube.com/embed/s0uH8iHay6M 122 2026-09-30T19:11:21+00:00 yes https://xdme.com/watch-book2-q111.html https://xdme.com/book2-thumbs/page-111.jpg Why Do We Tell Stories? Stories are all around us, in books, movies, songs, and bedtime tales. A story packs facts, feelings, and warnings into one path that is easy to remember. Stories move ideas! https://socialmedia.xdme.com/tony/videos-book2-real/page-111.mp4 https://www.youtube.com/embed/ewTl5BfiE44 127 2026-09-30T18:16:20+00:00 yes https://xdme.com/watch-book2-q112.html https://xdme.com/book2-thumbs/page-112.jpg Why Do We Have Cities? Cities are places where lots of people live and work close together. They pack people in, so they can share work, tools, and ideas. Many jobs in one place! https://socialmedia.xdme.com/tony/videos-book2-real/page-112.mp4 https://www.youtube.com/embed/2OBBBH4JqTg 125 2026-09-30T19:14:41+00:00 yes https://xdme.com/watch-book2-q113.html https://xdme.com/book2-thumbs/page-113.jpg Why Do We Use Maps? The world is huge, and you can't see all of it at once. A map shrinks a big place, so your brain can plan a path. A picture of not getting lost! https://socialmedia.xdme.com/tony/videos-book2-real/page-113.mp4 https://www.youtube.com/embed/Y_hql4So3no 117 2026-09-30T18:19:51+00:00 yes https://xdme.com/watch-book2-q114.html https://xdme.com/book2-thumbs/page-114.jpg Why Do We Help People? Humans are a lot like a hiking team. Every hiker carries something, and every hiker watches out for the others. We do better when we share the effort, so each person's help matters https://socialmedia.xdme.com/tony/videos-book2-real/page-114.mp4 https://www.youtube.com/embed/63AVB37NkJI 135 2026-09-30T07:52:22+00:00 yes https://xdme.com/watch-book2-q115.html https://xdme.com/book2-thumbs/page-115.jpg Why Do We Have Teams? Have you ever tried to do a giant job all by yourself, like cleaning a whole messy house? It is really hard! A team splits the jobs into smaller pieces, so a hard goal becomes poss https://socialmedia.xdme.com/tony/videos-book2-real/page-115.mp4 https://www.youtube.com/embed/FGcwvMnHd-g 133 2026-09-30T07:21:11+00:00 yes https://xdme.com/watch-book2-q116.html https://xdme.com/book2-thumbs/page-116.jpg Why Do We Write? Have you ever had a great idea that you did not want to forget, like a funny joke or a secret recipe? Writing freezes a thought! Marks on a page let an idea travel farther than a v https://socialmedia.xdme.com/tony/videos-book2-real/page-116.mp4 https://www.youtube.com/embed/syKFLEkbleo 129 2026-09-30T08:14:30+00:00 yes https://xdme.com/watch-book2-q117.html https://xdme.com/book2-thumbs/page-117.jpg Why Do People Move to New Places? Have you ever met someone who moved to a new town? Families move for lots of different reasons. People follow their needs and hopes. https://socialmedia.xdme.com/tony/videos-book2-real/page-117.mp4 https://www.youtube.com/embed/PfK1Js_ovWc 126 2026-09-30T07:34:15+00:00 yes https://xdme.com/watch-book2-q118.html https://xdme.com/book2-thumbs/page-118.jpg Why Do We Have Holidays? Holidays are special days that people celebrate together. They give us a pause to remember together. Holidays can mark seasons, stories, and people we care about. https://socialmedia.xdme.com/tony/videos-book2-real/page-118.mp4 https://www.youtube.com/embed/o_FlzB6smZY 138 2026-09-30T07:16:35+00:00 yes https://xdme.com/watch-book2-q119.html https://xdme.com/book2-thumbs/page-119.jpg Why Do We Say Please and Thank You? Have you noticed how good it feels when someone says thank you? It makes people smile. Polite words show that you see the other person, not just the thing you want. https://socialmedia.xdme.com/tony/videos-book2-real/page-119.mp4 https://www.youtube.com/embed/ycw0WdC5ZaA 125 2026-09-30T07:16:36+00:00 yes https://xdme.com/watch-book2-q120.html https://xdme.com/book2-thumbs/page-120.jpg Why Do We Have Addresses? Imagine a street where every house looks almost the same. How would a friend find yours? An address is a code that finds your door! https://socialmedia.xdme.com/tony/videos-book2-real/page-120.mp4 https://www.youtube.com/embed/IUjW3bEmRrs 122 2026-09-30T07:42:51+00:00 yes https://xdme.com/watch-book2-q121.html https://xdme.com/book2-thumbs/page-121.jpg Why Do We Use Clocks? Have you ever been late because you were not sure what time it was? Clocks give us a shared beat for the day. They let a whole town agree on when. https://socialmedia.xdme.com/tony/videos-book2-real/page-121.mp4 https://www.youtube.com/embed/0ITFffbNVSQ 123 2026-09-30T09:55:30+00:00 yes https://xdme.com/watch-book2-q122.html https://xdme.com/book2-thumbs/page-122.jpg Why Do We Have Libraries? Books are amazing, but buying every book you want would cost a lot. A library is like a warehouse of other brains! It lets one town share thousands of books. https://socialmedia.xdme.com/tony/videos-book2-real/page-122.mp4 https://www.youtube.com/embed/t-DgdAuC2ls 125 2026-09-30T09:24:39+00:00 yes https://xdme.com/watch-book2-q123.html https://xdme.com/book2-thumbs/page-123.jpg Why Do We Work Together? Have you ever tried to lift something that was just too heavy, like a giant box or a big rock? Together we lift more! Some jobs are too big for one pair of hands. https://socialmedia.xdme.com/tony/videos-book2-real/page-123.mp4 https://www.youtube.com/embed/wrlOTQx7IGs 117 2026-09-30T09:01:45+00:00 yes https://xdme.com/watch-book2-q124.html https://xdme.com/book2-thumbs/page-124.jpg Why Do Places Have Names? Imagine trying to tell a friend about a special spot by the river, with no name to use. A name pins a place in the mind! Names let us talk about a spot without drawing it every tim https://socialmedia.xdme.com/tony/videos-book2-real/page-124.mp4 https://www.youtube.com/embed/2rDFF_BcY8U 115 2026-09-30T09:47:32+00:00 yes https://xdme.com/watch-book2-q125.html https://xdme.com/book2-thumbs/page-125.jpg Why Do We Share Food? Have you ever shared a snack with a friend, and it tasted even better? Sharing food builds the group! A shared meal feeds bodies and belonging at once. https://socialmedia.xdme.com/tony/videos-book2-real/page-125.mp4 https://www.youtube.com/embed/T2-k9nGMahw 125 2026-09-30T10:25:21+00:00 yes https://xdme.com/watch-book2-q126.html https://xdme.com/book2-thumbs/page-126.jpg Why Do We Have Day and Night? Have you ever wondered where the sun goes at night? It does not go anywhere! Earth is a spinning ball. One full spin of Earth takes about 24 hours. https://socialmedia.xdme.com/tony/videos-book2-real/page-126.mp4 https://www.youtube.com/embed/KQMN8LsSuS8 121 2026-09-30T10:16:48+00:00 yes https://xdme.com/watch-book2-q127.html https://xdme.com/book2-thumbs/page-127.jpg Why Do We Have Seasons? Why is it warm in summer and chilly in winter? Earth leans as it travels around the sun! Its tilt changes how direct the sunlight is where you live. https://socialmedia.xdme.com/tony/videos-book2-real/page-127.mp4 https://www.youtube.com/embed/pNJWjRQa2Q4 123 2026-09-30T10:39:13+00:00 yes https://xdme.com/watch-book2-q128.html https://xdme.com/book2-thumbs/page-128.jpg Why Does Weather Change? Have you noticed that one day is sunny, and the next day is rainy? Air is always on the move! Warm air, cold air, water, and wind mix in new ways every day. https://socialmedia.xdme.com/tony/videos-book2-real/page-128.mp4 https://www.youtube.com/embed/rmUWJd7-XZE 126 2026-09-30T10:33:03+00:00 yes https://xdme.com/watch-book2-q129.html https://xdme.com/book2-thumbs/page-129.jpg Why Does It Rain? Have you ever watched a big gray cloud open up and pour? Clouds get too heavy! Water rises as vapor, cools into drops, and falls. The same water has been recycling for a very long https://socialmedia.xdme.com/tony/videos-book2-real/page-129.mp4 https://www.youtube.com/embed/s1r6mnvz8Qs 127 2026-09-30T10:52:53+00:00 yes https://xdme.com/watch-book2-q130.html https://xdme.com/book2-thumbs/page-130.jpg Why Does the Wind Blow? Have you ever felt a breeze on a hot day, or flown a kite? Air rushes to fill a gap! Wind is just air on the move. A tiny breeze and a storm are both moving air. https://socialmedia.xdme.com/tony/videos-book2-real/page-130.mp4 https://www.youtube.com/embed/TF9dk7PtvBo 114 2026-09-30T10:52:22+00:00 yes https://xdme.com/watch-book2-q131.html https://xdme.com/book2-thumbs/page-131.jpg Why Are There Clouds? Have you ever looked up and found a cloud shaped like an animal? Clouds are tiny water drops in a crowd! Invisible vapor cools and clumps onto specks in the air. https://socialmedia.xdme.com/tony/videos-book2-real/page-131.mp4 https://www.youtube.com/embed/xQTYk8e7cTg 119 2026-09-30T11:05:58+00:00 yes https://xdme.com/watch-book2-q132.html https://xdme.com/book2-thumbs/page-132.jpg Why Are Oceans So Big? If you look at a globe, most of what you see is blue. That blue is ocean! Most of Earth wears water! About seven tenths of Earth is ocean. https://socialmedia.xdme.com/tony/videos-book2-real/page-132.mp4 https://www.youtube.com/embed/BeDeLlYHl1U 122 2026-09-30T11:01:57+00:00 yes https://xdme.com/watch-book2-q133.html https://xdme.com/book2-thumbs/page-133.jpg Why Do Mountains Rise? Mountains look so big and steady, but they were not always there. The crust crumples and lifts! Giant plates of crust push, and rock folds up into mountains. https://socialmedia.xdme.com/tony/videos-book2-real/page-133.mp4 https://www.youtube.com/embed/t9uDPjGSl5I 128 2026-09-30T11:14:02+00:00 yes https://xdme.com/watch-book2-q134.html https://xdme.com/book2-thumbs/page-134.jpg Why Do Rivers Flow? Have you ever watched a leaf float away down a stream? Gravity pulls water downhill! Streams join and become rivers. Rivers carve valleys as they go. Some rivers are short, and som https://socialmedia.xdme.com/tony/videos-book2-real/page-134.mp4 https://www.youtube.com/embed/cXPuen6iViE 127 2026-09-30T11:17:33+00:00 yes https://xdme.com/watch-book2-q135.html https://xdme.com/book2-thumbs/page-135.jpg Why Is Earth Round? Earth looks flat when you stand on it, but it is really a giant ball. Gravity pulled it into a ball! Gravity pulls every bit of a big planet toward the center. https://socialmedia.xdme.com/tony/videos-book2-real/page-135.mp4 https://www.youtube.com/embed/LCxMobd_Nt8 120 2026-09-30T11:31:38+00:00 yes https://xdme.com/watch-book2-q136.html https://xdme.com/book2-thumbs/page-136.jpg Why Do Things Fall Down? When you drop a ball, it always falls to the ground. Have you ever wondered why? Gravity is a pull toward Earth! The moon has gravity too, just weaker. https://socialmedia.xdme.com/tony/videos-book2-real/page-136.mp4 https://www.youtube.com/embed/E37CmdtoeGo 117 2026-09-30T11:25:06+00:00 yes https://xdme.com/watch-book2-q137.html https://xdme.com/book2-thumbs/page-137.jpg Why Does the Moon Change Shape? Sometimes the moon looks like a big circle, and sometimes like a thin banana. The sun lights different slices! The moon is a ball, and we see the part the sun is lighting. https://socialmedia.xdme.com/tony/videos-book2-real/page-137.mp4 https://www.youtube.com/embed/GAbcSEIchoU 113 2026-09-30T11:39:42+00:00 yes https://xdme.com/watch-book2-q138.html https://xdme.com/book2-thumbs/page-138.jpg Why Do Stars Look So Small? On a clear night, stars look like tiny sparkles. But they are not tiny at all! They are suns, just very far away! Our sun is a star. It looks big because it is close. https://socialmedia.xdme.com/tony/videos-book2-real/page-138.mp4 https://www.youtube.com/embed/3Cr3H06ThdY 123 2026-09-30T11:39:11+00:00 yes https://xdme.com/watch-book2-q139.html https://xdme.com/book2-thumbs/page-139.jpg Why Is the Sky Blue? Look up on a sunny day. The sky is a beautiful blue! Why? Space is black because there is almost no air to scatter light. The same idea explains why sunsets can look red, which we https://socialmedia.xdme.com/tony/videos-book2-real/page-139.mp4 https://www.youtube.com/embed/rOsmk8TfRlw 125 2026-09-30T11:49:16+00:00 yes https://xdme.com/watch-book2-q140.html https://xdme.com/book2-thumbs/page-140.jpg Why Are Sunsets Orange and Pink? Have you ever watched the sun go down and seen the sky turn orange and pink? Light takes a longer path! At sunset, sunlight travels through more air, and blue gets scattered away. https://socialmedia.xdme.com/tony/videos-book2-real/page-140.mp4 https://www.youtube.com/embed/udEAeiUfv3o 121 2026-09-30T11:46:15+00:00 yes https://xdme.com/watch-book2-q141.html https://xdme.com/book2-thumbs/page-141.jpg Why Do Volcanoes Erupt? Volcanoes can look scary, but there is a simple reason they erupt. Hot rock finds a door! Deep rock can melt, and melted rock rises and may push out. https://socialmedia.xdme.com/tony/videos-book2-real/page-141.mp4 https://www.youtube.com/embed/gVfDJtr96tQ 128 2026-09-30T11:55:49+00:00 yes https://xdme.com/watch-book2-q142.html https://xdme.com/book2-thumbs/page-142.jpg Why Does the Ground Shake? Sometimes the ground trembles. That is called an earthquake. Giant plates can slip! Most shakes are small. Some places have earthquakes more often than others, mostly near the edge https://socialmedia.xdme.com/tony/videos-book2-real/page-142.mp4 https://www.youtube.com/embed/SDFk8F3SPNQ 130 2026-09-30T11:50:47+00:00 yes https://xdme.com/watch-book2-q143.html https://xdme.com/book2-thumbs/page-143.jpg Why Do We Find Fossils? Have you ever seen a fossil, like a stone shell or a dinosaur bone? Old life left a stamp! A plant or animal can get buried, and minerals replace its shape in rock. https://socialmedia.xdme.com/tony/videos-book2-real/page-143.mp4 https://www.youtube.com/embed/BDX97wJ25s4 129 2026-09-30T12:00:51+00:00 yes https://xdme.com/watch-book2-q144.html https://xdme.com/book2-thumbs/page-144.jpg Why Do Trees Help Us Breathe? Take a deep breath. Part of that fresh air came from plants! Leaves trade gases! Forests are giant air helpers, but not the only ones. A single big tree can make enough oxygen for https://socialmedia.xdme.com/tony/videos-book2-real/page-144.mp4 https://www.youtube.com/embed/E3KbILYqy8o 125 2026-09-30T11:56:19+00:00 yes https://xdme.com/watch-book2-q145.html https://xdme.com/book2-thumbs/page-145.jpg Why Do We Recycle? When you finish a juice box or a bottle, what should you do with it? Old stuff can be new stuff! Recycling turns used material into fresh material, so we dig and cut less. https://socialmedia.xdme.com/tony/videos-book2-real/page-145.mp4 https://www.youtube.com/embed/fIX3BDI5uhI 129 2026-09-30T12:12:26+00:00 yes https://xdme.com/watch-book2-q146.html https://xdme.com/book2-thumbs/page-146.jpg Where Does Trash Go? After you throw something away, where does it go? It does not vanish! Trash is collected, sorted, buried, burned, or remade. Less trash starts with using less. https://socialmedia.xdme.com/tony/videos-book2-real/page-146.mp4 https://www.youtube.com/embed/Iwp2quwteq8 118 2026-09-30T12:02:52+00:00 yes https://xdme.com/watch-book2-q147.html https://xdme.com/book2-thumbs/page-147.jpg Why Do We Need World Maps? Imagine trying to see the whole Earth at once. It is far too big! A map of the whole ball! Every flat map stretches some parts a little. https://socialmedia.xdme.com/tony/videos-book2-real/page-147.mp4 https://www.youtube.com/embed/e-Oybdh666k 117 2026-09-30T12:17:28+00:00 yes https://xdme.com/watch-book2-q148.html https://xdme.com/book2-thumbs/page-148.jpg Why Do Clocks Disagree Around the World? If it is noon where you are, it can be the middle of the night somewhere else! Earth is round and spinning. When it is noon on your side, it is night on the far side. https://socialmedia.xdme.com/tony/videos-book2-real/page-148.mp4 https://www.youtube.com/embed/W2uqtSLjwKM 118 2026-09-30T12:07:54+00:00 yes https://xdme.com/watch-book2-q149.html https://xdme.com/book2-thumbs/page-149.jpg Why Do People Explore? People have always wanted to see what is over the next hill. Curiosity plus a plan! Humans map new places to find food, safety, and answers. https://socialmedia.xdme.com/tony/videos-book2-real/page-149.mp4 https://www.youtube.com/embed/wlobJeUVfYo 131 2026-09-30T12:27:33+00:00 yes https://xdme.com/watch-book2-q150.html https://xdme.com/book2-thumbs/page-150.jpg Why Should We Take Care of Earth? Earth is the only home we have! Everything we need comes from it. Air, water, soil, and living things are a shared kit. Small habits add up, like less waste, more trees, and cleane https://socialmedia.xdme.com/tony/videos-book2-real/page-150.mp4 https://www.youtube.com/embed/f5OShwEP-bA 118 2026-09-30T12:13:27+00:00 yes https://xdme.com/watch-book3-q001.html https://xdme.com/book3-thumbs/page-001.jpg Why Do Bikes Stay Up When You Ride? A moving bike stays up because its wheels spin and you keep making tiny steers. A bike standing still just tips over, because nothing is holding it up. But a rolling bike gets smal https://socialmedia.xdme.com/tony/videos-book3/page-001.mp4 https://www.youtube.com/embed/EaNlCQSG1hg 121 2026-09-29T21:01:41+00:00 yes https://xdme.com/watch-book3-q002.html https://xdme.com/book3-thumbs/page-002.jpg Why Do Airplanes Stay in the Sky? A plane wing is curved on top and flatter underneath. When air rushes over that shape, the wing gets an upward push called lift. Fast air over a wing makes lift, and when lift beat https://socialmedia.xdme.com/tony/videos-book3/page-002.mp4 https://www.youtube.com/embed/TtcCNZXuxYs 143 2026-09-29T21:01:42+00:00 yes https://xdme.com/watch-book3-q003.html https://xdme.com/book3-thumbs/page-003.jpg Why Do Boats Float? Floating is a push contest. If that upward push is at least as big as the boat's weight, the boat floats! https://socialmedia.xdme.com/tony/videos-book3/page-003.mp4 https://www.youtube.com/embed/SmEv2ZlBRSA 126 2026-09-29T21:01:45+00:00 yes https://xdme.com/watch-book3-q004.html https://xdme.com/book3-thumbs/page-004.jpg Why Do Wheels Beat Dragging? A wheel touches the ground with only a tiny patch. Dragging is a long scrape, but rolling is a tiny touch. That means much less rubbing, so your load moves with a lot less effort! https://socialmedia.xdme.com/tony/videos-book3/page-004.mp4 https://www.youtube.com/embed/o0Bw_-86rJ8 133 2026-09-29T21:01:47+00:00 yes https://xdme.com/watch-book3-q005.html https://xdme.com/book3-thumbs/page-005.jpg Why Do Paper Airplanes Fly? A paper plane is really a tiny wing that you throw. The paper is both the body and the wing, and your throw gives it speed. Air flows over the wide paper wings, and that helps the https://socialmedia.xdme.com/tony/videos-book3/page-005.mp4 https://www.youtube.com/embed/DKx5NutvpAk 132 2026-09-29T21:01:48+00:00 yes https://xdme.com/watch-book3-q006.html https://xdme.com/book3-thumbs/page-006.jpg Why Do Trains Need Tracks? A train wheel is steel, and the rail is steel too. Smooth steel rolling on steel has very little rub, so heavy trains can roll easily. And the tracks show the train exactly where t https://socialmedia.xdme.com/tony/videos-book3/page-006.mp4 https://www.youtube.com/embed/4VHHZ7EnIgE 134 2026-09-29T21:01:49+00:00 yes https://xdme.com/watch-book3-q007.html https://xdme.com/book3-thumbs/page-007.jpg Why Do Helicopters Hover? Helicopter blades are wings. Spinning blades are long, thin wings, and as they whirl, they make lift. When the lift matches the helicopter's weight, it can hover in one place! https://socialmedia.xdme.com/tony/videos-book3/page-007.mp4 https://www.youtube.com/embed/jxwccv_wZMY 137 2026-09-29T21:01:50+00:00 yes https://xdme.com/watch-book3-q008.html https://xdme.com/book3-thumbs/page-008.jpg Why Do Cars Need Brakes? A moving car has lots of energy. Brakes squeeze a spinning disc, and the rubbing makes heat. That turns the car's speed into warmth, and the car slows down. https://socialmedia.xdme.com/tony/videos-book3/page-008.mp4 https://www.youtube.com/embed/hStj4DE17Ck 131 2026-09-29T21:01:56+00:00 yes https://xdme.com/watch-book3-q009.html https://xdme.com/book3-thumbs/page-009.jpg Why Is a Ship Pointed in Front? The front of a ship is called the bow. A sharp bow cuts the water instead of shoving a wall of it. That means less drag and less fuel. https://socialmedia.xdme.com/tony/videos-book3/page-009.mp4 https://www.youtube.com/embed/uMSnvpm9Om4 130 2026-09-29T21:21:18+00:00 yes https://xdme.com/watch-book3-q010.html https://xdme.com/book3-thumbs/page-010.jpg Why Do Hot Air Balloons Go Up? Heat makes the air molecules spread out. So the same bag of hot air weighs less than the cool air around it. Cool air pushes the lighter bag up, and the balloon rises! https://socialmedia.xdme.com/tony/videos-book3/page-010.mp4 https://www.youtube.com/embed/s-JWTpfrFKc 131 2026-09-29T21:41:23+00:00 yes https://xdme.com/watch-book3-q011.html https://xdme.com/book3-thumbs/page-011.jpg Why Do Tires Have Treads? Rain makes a thin film of water on the road. Tread grooves cut paths, so the water can shoot out. Then the rubber can grip the road instead of surfing on the water! https://socialmedia.xdme.com/tony/videos-book3/page-011.mp4 https://www.youtube.com/embed/WUkFBjqBAtk 129 2026-09-29T22:00:58+00:00 yes https://xdme.com/watch-book3-q012.html https://xdme.com/book3-thumbs/page-012.jpg Why Do Planes Have Flaps? A flap is a hinged panel on the back of the wing. When the pilot drops it, the wing becomes bigger and more curved. That makes more lift at slow speed, which is exactly what a plan https://socialmedia.xdme.com/tony/videos-book3/page-012.mp4 https://www.youtube.com/embed/o1-rSXatYz4 134 2026-09-29T22:20:32+00:00 yes https://xdme.com/watch-book3-q013.html https://xdme.com/book3-thumbs/page-013.jpg Why Do Submarines Sink and Rise? A submarine has special ballast tanks. Fill them with water, and the craft gets heavier and sinks. Blow the water out with air, and it gets lighter and rises! https://socialmedia.xdme.com/tony/videos-book3/page-013.mp4 https://www.youtube.com/embed/jezwSSHKtYs 134 2026-09-29T22:41:38+00:00 yes https://xdme.com/watch-book3-q014.html https://xdme.com/book3-thumbs/page-014.jpg Why Do Bikes Have Gears? Gears change how far the bike goes for each turn of the pedals. A low gear is small steps, and a high gear is long steps. Low gears help on hills, and high gears help with speed! https://socialmedia.xdme.com/tony/videos-book3/page-014.mp4 https://www.youtube.com/embed/nHBcim8-dJE 130 2026-09-29T23:00:12+00:00 yes https://xdme.com/watch-book3-q015.html https://xdme.com/book3-thumbs/page-015.jpg Why Do Rockets Need Fire? A rocket burns fuel and throws hot gas out of the bottom. Every action has a push back, so when the gas goes down, the rocket goes up! It even works in empty space. https://socialmedia.xdme.com/tony/videos-book3/page-015.mp4 https://www.youtube.com/embed/5j-vbc8Jo3w 127 2026-09-29T23:22:18+00:00 yes https://xdme.com/watch-book3-q016.html https://xdme.com/book3-thumbs/page-016.jpg Why Do Cars Have Seatbelts? When a car stops fast, your body still wants to keep going. A seatbelt holds you to the seat, so you do not fly forward. It spreads the stopping force across your strong hips and c https://socialmedia.xdme.com/tony/videos-book3/page-016.mp4 https://www.youtube.com/embed/41xKNKBDTnQ 129 2026-09-29T23:41:52+00:00 yes https://xdme.com/watch-book3-q017.html https://xdme.com/book3-thumbs/page-017.jpg Why Do Airplanes Have Propellers? A propeller is a set of twisted blades. When they spin, they shove air backward, and the plane is pulled or pushed forward. It's like a fan that moves the whole airplane! https://socialmedia.xdme.com/tony/videos-book3/page-017.mp4 https://www.youtube.com/embed/JbIlVIGBOvM 128 2026-09-30T00:02:31+00:00 yes https://xdme.com/watch-book3-q018.html https://xdme.com/book3-thumbs/page-018.jpg Why Do Sailboats Need Wind? Sails catch moving air, and the wind can push the boat from behind. Wind can also flow over a curved sail and pull it forward. That's why a sail works like a vertical wing! https://socialmedia.xdme.com/tony/videos-book3/page-018.mp4 https://www.youtube.com/embed/zd1iI7U8FYA 131 2026-09-30T00:23:22+00:00 yes https://xdme.com/watch-book3-q019.html https://xdme.com/book3-thumbs/page-019.jpg Why Do Skateboards Roll? A skateboard turns a push or a downhill slope into a smooth roll. The wheels spin with very little rub, thanks to bearings hidden inside. Four small wheels plus gravity and a push https://socialmedia.xdme.com/tony/videos-book3/page-019.mp4 https://www.youtube.com/embed/xWNu7dMjceM 131 2026-09-30T00:41:56+00:00 yes https://xdme.com/watch-book3-q020.html https://xdme.com/book3-thumbs/page-020.jpg Why Do Parachutes Work? A parachute is a giant air brake. It makes a wide surface that slams into many air molecules, so the fall slows down to a safe speed. The canopy also traps a cushion of air underne https://socialmedia.xdme.com/tony/videos-book3/page-020.mp4 https://www.youtube.com/embed/pUDoTsTUYyw 134 2026-09-30T00:56:01+00:00 yes https://xdme.com/watch-book3-q021.html https://xdme.com/book3-thumbs/page-021.jpg Why Do Trucks Have So Many Wheels? A loaded truck can weigh as much as many cars. Extra wheels spread that weight over more patches of pavement. More wheels share the weight, so the road does not crack! https://socialmedia.xdme.com/tony/videos-book3/page-021.mp4 https://www.youtube.com/embed/RC9sCewYUhA 129 2026-09-30T01:09:04+00:00 yes https://xdme.com/watch-book3-q022.html https://xdme.com/book3-thumbs/page-022.jpg Why Do Gliders Fly with No Engine? A glider is a plane with no engine. It trades height for forward speed, then finds rising air to climb again. Long wings ride rising air, the way a hawk does! https://socialmedia.xdme.com/tony/videos-book3/page-022.mp4 https://www.youtube.com/embed/54qUrnZ6Z5E 138 2026-09-30T01:23:10+00:00 yes https://xdme.com/watch-book3-q023.html https://xdme.com/book3-thumbs/page-023.jpg Why Do Cars Have Headlights? Headlights throw a beam of light, so the driver can see the road, signs, and animals after dark. They also warn other people that you are coming. Lights let you see the road, and t https://socialmedia.xdme.com/tony/videos-book3/page-023.mp4 https://www.youtube.com/embed/BQdzP4c2JV4 130 2026-09-30T05:24:33+00:00 yes https://xdme.com/watch-book3-q024.html https://xdme.com/book3-thumbs/page-024.jpg Why Do Tunnels Go Through Mountains? Going over a mountain costs time, fuel, and steep roads. A tunnel cuts a nearly flat path through the rock. A tunnel is a shortcut through the mountain, instead of over it! https://socialmedia.xdme.com/tony/videos-book3/page-024.mp4 https://www.youtube.com/embed/vFotlnoyMVE 127 2026-09-30T02:58:31+00:00 yes https://xdme.com/watch-book3-q025.html https://xdme.com/book3-thumbs/page-025.jpg Why Do Boats Have Rudders? A rudder is a flat fin at the back of a boat. When you angle it, flowing water pushes the stern sideways, and the bow turns. A rudder is an underwater door that steers the whole sh https://socialmedia.xdme.com/tony/videos-book3/page-025.mp4 https://www.youtube.com/embed/TLNlJFP9mcY 126 2026-09-30T06:57:53+00:00 yes https://xdme.com/watch-book3-q026.html https://xdme.com/book3-thumbs/page-026.jpg Why Do Lights Turn on with a Switch? A light needs a complete loop of wire from the power source and back. A switch opens or closes that loop. A switch is a tiny gate that opens the path for electricity! https://socialmedia.xdme.com/tony/videos-book3/page-026.mp4 https://www.youtube.com/embed/HizpJY4UTnY 133 2026-09-30T07:52:54+00:00 yes https://xdme.com/watch-book3-q027.html https://xdme.com/book3-thumbs/page-027.jpg Why Do Batteries Die? A battery stores energy in chemicals. When you use it, those chemicals change. When the useful chemicals run out, the battery dies. https://socialmedia.xdme.com/tony/videos-book3/page-027.mp4 https://www.youtube.com/embed/71NZ3aoGWJw 135 2026-09-30T03:20:39+00:00 yes https://xdme.com/watch-book3-q028.html https://xdme.com/book3-thumbs/page-028.jpg Why Is Fire Hot? Fire is a rapid reaction between fuel and oxygen. Breaking and making chemical bonds releases energy. In a flame, that energy flies out as heat and light. https://socialmedia.xdme.com/tony/videos-book3/page-028.mp4 https://www.youtube.com/embed/YAAYnMTL1pM 138 2026-09-30T03:31:12+00:00 yes https://xdme.com/watch-book3-q029.html https://xdme.com/book3-thumbs/page-029.jpg Why Do Magnets Stick? A magnet makes an invisible field. Iron, nickel, and some steels feel that field and get pulled in. Inside the magnet, many tiny spinning electrons line up and pull on iron! https://socialmedia.xdme.com/tony/videos-book3/page-029.mp4 https://www.youtube.com/embed/0yladVb0JCY 130 2026-09-30T03:41:16+00:00 yes https://xdme.com/watch-book3-q030.html https://xdme.com/book3-thumbs/page-030.jpg Why Do Solar Panels Work? A solar panel is a sandwich of special silicon. Light packets called photons knock electrons free, so they can flow as current. Sunlight knocks electrons loose, and that flow is el https://socialmedia.xdme.com/tony/videos-book3/page-030.mp4 https://www.youtube.com/embed/_lIvMvXEe-Q 129 2026-09-30T03:55:52+00:00 yes https://xdme.com/watch-book3-q031.html https://xdme.com/book3-thumbs/page-031.jpg Why Do We See Lightning Before Thunder? Lightning and thunder start together. Light reaches your eyes almost instantly. Sound needs time to cross the air. https://socialmedia.xdme.com/tony/videos-book3/page-031.mp4 https://www.youtube.com/embed/-oUufqPsEaQ 133 2026-09-30T04:06:27+00:00 yes https://xdme.com/watch-book3-q032.html https://xdme.com/book3-thumbs/page-032.jpg Why Does Static Make Hair Stick Up? Rubbing moves electrons from one thing to another. That leaves things with an electric charge. Hairs with the same charge push away from each other and from your head, so hair stan https://socialmedia.xdme.com/tony/videos-book3/page-032.mp4 https://www.youtube.com/embed/FY8X9iBgIeY 132 2026-09-30T04:11:29+00:00 yes https://xdme.com/watch-book3-q033.html https://xdme.com/book3-thumbs/page-033.jpg Why Do Phones Need Charging? Your phone stores energy in a rechargeable battery. The screen, radio, and chips spend that energy, and charging puts energy back in. A phone battery is a refillable snack, and app https://socialmedia.xdme.com/tony/videos-book3/page-033.mp4 https://www.youtube.com/embed/RNulzRYGl0Y 128 2026-09-30T06:25:00+00:00 yes https://xdme.com/watch-book3-q034.html https://xdme.com/book3-thumbs/page-034.jpg Why Do Light Bulbs Get Warm? A bulb turns electric energy into light. Not all the electricity becomes light. Some becomes leftover heat! https://socialmedia.xdme.com/tony/videos-book3/page-034.mp4 https://www.youtube.com/embed/t37bVkndDRQ 133 2026-09-30T04:33:38+00:00 yes https://xdme.com/watch-book3-q035.html https://xdme.com/book3-thumbs/page-035.jpg Why Does Ice Melt? Ice is water locked in a crystal. Add heat, and the bits jiggle hard enough to slip free. That is melting. https://socialmedia.xdme.com/tony/videos-book3/page-035.mp4 https://www.youtube.com/embed/yjeJZZmO3eE 126 2026-09-30T06:38:06+00:00 yes https://xdme.com/watch-book3-q036.html https://xdme.com/book3-thumbs/page-036.jpg Why Do Fans Cool Us? A fan blows room air across your skin. Sweat evaporates faster, and evaporating water takes heat with it, so you feel cooler. A fan does not make cold air. https://socialmedia.xdme.com/tony/videos-book3/page-036.mp4 https://www.youtube.com/embed/HOSnGtrahyM 125 2026-09-30T04:51:45+00:00 yes https://xdme.com/watch-book3-q037.html https://xdme.com/book3-thumbs/page-037.jpg Why Is a Toaster Hot? Inside a toaster, thin metal wires resist the electric current. That resistance turns electric energy into glowing heat that browns bread. Wires glow because electricity has a hard https://socialmedia.xdme.com/tony/videos-book3/page-037.mp4 https://www.youtube.com/embed/HjhD7qUP0Uc 133 2026-09-30T05:04:51+00:00 yes https://xdme.com/watch-book3-q038.html https://xdme.com/book3-thumbs/page-038.jpg Why Does a Kettle Whistle? Boiling water makes steam. The steam must escape through a small spout hole. Fast steam wobbles the air, and that wobble is a whistle. https://socialmedia.xdme.com/tony/videos-book3/page-038.mp4 https://www.youtube.com/embed/Mh4EO2WpbLI 134 2026-09-30T05:14:27+00:00 yes https://xdme.com/watch-book3-q039.html https://xdme.com/book3-thumbs/page-039.jpg Why Do Fireworks Have Colors? Fireworks are packed shells full of tiny chemical pellets called stars. When those pellets burn, special metal salts glow in bright colors. Each metal paints the sky a different co https://socialmedia.xdme.com/tony/videos-book3/page-039.mp4 https://www.youtube.com/embed/KHomyBlpO64 125 2026-09-29T21:01:57+00:00 yes https://xdme.com/watch-book3-q040.html https://xdme.com/book3-thumbs/page-040.jpg Why Does a Compass Point North? A compass needle is a tiny magnet that can spin freely. And guess what? Our whole planet is a giant, weak magnet, too! https://socialmedia.xdme.com/tony/videos-book3/page-040.mp4 https://www.youtube.com/embed/Ld9mo1R2RZg 121 2026-09-29T21:02:09+00:00 yes https://xdme.com/watch-book3-q041.html https://xdme.com/book3-thumbs/page-041.jpg Why Does a Microwave Heat Food? A microwave oven makes short radio waves, called microwaves. Those invisible waves make the water molecules in your food wiggle and spin. Wiggling molecules bump into their neighbo https://socialmedia.xdme.com/tony/videos-book3/page-041.mp4 https://www.youtube.com/embed/gScTR7VCSZE 125 2026-09-29T21:02:13+00:00 yes https://xdme.com/watch-book3-q042.html https://xdme.com/book3-thumbs/page-042.jpg Why Do LED Lights Use Less Power? An LED makes light inside a tiny chip, so almost no energy is thrown away as heat. An old-fashioned bulb glows by heating a thin wire until it's white hot, and that wastes lots of https://socialmedia.xdme.com/tony/videos-book3/page-042.mp4 https://www.youtube.com/embed/TlOTCgYFDeY 126 2026-09-29T21:02:18+00:00 yes https://xdme.com/watch-book3-q043.html https://xdme.com/book3-thumbs/page-043.jpg Why Does Rubbing Hands Make Heat? When you rub your hands together, the rough surfaces grab and slip against each other. That tug-of-war is called friction. Friction turns the energy of your moving hands into heat. https://socialmedia.xdme.com/tony/videos-book3/page-043.mp4 https://www.youtube.com/embed/GYtWPReYDHI 115 2026-09-29T21:02:20+00:00 yes https://xdme.com/watch-book3-q044.html https://xdme.com/book3-thumbs/page-044.jpg Why Does Steam Rise? Steam is water that has turned into a gas. Heat makes water molecules fly apart, so hot steam is lighter than the cool air around it. And lighter stuff floats up, like a bubble! https://socialmedia.xdme.com/tony/videos-book3/page-044.mp4 https://www.youtube.com/embed/xYgzkAzhK9U 117 2026-09-29T21:02:21+00:00 yes https://xdme.com/watch-book3-q045.html https://xdme.com/book3-thumbs/page-045.jpg Why Do Plugs Have Three Prongs? Two of a plug's prongs carry electric current in and out, like a round trip. The third prong is a ground wire. It's a safety escape path for electricity! https://socialmedia.xdme.com/tony/videos-book3/page-045.mp4 https://www.youtube.com/embed/ZkzXEC2Yif8 123 2026-09-29T21:02:22+00:00 yes https://xdme.com/watch-book3-q046.html https://xdme.com/book3-thumbs/page-046.jpg Why Do Power Lines Hum? Power lines carry alternating current, which rushes back and forth in the wire. In many countries, it flips direction 60 times every second. In others, it's 50 times! https://socialmedia.xdme.com/tony/videos-book3/page-046.mp4 https://www.youtube.com/embed/BrKl_28MTl4 120 2026-09-29T21:21:19+00:00 yes https://xdme.com/watch-book3-q047.html https://xdme.com/book3-thumbs/page-047.jpg Why Does a Fridge Stay Cold? A fridge doesn't make cold. It pumps heat out of the box! Cold is just less heat. https://socialmedia.xdme.com/tony/videos-book3/page-047.mp4 https://www.youtube.com/embed/tOYh2s1k0IY 118 2026-09-29T21:40:52+00:00 yes https://xdme.com/watch-book3-q048.html https://xdme.com/book3-thumbs/page-048.jpg Why Do Shadows Happen? A shadow is just a place the light could not reach! Light travels in straight lines. When an object blocks those lines, the space behind it stays dark. https://socialmedia.xdme.com/tony/videos-book3/page-048.mp4 https://www.youtube.com/embed/iiWTwqFQWKA 118 2026-09-29T22:00:59+00:00 yes https://xdme.com/watch-book3-q049.html https://xdme.com/book3-thumbs/page-049.jpg Why Is the Sun So Bright? The Sun is a giant ball of hot gas, like a huge fusion lamp! Deep in its core, hydrogen slams together and becomes helium. That fusion dumps huge energy as light and heat. https://socialmedia.xdme.com/tony/videos-book3/page-049.mp4 https://www.youtube.com/embed/0HOlVhCHpCM 123 2026-09-29T22:20:33+00:00 yes https://xdme.com/watch-book3-q050.html https://xdme.com/book3-thumbs/page-050.jpg Why Does a Candle Melt? Candle wax is a solid fuel. The flame melts the wax nearby into a liquid. The wick soaks up that liquid, and the flame burns it as vapor. https://socialmedia.xdme.com/tony/videos-book3/page-050.mp4 https://www.youtube.com/embed/PD2hYAUmFpM 117 2026-09-29T22:41:07+00:00 yes https://xdme.com/watch-book3-q051.html https://xdme.com/book3-thumbs/page-051.jpg Why Do Buildings Have Foundations? A foundation is the hidden bottom of a building. It spreads the weight out, so the house does not sink or tip over. Think of it as a giant, buried foot! https://socialmedia.xdme.com/tony/videos-book3/page-051.mp4 https://www.youtube.com/embed/HOQh8230Q8Y 117 2026-09-29T23:02:43+00:00 yes https://xdme.com/watch-book3-q052.html https://xdme.com/book3-thumbs/page-052.jpg Why Do Bridges Have Arches? An arch is a curved stack of stones or concrete. Weight from above squeezes the pieces together, instead of snapping them. That's why arches can be so strong! https://socialmedia.xdme.com/tony/videos-book3/page-052.mp4 https://www.youtube.com/embed/5SAF9inDq-Q 120 2026-09-29T23:21:17+00:00 yes https://xdme.com/watch-book3-q053.html https://xdme.com/book3-thumbs/page-053.jpg Why Do Skyscrapers Sway? Tall buildings are designed to bend a little, in wind and in earthquakes. A stiff tower would crack, but a gentle sway safely dumps the energy. So skyscrapers really do move! https://socialmedia.xdme.com/tony/videos-book3/page-053.mp4 https://www.youtube.com/embed/yWt3jKaljUA 118 2026-09-29T23:42:24+00:00 yes https://xdme.com/watch-book3-q054.html https://xdme.com/book3-thumbs/page-054.jpg Why Is Concrete So Strong? Concrete is a mix of cement, sand, gravel, and water. It hardens into a kind of artificial rock, and it loves being squeezed! Let's see how it gets so tough. https://socialmedia.xdme.com/tony/videos-book3/page-054.mp4 https://www.youtube.com/embed/xxEwWpMntyc 120 2026-09-30T00:02:32+00:00 yes https://xdme.com/watch-book3-q055.html https://xdme.com/book3-thumbs/page-055.jpg Why Do Houses Have Sloped Roofs? A sloped roof is a slide for rain and snow. Water runs off, instead of pooling and leaking through the ceiling. Slopes keep our houses dry! https://socialmedia.xdme.com/tony/videos-book3/page-055.mp4 https://www.youtube.com/embed/bUdeEbTyiPU 117 2026-09-30T00:22:51+00:00 yes https://xdme.com/watch-book3-q056.html https://xdme.com/book3-thumbs/page-056.jpg Why Do Windows Have Glass? Glass lets light in, and keeps weather out. It's a hard, see-through wall, made mostly of melted sand! Let's see how windows are made. https://socialmedia.xdme.com/tony/videos-book3/page-056.mp4 https://www.youtube.com/embed/uCLzA7DrVzw 118 2026-09-30T00:42:27+00:00 yes https://xdme.com/watch-book3-q057.html https://xdme.com/book3-thumbs/page-057.jpg Why Do Doors Have Hinges? A hinge is a tiny axle that lets a heavy door swing. Without it, you'd have to lift the whole door off the wall! Two metal plates share one pin, and that's the trick. https://socialmedia.xdme.com/tony/videos-book3/page-057.mp4 https://www.youtube.com/embed/X5GkNVwbwAA 118 2026-09-30T00:55:30+00:00 yes https://xdme.com/watch-book3-q058.html https://xdme.com/book3-thumbs/page-058.jpg Why Do Stairs Have Railings? A railing is a second path for your hand. If a foot slips, your arm can still catch the fall. So railings help keep us safe on stairs! https://socialmedia.xdme.com/tony/videos-book3/page-058.mp4 https://www.youtube.com/embed/btYqk16woVo 118 2026-09-30T01:09:05+00:00 yes https://xdme.com/watch-book3-q059.html https://xdme.com/book3-thumbs/page-059.jpg Why Do Chimneys Go Up? Hot smoke is lighter than cool air, so it rises. A tall chimney is a one-way tube that gives that rising air a path out of the house. Let's find out how it works! https://socialmedia.xdme.com/tony/videos-book3/page-059.mp4 https://www.youtube.com/embed/kveDTDXdPhY 118 2026-09-30T01:22:39+00:00 yes https://xdme.com/watch-book3-q060.html https://xdme.com/book3-thumbs/page-060.jpg Why Do Buildings Have Elevators? An elevator is a moving room that climbs a shaft. So people don't have to walk up 40 flights of stairs! A control brain picks the next floor. https://socialmedia.xdme.com/tony/videos-book3/page-060.mp4 https://www.youtube.com/embed/9p8eVgPvdVo 118 2026-09-30T08:10:27+00:00 yes https://xdme.com/watch-book3-q061.html https://xdme.com/book3-thumbs/page-061.jpg Why Do Suspension Bridges Use Cables? Giant cables hang from tall towers, and hold the road like a hammock. The cables take the stretch, so the road doesn't sag into the water. That's why suspension bridges use cables! https://socialmedia.xdme.com/tony/videos-book3/page-061.mp4 https://www.youtube.com/embed/vwTD4nikSGE 117 2026-09-30T03:14:36+00:00 yes https://xdme.com/watch-book3-q062.html https://xdme.com/book3-thumbs/page-062.jpg Why Do Tunnels Have Lining? A tunnel lining is a hard inner shell. After workers bore a hole, the lining keeps soil and water from falling in. It's like a strong tube inside the ground! https://socialmedia.xdme.com/tony/videos-book3/page-062.mp4 https://www.youtube.com/embed/HOjeOXp3TWE 118 2026-09-30T07:32:47+00:00 yes https://xdme.com/watch-book3-q063.html https://xdme.com/book3-thumbs/page-063.jpg Why Do Walls Use Bricks? A brick is a small baked block. Stacked with staggered joints and sticky mortar, many little blocks become one strong wall. Let's see how a brick wall happens! https://socialmedia.xdme.com/tony/videos-book3/page-063.mp4 https://www.youtube.com/embed/saw4Wv_j-1A 117 2026-09-30T03:36:13+00:00 yes https://xdme.com/watch-book3-q064.html https://xdme.com/book3-thumbs/page-064.jpg Why Do Roofs Have Gutters? A gutter is a rain ditch along the roof edge. It catches falling water, and sends it down a pipe, away from the walls. Let's see how it works! https://socialmedia.xdme.com/tony/videos-book3/page-064.mp4 https://www.youtube.com/embed/EgjFCAUL1hs 117 2026-09-30T03:46:17+00:00 yes https://xdme.com/watch-book3-q065.html https://xdme.com/book3-thumbs/page-065.jpg Why Do Buildings Have Insulation? Insulation is a fluffy or foamy layer that slows down heat. In winter, it keeps warmth in. In summer, it keeps heat out. https://socialmedia.xdme.com/tony/videos-book3/page-065.mp4 https://www.youtube.com/embed/mFGeaOOY6dw 118 2026-09-30T07:10:04+00:00 yes https://xdme.com/watch-book3-q066.html https://xdme.com/book3-thumbs/page-066.jpg Why Can Cranes Lift So Much? A crane is a tall lever with a motor and a counterweight. It trades a long arm for a huge lift! Let's see how a tower crane works. https://socialmedia.xdme.com/tony/videos-book3/page-066.mp4 https://www.youtube.com/embed/nbukvWTxoD8 118 2026-09-30T09:53:07+00:00 yes https://xdme.com/watch-book3-q067.html https://xdme.com/book3-thumbs/page-067.jpg Why Do Dams Hold Back Water? A dam is a giant plug in a river valley. It stores a lake on one side, and lets a controlled trickle out the other. Let's see how dams hold back water! https://socialmedia.xdme.com/tony/videos-book3/page-067.mp4 https://www.youtube.com/embed/LCiPg1GxhJg 118 2026-09-30T04:19:33+00:00 yes https://xdme.com/watch-book3-q068.html https://xdme.com/book3-thumbs/page-068.jpg Why Do Lighthouses Flash? A lighthouse is a coded flashlight for ships. The flash pattern tells sailors which coast they are near, even in fog. Let's see how lighthouses flash! https://socialmedia.xdme.com/tony/videos-book3/page-068.mp4 https://www.youtube.com/embed/wTpc4o1NM1s 118 2026-09-30T04:28:36+00:00 yes https://xdme.com/watch-book3-q069.html https://xdme.com/book3-thumbs/page-069.jpg Why Do Stadiums Have Huge Roofs? A stadium roof is a giant umbrella. It keeps rain, snow, and harsh sun off thousands of seats, without a forest of columns on the field. Let's see how stadiums get roofs! https://socialmedia.xdme.com/tony/videos-book3/page-069.mp4 https://www.youtube.com/embed/pZOVpZPfNPk 119 2026-09-30T10:04:54+00:00 yes https://xdme.com/watch-book3-q070.html https://xdme.com/book3-thumbs/page-070.jpg Why Do Towers Stay Standing? A tower is a tall, skinny building that must fight the wind and its own weight. A wide base and a strong core keep it from tipping. Let's see how towers stay standing! https://socialmedia.xdme.com/tony/videos-book3/page-070.mp4 https://www.youtube.com/embed/P3SuOB9Ndow 118 2026-09-30T06:25:02+00:00 yes https://xdme.com/watch-book3-q071.html https://xdme.com/book3-thumbs/page-071.jpg Why Do Floors Have Beams? Beams are the hidden bones of a floor. They stretch from wall to wall, so the boards you walk on don't sag like a trampoline. Let's see how floor beams work! https://socialmedia.xdme.com/tony/videos-book3/page-071.mp4 https://www.youtube.com/embed/1T9Hk0Q19gg 118 2026-09-30T05:00:19+00:00 yes https://xdme.com/watch-book3-q072.html https://xdme.com/book3-thumbs/page-072.jpg Why Do Cities Have Sewers? A sewer is an underground river that carries dirty water away from homes. That keeps streets and wells clean. Let's follow the water! https://socialmedia.xdme.com/tony/videos-book3/page-072.mp4 https://www.youtube.com/embed/mYRcV7DFzEQ 117 2026-09-30T06:31:33+00:00 yes https://xdme.com/watch-book3-q073.html https://xdme.com/book3-thumbs/page-073.jpg Why Do Sidewalks Crack? Concrete is strong, but it shrinks, swells, and sits on soil that moves. Cracks are the slab's way of relieving that push. So a crack is not always a mistake! https://socialmedia.xdme.com/tony/videos-book3/page-073.mp4 https://www.youtube.com/embed/etMeqFN7pU0 117 2026-09-30T05:19:30+00:00 yes https://xdme.com/watch-book3-q074.html https://xdme.com/book3-thumbs/page-074.jpg Why Do Pyramids Last So Long? A pyramid is a mountain of stone with a very wide base. Most of its weight sits near the ground, so it's hard to tip, and hard to wear away. Let's see why pyramids last so long! https://socialmedia.xdme.com/tony/videos-book3/page-074.mp4 https://www.youtube.com/embed/1v-jSbCi2iI 117 2026-09-30T05:24:34+00:00 yes https://xdme.com/watch-book3-q075.html https://xdme.com/book3-thumbs/page-075.jpg Why Do Buildings Need Doors That Open? Walls keep weather out, but people, air, and furniture must still go in and out. A door is a framed hole in a wall that you can move! Let's see how doors work. https://socialmedia.xdme.com/tony/videos-book3/page-075.mp4 https://www.youtube.com/embed/g3W7xtidbLY 118 2026-09-30T06:43:37+00:00 yes https://xdme.com/watch-book3-q076.html https://xdme.com/book3-thumbs/page-076.jpg Why Do Phones Ring? A ring is a loud "look at me" signal. The network sends a special call-waiting code, and your phone turns that code into sound and vibration. Let's see how phones ring! https://socialmedia.xdme.com/tony/videos-book3/page-076.mp4 https://www.youtube.com/embed/dSEkMvWhVbw 118 2026-09-30T10:15:21+00:00 yes https://xdme.com/watch-book3-q077.html https://xdme.com/book3-thumbs/page-077.jpg Why Does Email Arrive So Fast? Email is a letter that has been chopped into tiny digital packets. Those packets race through cables and radio links at nearly the speed of light! There's no paper, no truck, and n https://socialmedia.xdme.com/tony/videos-book3/page-077.mp4 https://www.youtube.com/embed/c3j_g5VPuAU 121 2026-09-29T21:02:23+00:00 yes https://xdme.com/watch-book3-q078.html https://xdme.com/book3-thumbs/page-078.jpg Why Do Radios Play Music From Far Away? A radio station shakes electric waves into the air, and your radio catches those waves and turns them back into sound. Sound is too weak to travel for miles. But radio waves are a https://socialmedia.xdme.com/tony/videos-book3/page-078.mp4 https://www.youtube.com/embed/2YHpWhy-gWQ 124 2026-09-29T21:02:24+00:00 yes https://xdme.com/watch-book3-q079.html https://xdme.com/book3-thumbs/page-079.jpg Why Do Cameras Take Pictures? A camera is a dark box that traps a pattern of light. A sensor, or long ago a piece of film, remembers that pattern as a picture. A lens bends the incoming light onto a grid of tin https://socialmedia.xdme.com/tony/videos-book3/page-079.mp4 https://www.youtube.com/embed/sXOb72_mEYk 120 2026-09-29T21:02:25+00:00 yes https://xdme.com/watch-book3-q080.html https://xdme.com/book3-thumbs/page-080.jpg Why Do Clocks Keep Time? A clock counts equal little ticks and adds them up into seconds, minutes, and hours. Steady ticks make trustworthy time. That is why a good clock never gets bored of counting! https://socialmedia.xdme.com/tony/videos-book3/page-080.mp4 https://www.youtube.com/embed/zCukLwA8YCc 126 2026-09-29T21:02:26+00:00 yes https://xdme.com/watch-book3-q081.html https://xdme.com/book3-thumbs/page-081.jpg Why Do Computers Need Programs? A program is a list of instructions that a computer follows. Without programs, a computer is just a quiet box of chips. Inside, electricity flips tiny switches called bits on and o https://socialmedia.xdme.com/tony/videos-book3/page-081.mp4 https://www.youtube.com/embed/PPC9l63DKe4 122 2026-09-29T21:02:27+00:00 yes https://xdme.com/watch-book3-q082.html https://xdme.com/book3-thumbs/page-082.jpg Why Does Wi-Fi Have No Wires? Wi-Fi is a short-range radio conversation between your device and a box called a router. Instead of a cable, the air carries the data. The router and your tablet agree on a radio c https://socialmedia.xdme.com/tony/videos-book3/page-082.mp4 https://www.youtube.com/embed/wLuSHyCT2G0 128 2026-09-29T21:02:28+00:00 yes https://xdme.com/watch-book3-q083.html https://xdme.com/book3-thumbs/page-083.jpg Why Do Barcodes Beep at the Store? A barcode is a price tag written in fat and skinny lines. A scanner reads the pattern with light, and looks up the item in a computer. Black lines soak up the scanner's light, and https://socialmedia.xdme.com/tony/videos-book3/page-083.mp4 https://www.youtube.com/embed/jd-UCSF_qUA 120 2026-09-29T21:02:29+00:00 yes https://xdme.com/watch-book3-q084.html https://xdme.com/book3-thumbs/page-084.jpg Why Do TVs Show Moving Pictures? A TV shows lots of still pictures, one after another, so fast that your brain blends them into motion. This is called persistence of vision. Modern screens use millions of tiny col https://socialmedia.xdme.com/tony/videos-book3/page-084.mp4 https://www.youtube.com/embed/KKBDSKE9HmM 121 2026-09-29T21:02:33+00:00 yes https://xdme.com/watch-book3-q085.html https://xdme.com/book3-thumbs/page-085.jpg Why Do Speakers Make Sound? A speaker has a paper or plastic cone that pushes air. And pushing air in a pattern is exactly what sound is! Inside, electricity runs through a coil beside a magnet. https://socialmedia.xdme.com/tony/videos-book3/page-085.mp4 https://www.youtube.com/embed/UHUmrJV-ZbU 123 2026-09-29T21:02:35+00:00 yes https://xdme.com/watch-book3-q086.html https://xdme.com/book3-thumbs/page-086.jpg Why Do Keyboards Have Letters? A keyboard is a map of buttons. Each key tells the computer, this letter, please, so you do not have to draw every character by hand. Under each key is a switch. https://socialmedia.xdme.com/tony/videos-book3/page-086.mp4 https://www.youtube.com/embed/cZxwC1mZubM 115 2026-09-29T21:11:16+00:00 yes https://xdme.com/watch-book3-q087.html https://xdme.com/book3-thumbs/page-087.jpg Why Do Printers Put Ink on Paper? A printer is like a robot painter. It puts tiny dots of ink or powder on paper, following instructions from a computer. Even photos are made of millions of tiny dots that are too s https://socialmedia.xdme.com/tony/videos-book3/page-087.mp4 https://www.youtube.com/embed/fdIO8z4BrK8 119 2026-09-29T21:31:20+00:00 yes https://xdme.com/watch-book3-q088.html https://xdme.com/book3-thumbs/page-088.jpg Why Do Satellites Help Phones? Some phone signals hop up to space! A satellite is like a radio tower that floats high above Earth, and it can see a huge patch of the planet at once. The satellite receives a call https://socialmedia.xdme.com/tony/videos-book3/page-088.mp4 https://www.youtube.com/embed/EMpk6t10PCU 123 2026-09-29T21:51:25+00:00 yes https://xdme.com/watch-book3-q089.html https://xdme.com/book3-thumbs/page-089.jpg Why Does GPS Know Where You Are? Radio beeps take time to travel. So the farther a satellite is, the later its beep arrives. Comparing those delays pins you on the map! https://socialmedia.xdme.com/tony/videos-book3/page-089.mp4 https://www.youtube.com/embed/BqkRUA6_pDo 123 2026-09-29T22:11:01+00:00 yes https://xdme.com/watch-book3-q090.html https://xdme.com/book3-thumbs/page-090.jpg Why Do Traffic Lights Change? A traffic light is a turn-taking machine. It gives each direction a safe slice of time, so cars and walkers do not all move at once. A controller box runs a timer, and sensors in t https://socialmedia.xdme.com/tony/videos-book3/page-090.mp4 https://www.youtube.com/embed/P2nyaM0sCUY 115 2026-09-29T22:31:35+00:00 yes https://xdme.com/watch-book3-q091.html https://xdme.com/book3-thumbs/page-091.jpg Why Do Doorbells Ring? A doorbell is a tiny messenger. When you press the button, it closes a circuit, and electricity flows to a chime or a phone to announce a visitor. Old doorbells used a magnet to ta https://socialmedia.xdme.com/tony/videos-book3/page-091.mp4 https://www.youtube.com/embed/2AR0qVkyPFM 120 2026-09-29T22:52:11+00:00 yes https://xdme.com/watch-book3-q092.html https://xdme.com/book3-thumbs/page-092.jpg Why Did Morse Code Use Dots and Dashes? Morse code turns letters into short beeps, called dots, and long beeps, called dashes, so messages can travel over a wire or in flashes of light. Electricity on a wire is either on https://socialmedia.xdme.com/tony/videos-book3/page-092.mp4 https://www.youtube.com/embed/4SsxKPxu3Sg 119 2026-09-29T23:11:45+00:00 yes https://xdme.com/watch-book3-q093.html https://xdme.com/book3-thumbs/page-093.jpg Why Do QR Codes Hold So Much? A camera reads the pattern like a map. Three big finder squares in the corners tell the phone which way is up. Then software turns the grid back into letters or numbers. https://socialmedia.xdme.com/tony/videos-book3/page-093.mp4 https://www.youtube.com/embed/uSg2WNGpnWU 122 2026-09-29T23:32:21+00:00 yes https://xdme.com/watch-book3-q094.html https://xdme.com/book3-thumbs/page-094.jpg Why Do Microphones Pick Up Voices? A microphone is like an ear made of parts. Sound is just shaking air, and the mic turns those shakes into a tiny electric wiggle. Your phone mic is smaller than a pea, yet it can t https://socialmedia.xdme.com/tony/videos-book3/page-094.mp4 https://www.youtube.com/embed/WXxhEER0Vis 124 2026-09-29T23:52:26+00:00 yes https://xdme.com/watch-book3-q095.html https://xdme.com/book3-thumbs/page-095.jpg Why Do Headphones Work? Headphones are tiny speakers. They take an electric signal and shake a small disc to turn it back into sound. Over-ear cups seal out noise, while earbuds sit closer to your eardrum https://socialmedia.xdme.com/tony/videos-book3/page-095.mp4 https://www.youtube.com/embed/6pZfhUH1sVc 118 2026-09-30T00:12:40+00:00 yes https://xdme.com/watch-book3-q096.html https://xdme.com/book3-thumbs/page-096.jpg Why Do Video Calls Show Faces Far Away? A video call is a conversation made of pictures and sound, chopped into tiny packets that race through the internet. A camera snaps many still pictures. Software squeezes them into https://socialmedia.xdme.com/tony/videos-book3/page-096.mp4 https://www.youtube.com/embed/kOYvFm9IWYs 121 2026-09-30T00:33:25+00:00 yes https://xdme.com/watch-book3-q097.html https://xdme.com/book3-thumbs/page-097.jpg Why Do Robots Follow Instructions? A robot is a machine with sensors, motors, and a computer that works like a brain. It only follows its program's list of steps, unless a human changes that list. Code is like a rec https://socialmedia.xdme.com/tony/videos-book3/page-097.mp4 https://www.youtube.com/embed/Y5Mg8w3gti0 123 2026-09-30T00:48:58+00:00 yes https://xdme.com/watch-book3-q098.html https://xdme.com/book3-thumbs/page-098.jpg Why Do Remote Controls Work? Inside, a chip turns your finger press into a pattern of on-and-off pulses, and the TV's sensor listens for that pattern. The same idea works for garage doors, drones, ceiling fans https://socialmedia.xdme.com/tony/videos-book3/page-098.mp4 https://www.youtube.com/embed/hXFnksZ425M 119 2026-09-30T01:02:33+00:00 yes https://xdme.com/watch-book3-q099.html https://xdme.com/book3-thumbs/page-099.jpg Why Do Smoke Alarms Beep? A smoke alarm is a tiny lookout. It watches the air in a room, and shouts a loud beep if smoke particles show that a fire may have started. Many alarms shine a small light across a https://socialmedia.xdme.com/tony/videos-book3/page-099.mp4 https://www.youtube.com/embed/us8ubGevyZA 123 2026-09-30T01:16:07+00:00 yes https://xdme.com/watch-book3-q100.html https://xdme.com/book3-thumbs/page-100.jpg Why Do Passwords Exist? A password is a secret key made of letters, numbers, or a pattern. It proves that you are you, so a phone, game, or door will open only for the right person. The device stores a lo https://socialmedia.xdme.com/tony/videos-book3/page-100.mp4 https://www.youtube.com/embed/CyU-dqZj3tw 130 2026-09-30T05:04:20+00:00 yes https://xdme.com/watch-book3-q101.html https://xdme.com/book3-thumbs/page-101.jpg Why Does a Ball Bounce? A bounce is stored squash. When a ball hits the ground, it flattens a little, and the air and rubber inside push it back into a round shape. That push launches the ball upward! https://socialmedia.xdme.com/tony/videos-book3/page-101.mp4 https://www.youtube.com/embed/jp98i0K10EI 118 2026-09-30T02:15:36+00:00 yes https://xdme.com/watch-book3-q102.html https://xdme.com/book3-thumbs/page-102.jpg Why Can You Ride a Bike Without Falling? If the bike tips left, the front wheel turns left, and the wheels curve back under your weight. Balance is harder at slow speeds, because that steering help is weaker. https://socialmedia.xdme.com/tony/videos-book3/page-102.mp4 https://www.youtube.com/embed/-37RH13ip0I 120 2026-09-30T03:50:50+00:00 yes https://xdme.com/watch-book3-q103.html https://xdme.com/book3-thumbs/page-103.jpg Why Do Swim Goggles Keep Water Out? Goggles are like dry rooms for your eyes. A soft gasket makes a seal against your skin, and a strap holds it tight. A good seal plus a small pocket of air keeps the pressure even, https://socialmedia.xdme.com/tony/videos-book3/page-103.mp4 https://www.youtube.com/embed/39PewIzL00k 116 2026-09-30T02:25:39+00:00 yes https://xdme.com/watch-book3-q104.html https://xdme.com/book3-thumbs/page-104.jpg Why Does a Bat Have a Sweet Spot? The sweet spot is the place on the barrel where the bat springs forward with the least sting in your hands. Hit there, and more energy goes into the ball. A bat is a lever that als https://socialmedia.xdme.com/tony/videos-book3/page-104.mp4 https://www.youtube.com/embed/-jF6SYWZHHs 115 2026-09-30T02:30:40+00:00 yes https://xdme.com/watch-book3-q105.html https://xdme.com/book3-thumbs/page-105.jpg Why Is a Soccer Ball Made of Panels? A soccer ball is a round puzzle. Flat panels, sewn or glued together, curve into a sphere that holds air and rolls true. Basketballs and volleyballs use panels too! https://socialmedia.xdme.com/tony/videos-book3/page-105.mp4 https://www.youtube.com/embed/5y1qqYzwNp0 123 2026-09-30T05:14:28+00:00 yes https://xdme.com/watch-book3-q106.html https://xdme.com/book3-thumbs/page-106.jpg Why Does a Whistle Get So Loud? A whistle is a tiny wind instrument. Your breath slams into a sharp edge and a small chamber, which chops the air into fast pulses that your ears hear as a piercing tone. In some w https://socialmedia.xdme.com/tony/videos-book3/page-106.mp4 https://www.youtube.com/embed/V-atHfxjgW4 119 2026-09-30T02:38:11+00:00 yes https://xdme.com/watch-book3-q107.html https://xdme.com/book3-thumbs/page-107.jpg Why Do Drums Boom? A drum is a stretched skin, or plastic head, over a hollow body. A hit makes the head bounce, and that bounce shoves a big gulp of air into a booming sound wave. A larger head move https://socialmedia.xdme.com/tony/videos-book3/page-107.mp4 https://www.youtube.com/embed/HlazipTPMmU 120 2026-09-30T04:43:13+00:00 yes https://xdme.com/watch-book3-q108.html https://xdme.com/book3-thumbs/page-108.jpg Why Does Tightening a Guitar String Raise the Pitch? Pitch depends on how fast something vibrates. A tighter string, just like a tighter rubber band, snaps back faster and makes a higher note. Three things set a string's note: how ti https://socialmedia.xdme.com/tony/videos-book3/page-108.mp4 https://www.youtube.com/embed/8f2iaghpf0M 117 2026-09-30T02:46:44+00:00 yes https://xdme.com/watch-book3-q109.html https://xdme.com/book3-thumbs/page-109.jpg Why Does an Echo Come Back? An echo is a sound's return trip. Sound is a wave in the air, and a hard wall can bounce the wave back, a little bit late, so you hear yourself twice. Soft things like couches soak https://socialmedia.xdme.com/tony/videos-book3/page-109.mp4 https://www.youtube.com/embed/pOIeMW4RSXo 116 2026-09-30T02:54:30+00:00 yes https://xdme.com/watch-book3-q110.html https://xdme.com/book3-thumbs/page-110.jpg Why Do Ice Skates Glide? A skate blade is a thin metal edge that puts your weight on a tiny line of ice. Pressure plus a slick, water-like layer on the ice lets the blade slide instead of stick. Ice is alr https://socialmedia.xdme.com/tony/videos-book3/page-110.mp4 https://www.youtube.com/embed/AnCjSZ3D1yw 120 2026-09-30T03:03:32+00:00 yes https://xdme.com/watch-book3-q111.html https://xdme.com/book3-thumbs/page-111.jpg Why Does a Frisbee Fly? A flying disc is a spinning wing. Air moves faster over the curved top than under the rim, and that creates lift. Tilt the disc, and it curves! https://socialmedia.xdme.com/tony/videos-book3/page-111.mp4 https://www.youtube.com/embed/jZfuWlXedUY 121 2026-09-30T03:09:04+00:00 yes https://xdme.com/watch-book3-q112.html https://xdme.com/book3-thumbs/page-112.jpg Why Does a Swing Go Higher If You Pump? Pumping is a timing trick. By moving your body at the right moments, you add a little push on every pass, and the arc grows. Lean back and kick your legs out as you swing forward, https://socialmedia.xdme.com/tony/videos-book3/page-112.mp4 https://www.youtube.com/embed/y2CFa75hR0A 117 2026-09-30T03:20:08+00:00 yes https://xdme.com/watch-book3-q113.html https://xdme.com/book3-thumbs/page-113.jpg Why Do Helmets Have Foam? A helmet is a crash sandwich. A hard shell spreads out a hit, and thick foam crushes on purpose, so your head slows down more gently. Sudden stops hurt. https://socialmedia.xdme.com/tony/videos-book3/page-113.mp4 https://www.youtube.com/embed/Mljy2X0RS6o 118 2026-09-30T04:56:47+00:00 yes https://xdme.com/watch-book3-q114.html https://xdme.com/book3-thumbs/page-114.jpg Why Does a Yo-Yo Come Back? A yo-yo doesn't come back by magic. It comes back because of stored-up spin! The string wraps around a little rod called an axle, and the spinning discs can wind that string right https://socialmedia.xdme.com/tony/videos-book3/page-114.mp4 https://www.youtube.com/embed/fdrL59EICzE 125 2026-09-29T21:02:36+00:00 yes https://xdme.com/watch-book3-q115.html https://xdme.com/book3-thumbs/page-115.jpg Why Do Bubbles Shimmer Then Pop? A bubble is a super thin sandwich of water and soap, with air inside. Light bounces off that thin skin and mixes into rainbow colors, until the wall gets too thin and breaks! https://socialmedia.xdme.com/tony/videos-book3/page-115.mp4 https://www.youtube.com/embed/zTV0fNglzT4 129 2026-09-29T21:02:47+00:00 yes https://xdme.com/watch-book3-q116.html https://xdme.com/book3-thumbs/page-116.jpg Why Does a Kite Need Wind? A kite is like a wing on a string. Moving air hits its tilted face and slides over the top. The difference in push lifts the kite up, against gravity! https://socialmedia.xdme.com/tony/videos-book3/page-116.mp4 https://www.youtube.com/embed/0Kob64kAE4E 122 2026-09-29T21:02:56+00:00 yes https://xdme.com/watch-book3-q117.html https://xdme.com/book3-thumbs/page-117.jpg Why Do Sneakers Grip the Ground? Sneaker soles are made of patterned rubber. The pattern bites into tiny hills on the ground. The soft rubber also flexes, so more of the shoe actually touches. https://socialmedia.xdme.com/tony/videos-book3/page-117.mp4 https://www.youtube.com/embed/IGEiwRXrm94 122 2026-09-29T21:03:05+00:00 yes https://xdme.com/watch-book3-q118.html https://xdme.com/book3-thumbs/page-118.jpg Why Does a Jump Rope Need a Rhythm? A jump rope is a turning loop. Your feet have to leave the ground in the tiny window when the rope is down. Then you land before it comes around again. https://socialmedia.xdme.com/tony/videos-book3/page-118.mp4 https://www.youtube.com/embed/uIr-B4vneMM 121 2026-09-29T21:03:09+00:00 yes https://xdme.com/watch-book3-q119.html https://xdme.com/book3-thumbs/page-119.jpg Why Do Bowling Balls Have Finger Holes? Finger holes are like handles cut right into a heavy ball. They let you lift, swing, and let go of the ball, without dropping it on your foot! https://socialmedia.xdme.com/tony/videos-book3/page-119.mp4 https://www.youtube.com/embed/kAc6c2M-bRI 119 2026-09-29T21:03:11+00:00 yes https://xdme.com/watch-book3-q120.html https://xdme.com/book3-thumbs/page-120.jpg Why Does a Basketball Have Black Lines? Those black lines are little channels between the panels. They give your fingers a ridge to push against, so a pass or shot doesn't slip off the smooth orange ball. https://socialmedia.xdme.com/tony/videos-book3/page-120.mp4 https://www.youtube.com/embed/hnsl2W-DenM 123 2026-09-29T21:03:15+00:00 yes https://xdme.com/watch-book3-q121.html https://xdme.com/book3-thumbs/page-121.jpg Why Do Referees Use Whistles? A whistle is like a tiny, super loud speaker. Its sharp blast cuts through crowd noise. So every player hears the same stop or start signal, at the very same instant! https://socialmedia.xdme.com/tony/videos-book3/page-121.mp4 https://www.youtube.com/embed/lo3qAsbJPJY 121 2026-09-29T21:11:17+00:00 yes https://xdme.com/watch-book3-q122.html https://xdme.com/book3-thumbs/page-122.jpg Why Does a Trombone Note Drop When the Slide Moves Out? A trombone is a long sliding tube. When the slide goes out, the column of air inside gets longer. A longer column vibrates more slowly, so the pitch falls! https://socialmedia.xdme.com/tony/videos-book3/page-122.mp4 https://www.youtube.com/embed/cAEKzoFdAPs 114 2026-09-29T21:31:21+00:00 yes https://xdme.com/watch-book3-q123.html https://xdme.com/book3-thumbs/page-123.jpg Why Do Marching Bands Stay in Step? Staying in step is all about shared timing. A drum cadence gives every player the same beat. So dozens of feet land together, instead of turning into a shuffle! https://socialmedia.xdme.com/tony/videos-book3/page-123.mp4 https://www.youtube.com/embed/i8M10L3Fa2o 118 2026-09-29T21:50:55+00:00 yes https://xdme.com/watch-book3-q124.html https://xdme.com/book3-thumbs/page-124.jpg Why Does a Playground Slide Feel Fast? A slide trades height for speed. Gravity pulls you down the slope. And a smooth surface steals less speed from friction, so you arrive at the bottom in a rush! https://socialmedia.xdme.com/tony/videos-book3/page-124.mp4 https://www.youtube.com/embed/MkF0741Pkxg 118 2026-09-29T22:10:30+00:00 yes https://xdme.com/watch-book3-q125.html https://xdme.com/book3-thumbs/page-125.jpg Why Do Team Jerseys Have Numbers? A number is a name you can read from the bleachers. Faces blur at midfield, but a giant 12 on the back stays clear. So fans, referees, and cameras can tell the players apart! https://socialmedia.xdme.com/tony/videos-book3/page-125.mp4 https://www.youtube.com/embed/sZMCcMwCAwQ 126 2026-09-29T22:31:36+00:00 yes https://xdme.com/watch-book3-q126.html https://xdme.com/book3-thumbs/page-126.jpg Why Does a Hammer Have a Heavy Head? A hammer is like a small energy pack. A heavy head at the end of a handle stores motion. Then it dumps that motion into one tiny spot on a nail! https://socialmedia.xdme.com/tony/videos-book3/page-126.mp4 https://www.youtube.com/embed/q9bTM8chpCk 119 2026-09-29T22:50:40+00:00 yes https://xdme.com/watch-book3-q127.html https://xdme.com/book3-thumbs/page-127.jpg Why Is a Screwdriver Shaped Like That? A screwdriver is a twist messenger. The handle fits your hand, and the shaft carries the turn. And the tip matches the screw, so the turn doesn't slip! https://socialmedia.xdme.com/tony/videos-book3/page-127.mp4 https://www.youtube.com/embed/45S9m4jOKEE 123 2026-09-29T23:12:15+00:00 yes https://xdme.com/watch-book3-q128.html https://xdme.com/book3-thumbs/page-128.jpg Why Do Scissors Have Two Blades? Scissors are two knives that meet. One blade holds the paper, and the other blade slides past it. The pinch between them shears the paper, instead of tearing it! https://socialmedia.xdme.com/tony/videos-book3/page-128.mp4 https://www.youtube.com/embed/PbSyaE6_i2I 127 2026-09-29T23:31:20+00:00 yes https://xdme.com/watch-book3-q129.html https://xdme.com/book3-thumbs/page-129.jpg Why Does Glue Stick? Glue is a liquid bridge that turns solid. It wets both surfaces and seeps into tiny pores. Then it hardens, so the two things share one skin! https://socialmedia.xdme.com/tony/videos-book3/page-129.mp4 https://www.youtube.com/embed/Kh796yRv46A 125 2026-09-29T23:52:27+00:00 yes https://xdme.com/watch-book3-q130.html https://xdme.com/book3-thumbs/page-130.jpg Why Does Tape Have Two Sides That Feel Different? Tape is a sandwich. One side is a smooth backing made of plastic or paper. The other side is a thin coat of sticky stuff called adhesive! https://socialmedia.xdme.com/tony/videos-book3/page-130.mp4 https://www.youtube.com/embed/oMbq5I0tuCM 127 2026-09-30T00:12:49+00:00 yes https://xdme.com/watch-book3-q131.html https://xdme.com/book3-thumbs/page-131.jpg Why Do Nails Have Points and Screws Have Threads? A nail is a wedge that you tap. A screw is a ramp that you twist. Both hold wood together, but they grab in different ways! https://socialmedia.xdme.com/tony/videos-book3/page-131.mp4 https://www.youtube.com/embed/jy71eRodTRg 118 2026-09-30T00:32:24+00:00 yes https://xdme.com/watch-book3-q132.html https://xdme.com/book3-thumbs/page-132.jpg Why Does Sandpaper Scratch? Sandpaper is a crowd of tiny hard teeth, glued onto paper or cloth. Each tooth plows a microscopic groove and carries away a speck of wood or paint! https://socialmedia.xdme.com/tony/videos-book3/page-132.mp4 https://www.youtube.com/embed/zYuzhxGXbnU 125 2026-09-30T00:48:59+00:00 yes https://xdme.com/watch-book3-q133.html https://xdme.com/book3-thumbs/page-133.jpg Why Does a Measuring Tape Roll Back Up? Inside the case, there's a spring. You store energy when you pull the tape out. Then when you let go, that spring winds the tape back home! https://socialmedia.xdme.com/tony/videos-book3/page-133.mp4 https://www.youtube.com/embed/t6Bqc5b19oU 119 2026-09-30T01:02:02+00:00 yes https://xdme.com/watch-book3-q134.html https://xdme.com/book3-thumbs/page-134.jpg Why Do Magnets Pick Up Only Some Metals? A magnet has an invisible field around it. Some metals have tiny mini-magnets inside that can line up with that field. Those metals jump to the magnet. https://socialmedia.xdme.com/tony/videos-book3/page-134.mp4 https://www.youtube.com/embed/c3KJfKuZ6WE 126 2026-09-30T01:16:08+00:00 yes https://xdme.com/watch-book3-q135.html https://xdme.com/book3-thumbs/page-135.jpg Why Does a Level Have a Bubble? The bubble is a leftover air pocket, floating in a slightly curved vial of liquid. Gravity pulls the liquid down, so the bubble always drifts to the highest point! https://socialmedia.xdme.com/tony/videos-book3/page-135.mp4 https://www.youtube.com/embed/7-x_ASZVd9A 123 2026-09-30T03:31:12+00:00 yes https://xdme.com/watch-book3-q136.html https://xdme.com/book3-thumbs/page-136.jpg Why Do Factories Use Conveyor Belts? A conveyor belt is like a moving sidewalk for stuff. Motors turn rollers, and the belt slides along. So parts travel to the next job, without each worker carrying every box! https://socialmedia.xdme.com/tony/videos-book3/page-136.mp4 https://www.youtube.com/embed/gNVTfaHNSGI 129 2026-09-30T08:04:49+00:00 yes https://xdme.com/watch-book3-q137.html https://xdme.com/book3-thumbs/page-137.jpg Why Do Bakers Weigh Instead of Just Scoop? A scoop measures space, but a scale measures mass. Flour packed tight in a cup is more flour than fluffy flour. So weighing keeps a recipe honest! https://socialmedia.xdme.com/tony/videos-book3/page-137.mp4 https://www.youtube.com/embed/A-_EKBxgUJg 126 2026-09-30T08:29:47+00:00 yes https://xdme.com/watch-book3-q138.html https://xdme.com/book3-thumbs/page-138.jpg Why Does a Sewing Machine Make a Lockstitch? A lockstitch uses two threads that loop through each other, inside the fabric. Neither thread can pull out easily, because each one holds the other! https://socialmedia.xdme.com/tony/videos-book3/page-138.mp4 https://www.youtube.com/embed/Fn-7qBQejgY 127 2026-09-30T09:00:14+00:00 yes https://xdme.com/watch-book3-q139.html https://xdme.com/book3-thumbs/page-139.jpg Why Do 3D Printers Print in Layers? A 3D printer can't just poof a whole toy into the air. It draws one thin slice, waits for it to set, and then draws the next slice on top. Layer by layer, a shape grows! https://socialmedia.xdme.com/tony/videos-book3/page-139.mp4 https://www.youtube.com/embed/odEwLlQ1kd0 130 2026-09-30T04:15:30+00:00 yes https://xdme.com/watch-book3-q140.html https://xdme.com/book3-thumbs/page-140.jpg Why Do Welders Wear a Dark Mask? Welding light is brighter and harsher than a lamp. A dark mask is like a filter that blocks the extra brightness. It also blocks invisible rays that can burn eyes and skin! https://socialmedia.xdme.com/tony/videos-book3/page-140.mp4 https://www.youtube.com/embed/IH-8hfBcJW0 125 2026-09-30T04:23:34+00:00 yes https://xdme.com/watch-book3-q141.html https://xdme.com/book3-thumbs/page-141.jpg Why Does a Potter's Wheel Spin? A spinning wheel turns lumps of clay into even walls. Every side of the pot meets your hands at the same speed. So the shape stays round! https://socialmedia.xdme.com/tony/videos-book3/page-141.mp4 https://www.youtube.com/embed/IIU790hSDh4 128 2026-09-30T09:48:01+00:00 yes https://xdme.com/watch-book3-q142.html https://xdme.com/book3-thumbs/page-142.jpg Why Do Carpenters Use Squares? A square is a frozen right angle. It checks that two edges meet at 90 degrees. So walls stand straight, and frames don't lean over into slanted shapes! https://socialmedia.xdme.com/tony/videos-book3/page-142.mp4 https://www.youtube.com/embed/fwCVMEyfHG4 123 2026-09-30T04:38:41+00:00 yes https://xdme.com/watch-book3-q143.html https://xdme.com/book3-thumbs/page-143.jpg Why Does Paint Dry? Wet paint is bits of color floating in a liquid. Drying means that liquid leaves or changes. Then the color bits lock together into a thin, solid film! https://socialmedia.xdme.com/tony/videos-book3/page-143.mp4 https://www.youtube.com/embed/y0D8EIAkx6k 126 2026-09-30T10:16:52+00:00 yes https://xdme.com/watch-book3-q144.html https://xdme.com/book3-thumbs/page-144.jpg Why Do Zippers Zip? A zipper is two toothy rails and a little slider. The slider is a Y-shaped tunnel. It meshes the teeth together on the way up, and unmeshes them on the way down! https://socialmedia.xdme.com/tony/videos-book3/page-144.mp4 https://www.youtube.com/embed/_NmqU2bmVdk 124 2026-09-30T04:56:48+00:00 yes https://xdme.com/watch-book3-q145.html https://xdme.com/book3-thumbs/page-145.jpg Why Does a Vacuum Cleaner Suck? A vacuum cleaner doesn't really drink up dirt. A fan pushes air out of the machine, so outside air rushes in. And the crumbs ride that incoming wind! https://socialmedia.xdme.com/tony/videos-book3/page-145.mp4 https://www.youtube.com/embed/j2aIix4FlqE 124 2026-09-30T05:09:56+00:00 yes https://xdme.com/watch-book3-q146.html https://xdme.com/book3-thumbs/page-146.jpg Why Do Firefighters Use Axes and Hoses? A fire needs fuel, heat, and air. A hose steals heat with water, and an axe makes a path. So people and water can reach the right spot! https://socialmedia.xdme.com/tony/videos-book3/page-146.mp4 https://www.youtube.com/embed/ZUe6f1aGVOg 125 2026-09-30T05:19:31+00:00 yes https://xdme.com/watch-book3-q147.html https://xdme.com/book3-thumbs/page-147.jpg Why Do Doctors Wear Gloves? Gloves are a thin wall. They keep a doctor's skin from sharing tiny germs with a patient. And they keep a patient's germs off the doctor, too! https://socialmedia.xdme.com/tony/videos-book3/page-147.mp4 https://www.youtube.com/embed/HEVU-c-QumM 122 2026-09-30T10:51:20+00:00 yes https://xdme.com/watch-book3-q148.html https://xdme.com/book3-thumbs/page-148.jpg Why Does a Cash Register Beep? The beep is a confirmation sound. It means a scan or key press worked. So the machine sings one short note, instead of making the cashier look down every time! https://socialmedia.xdme.com/tony/videos-book3/page-148.mp4 https://www.youtube.com/embed/BB0jeEPjNtM 123 2026-09-30T06:57:22+00:00 yes https://xdme.com/watch-book3-q149.html https://xdme.com/book3-thumbs/page-149.jpg Why Do Libraries Use the Same Number Codes? Shared numbers are like a map. If sharks are 597 in one town, they can be 597 in the next town too. So any library feels a little like home! https://socialmedia.xdme.com/tony/videos-book3/page-149.mp4 https://www.youtube.com/embed/a0jW9dFKoZo 129 2026-09-30T11:30:23+00:00 yes https://xdme.com/watch-book3-q150.html https://xdme.com/book3-thumbs/page-150.jpg Why Do Makers Prototype First? A prototype is a practice version. It's cheap, fast, and allowed to fail. So the real thing can succeed! https://socialmedia.xdme.com/tony/videos-book3/page-150.mp4 https://www.youtube.com/embed/EcizZxDkfCk 127 2026-09-30T07:27:16+00:00 yes https://xdme.com/watch-book4-q001.html https://xdme.com/book4-thumbs/page-001.jpg Why Are Leaves Green? Leaves look green because they are packed with chlorophyll, a green tool. Chlorophyll catches sunlight, and that helps the plant make its own food. So the green color is a clue tha https://socialmedia.xdme.com/tony/videos-book4/page-001.mp4 https://www.youtube.com/embed/SAACgMY6Uhk 120 2026-09-30T23:13:36+00:00 yes https://xdme.com/watch-book4-q002.html https://xdme.com/book4-thumbs/page-002.jpg Why Do Trees Have Bark? Bark is a tree's coat and shield. It keeps out bugs, weather, and bumps that could hurt the soft parts inside. Think of it like a raincoat and a helmet, all wrapped around the trun https://socialmedia.xdme.com/tony/videos-book4/page-002.mp4 https://www.youtube.com/embed/kI7zSehVIgk 120 2026-09-30T23:56:25+00:00 yes https://xdme.com/watch-book4-q003.html https://xdme.com/book4-thumbs/page-003.jpg Why Do Flowers Smell Sweet? A sweet smell is like a billboard for a flower. It tells bees, butterflies, and other helpers that nectar and pollen are here. So flowers smell sweet to get visitors! https://socialmedia.xdme.com/tony/videos-book4/page-003.mp4 https://www.youtube.com/embed/t7-BiOH7TiE 122 2026-10-01T00:54:07+00:00 yes https://xdme.com/watch-book4-q004.html https://xdme.com/book4-thumbs/page-004.jpg Why Do Some Trees Lose Their Leaves? Many trees drop their leaves before winter. That way they do not spend energy on parts that would freeze or dry out when the sun is weak. Let's watch how a leaf lets go! https://socialmedia.xdme.com/tony/videos-book4/page-004.mp4 https://www.youtube.com/embed/KMchxKsUJns 116 2026-10-01T02:08:58+00:00 yes https://xdme.com/watch-book4-q005.html https://xdme.com/book4-thumbs/page-005.jpg Why Do Roots Grow Down? Roots grow down because they follow gravity. Down is where soil holds moisture, and where a plant can anchor itself. So wind does not tip it over! https://socialmedia.xdme.com/tony/videos-book4/page-005.mp4 https://www.youtube.com/embed/uUxWTUdu29I 118 2026-10-01T02:24:00+00:00 yes https://xdme.com/watch-book4-q006.html https://xdme.com/book4-thumbs/page-006.jpg Why Do Plants Need Sunlight? Sunlight is a plant's power source. Without it, chlorophyll cannot make sugar, and the plant slowly runs out of food. So plants lean toward the light! https://socialmedia.xdme.com/tony/videos-book4/page-006.mp4 https://www.youtube.com/embed/1CEp-5s21tY 127 2026-10-01T02:38:37+00:00 yes https://xdme.com/watch-book4-q007.html https://xdme.com/book4-thumbs/page-007.jpg Why Do Seeds Travel? A seed that falls only at its parent's feet must compete with the big plant for light and water. Traveling gives the baby plant a new patch of soil. So seeds have clever ways to go https://socialmedia.xdme.com/tony/videos-book4/page-007.mp4 https://www.youtube.com/embed/UNn7M7Ae8Q0 117 2026-10-01T02:44:39+00:00 yes https://xdme.com/watch-book4-q008.html https://xdme.com/book4-thumbs/page-008.jpg Why Is a Forest Quiet, Then Loud? A forest is full of living sound-makers that clock in at different hours. Midday can feel hushed, while dawn and dusk can roar with birds, frogs, and insects. So the forest is quie https://socialmedia.xdme.com/tony/videos-book4/page-008.mp4 https://www.youtube.com/embed/W7CJBCKxJJg 124 2026-10-01T02:57:35+00:00 yes https://xdme.com/watch-book4-q009.html https://xdme.com/book4-thumbs/page-009.jpg Why Do Mushrooms Pop Up After Rain? The mushroom you see is only the fruit of a fungus. The real fungus is a hidden web in the soil. Rain tells that web that it is time to send up a cap and spread spores! https://socialmedia.xdme.com/tony/videos-book4/page-009.mp4 https://www.youtube.com/embed/18yz-JPmrko 124 2026-10-01T03:05:09+00:00 yes https://xdme.com/watch-book4-q010.html https://xdme.com/book4-thumbs/page-010.jpg Why Do Vines Climb? A vine is a plant that borrows height. Climbing is cheaper than growing a thick trunk, and height means more sunlight. So vines climb to reach the light! https://socialmedia.xdme.com/tony/videos-book4/page-010.mp4 https://www.youtube.com/embed/kEQR3fIcXNA 122 2026-10-01T03:16:18+00:00 yes https://xdme.com/watch-book4-q011.html https://xdme.com/book4-thumbs/page-011.jpg Why Is Moss So Soft and Low? Moss is a tiny plant with no true tall stem and no thick roots. It hugs rock and soil like a soft green cushion. Staying low keeps it in the damp layer near the ground. https://socialmedia.xdme.com/tony/videos-book4/page-011.mp4 https://www.youtube.com/embed/4o7AjREy6_4 117 2026-10-01T03:37:28+00:00 yes https://xdme.com/watch-book4-q012.html https://xdme.com/book4-thumbs/page-012.jpg Why Do Pine Trees Stay Green All Year? Pine needles are leaves built for winter. They are thin, tough, and waxy, so they can keep making a little food even when other trees are bare. That is why pines stay green! https://socialmedia.xdme.com/tony/videos-book4/page-012.mp4 https://www.youtube.com/embed/Zlv1TRBbTXE 121 2026-10-01T03:47:16+00:00 yes https://xdme.com/watch-book4-q013.html https://xdme.com/book4-thumbs/page-013.jpg Why Do Some Plants Have Thorns? Thorns, spines, and prickles are plant armor. They turn a juicy stem or leaf into a painful snack, so many animals try a different plant. Armor is a smart idea when you cannot run https://socialmedia.xdme.com/tony/videos-book4/page-013.mp4 https://www.youtube.com/embed/UN17bnMBckA 119 2026-10-01T04:05:27+00:00 yes https://xdme.com/watch-book4-q014.html https://xdme.com/book4-thumbs/page-014.jpg Why Do Leaves Turn Red and Gold? In autumn, green chlorophyll fades first. Yellow and orange were hiding underneath the whole time. Some trees also make extra red! https://socialmedia.xdme.com/tony/videos-book4/page-014.mp4 https://www.youtube.com/embed/J610Vs8zBQc 124 2026-10-01T04:13:56+00:00 yes https://xdme.com/watch-book4-q015.html https://xdme.com/book4-thumbs/page-015.jpg Why Do Trees Have Rings Inside? A ring is one year of new wood. In many climates, a tree grows in a yearly pulse, so you can count the pulses. The trunk keeps a weather diary inside! https://socialmedia.xdme.com/tony/videos-book4/page-015.mp4 https://www.youtube.com/embed/HjZVkNpBYvQ 117 2026-10-01T04:27:39+00:00 yes https://xdme.com/watch-book4-q016.html https://xdme.com/book4-thumbs/page-016.jpg Why Do Plants Drink Through Roots? Roots are the plant's drinking straws. Tiny hairs pull water and minerals from the soil, so the leaves can cook food in the sun. Let's follow one drink! https://socialmedia.xdme.com/tony/videos-book4/page-016.mp4 https://www.youtube.com/embed/z70vk_kmjsA 118 2026-10-01T04:44:57+00:00 yes https://xdme.com/watch-book4-q017.html https://xdme.com/book4-thumbs/page-017.jpg Why Do Some Flowers Close at Night? Closing is a nightly shield. Petals fold to protect pollen from dew and cold, and from night visitors the flower does not need. It is not sleeping, it is a timed job! https://socialmedia.xdme.com/tony/videos-book4/page-017.mp4 https://www.youtube.com/embed/MY-_Vw_WroE 123 2026-10-01T05:02:49+00:00 yes https://xdme.com/watch-book4-q018.html https://xdme.com/book4-thumbs/page-018.jpg Why Do Weeds Grow in Sidewalk Cracks? A crack is a tiny garden. Wind drops a seed, dust and rain collect, and the seedling only needs a sliver of soil and a strip of sun. Many weeds make thousands of tough seeds! https://socialmedia.xdme.com/tony/videos-book4/page-018.mp4 https://www.youtube.com/embed/BAMFfOOCa34 120 2026-10-01T05:13:40+00:00 yes https://xdme.com/watch-book4-q019.html https://xdme.com/book4-thumbs/page-019.jpg Why Do Forests Feel Cooler? A forest is living shade, plus living air conditioning. Leaves block the sun, and they release water vapor that carries heat away. So the air under the trees feels cooler. https://socialmedia.xdme.com/tony/videos-book4/page-019.mp4 https://www.youtube.com/embed/-ih8otggItI 124 2026-10-01T05:20:44+00:00 yes https://xdme.com/watch-book4-q020.html https://xdme.com/book4-thumbs/page-020.jpg Why Do Acorns Become Oaks? An acorn is an oak baby, packed with lunch. If it lands in damp soil and does not get eaten, that lunch fuels a root, then a shoot, then a tree. That is how a mighty oak begins! https://socialmedia.xdme.com/tony/videos-book4/page-020.mp4 https://www.youtube.com/embed/BeValqCYUok 118 2026-10-01T05:29:28+00:00 yes https://xdme.com/watch-book4-q021.html https://xdme.com/book4-thumbs/page-021.jpg Why Do Some Plants Eat Bugs? A few plants live in soggy soil that lacks minerals. Catching a bug is how they grab extra nutrients, especially nitrogen. The plant still makes its sugar from sunlight. https://socialmedia.xdme.com/tony/videos-book4/page-021.mp4 https://www.youtube.com/embed/cyz0zuoty_I 126 2026-10-01T05:38:04+00:00 yes https://xdme.com/watch-book4-q022.html https://xdme.com/book4-thumbs/page-022.jpg Why Do Cactuses Store Water? A desert can go weeks without rain. A cactus is a living water tank, with a waxy skin that slows leaks and thick stems that hold moisture. Deserts are very dry, so every drop count https://socialmedia.xdme.com/tony/videos-book4/page-022.mp4 https://www.youtube.com/embed/2MKdednxtUg 120 2026-10-01T05:49:18+00:00 yes https://xdme.com/watch-book4-q023.html https://xdme.com/book4-thumbs/page-023.jpg Why Do Leaves Have Veins? Veins are roads and drinking straws inside a leaf. They carry water in and sugar out, and they keep the soft leaf blade from flopping. Let's follow the delivery! https://socialmedia.xdme.com/tony/videos-book4/page-023.mp4 https://www.youtube.com/embed/w-Vemqd40Vw 122 2026-10-01T05:56:01+00:00 yes https://xdme.com/watch-book4-q024.html https://xdme.com/book4-thumbs/page-024.jpg Why Do Trees Sway But Not Snap? A living trunk is strong and springy. Bending lets wind energy pass through, instead of breaking the wood the way a stiff pole might. Let's watch a tree ride the wind! https://socialmedia.xdme.com/tony/videos-book4/page-024.mp4 https://www.youtube.com/embed/0IHYnd0VOSM 118 2026-10-01T06:11:45+00:00 yes https://xdme.com/watch-book4-q025.html https://xdme.com/book4-thumbs/page-025.jpg Why Do Forests Need Dead Logs? A fallen log is not trash. It is a slow-release pantry, a sponge, and an apartment building for fungi, bugs, moss, and new seedlings. A dead log is full of life. https://socialmedia.xdme.com/tony/videos-book4/page-025.mp4 https://www.youtube.com/embed/86Dp1MXx8q8 119 2026-10-01T06:17:24+00:00 yes https://xdme.com/watch-book4-q026.html https://xdme.com/book4-thumbs/page-026.jpg Why Do Bees Make Honey? Honey is bee food for winter. Flowers do not bloom all year, so a hive stores extra sugar as thick, long-lasting honey. One bee makes only a tiny amount of honey in her whole life. https://socialmedia.xdme.com/tony/videos-book4/page-026.mp4 https://www.youtube.com/embed/JsMrMYxbYcM 117 2026-10-01T06:36:52+00:00 yes https://xdme.com/watch-book4-q027.html https://xdme.com/book4-thumbs/page-027.jpg Why Do Mosquitoes Bite? Not every mosquito bites people. Many sip plant juices, and only some females take a tiny blood meal, because they need extra protein to make eggs. So a bite is really an egg-makin https://socialmedia.xdme.com/tony/videos-book4/page-027.mp4 https://www.youtube.com/embed/7Fwl97d8BMQ 124 2026-10-01T07:22:44+00:00 yes https://xdme.com/watch-book4-q028.html https://xdme.com/book4-thumbs/page-028.jpg Why Do Spiders Spin Webs? A web is a hunting net and a home alarm. Spider silk is liquid protein that hardens in air into a thread that is very strong for its size. Let's watch a spider build one! https://socialmedia.xdme.com/tony/videos-book4/page-028.mp4 https://www.youtube.com/embed/meDEhDORDHE 119 2026-10-01T08:11:23+00:00 yes https://xdme.com/watch-book4-q029.html https://xdme.com/book4-thumbs/page-029.jpg Why Do Ants Walk in a Line? The line is a smell road. A finder ant lays a scent trail from food to the nest, so the rest of the team can follow without a map. Let's watch an ant road form! https://socialmedia.xdme.com/tony/videos-book4/page-029.mp4 https://www.youtube.com/embed/DGMlladZuzQ 114 2026-10-01T08:21:07+00:00 yes https://xdme.com/watch-book4-q030.html https://xdme.com/book4-thumbs/page-030.jpg Why Do Fireflies Glow? The glow is a living lantern, used as a signal. Many fireflies flash to find a mate, and some young larvae glow too, as a keep-away warning. There are over 2,000 kinds of fireflies https://socialmedia.xdme.com/tony/videos-book4/page-030.mp4 https://www.youtube.com/embed/R36IaeY3IrY 125 2026-10-01T10:08:21+00:00 yes https://xdme.com/watch-book4-q031.html https://xdme.com/book4-thumbs/page-031.jpg Why Do Butterflies Start as Caterpillars? A butterfly is one animal with two jobs. The caterpillar is the eating machine, and the adult is the flying, mating, nectar-sipping machine. In between, the body is rebuilt in a ch https://socialmedia.xdme.com/tony/videos-book4/page-031.mp4 https://www.youtube.com/embed/f-pVJrhrLVk 129 2026-10-01T10:17:02+00:00 yes https://xdme.com/watch-book4-q032.html https://xdme.com/book4-thumbs/page-032.jpg Why Do Worms Come Out After Rain? Wet ground fills the worm's tunnels with water. Worms breathe through damp skin, and coming up is often easier than staying in a flooded tube. Rain is also a good time to travel! https://socialmedia.xdme.com/tony/videos-book4/page-032.mp4 https://www.youtube.com/embed/NDAXpZ2rAtw 120 2026-10-01T10:39:25+00:00 yes https://xdme.com/watch-book4-q033.html https://xdme.com/book4-thumbs/page-033.jpg Why Do Ladybugs Have Spots? Bright red and black is a warning sign. Many ladybugs taste bad, or can leak a bitter fluid. The spots help a bird remember, skip this snack! https://socialmedia.xdme.com/tony/videos-book4/page-033.mp4 https://www.youtube.com/embed/62oC-VGrYTg 124 2026-10-01T10:43:56+00:00 yes https://xdme.com/watch-book4-q034.html https://xdme.com/book4-thumbs/page-034.jpg Why Do Flies Rub Their Feet? A fly tastes with its feet. After a messy landing, rubbing its feet scrapes off dust and sticky food, so the taste sensors work again. It is not waving hello. https://socialmedia.xdme.com/tony/videos-book4/page-034.mp4 https://www.youtube.com/embed/hxyGuHs1jIo 120 2026-10-01T11:01:01+00:00 yes https://xdme.com/watch-book4-q035.html https://xdme.com/book4-thumbs/page-035.jpg Why Do Crickets Chirp? A chirp is a cricket song. Most of the night music you hear is a male, calling to a female, or warning other males away. Only the male crickets make the loud songs. https://socialmedia.xdme.com/tony/videos-book4/page-035.mp4 https://www.youtube.com/embed/wPN4bt7r35I 119 2026-10-01T11:08:10+00:00 yes https://xdme.com/watch-book4-q036.html https://xdme.com/book4-thumbs/page-036.jpg Why Do Snails Carry Shells? A snail shell is a portable house, grown from the snail's own body. It shields the soft parts from drying out, from bumps, and from many hungry mouths. The house is part of the ani https://socialmedia.xdme.com/tony/videos-book4/page-036.mp4 https://www.youtube.com/embed/uwj7X_nJ3qM 116 2026-10-01T11:26:05+00:00 yes https://xdme.com/watch-book4-q037.html https://xdme.com/book4-thumbs/page-037.jpg Why Do Some Bugs Look Like Sticks? A walking stick is an insect that looks just like a twig! That costume is called camouflage, which means hiding by matching your background. If a hungry bird cannot tell lunch from https://socialmedia.xdme.com/tony/videos-book4/page-037.mp4 https://www.youtube.com/embed/manhEx_jNw8 124 2026-09-30T23:13:37+00:00 yes https://xdme.com/watch-book4-q038.html https://xdme.com/book4-thumbs/page-038.jpg Why Do Moths Fly to Lights? Many night moths steer by a faraway light, like the moon. A porch bulb is like a fake moon that sits far too close. So instead of flying straight, the moth's path curls into a spir https://socialmedia.xdme.com/tony/videos-book4/page-038.mp4 https://www.youtube.com/embed/Qi4nKw3aUj0 125 2026-09-30T23:13:38+00:00 yes https://xdme.com/watch-book4-q039.html https://xdme.com/book4-thumbs/page-039.jpg Why Do Ticks Hitch a Ride? A tick is a tiny hitchhiker that needs a blood meal to grow and to make eggs. It cannot fly or jump. So it waits on grass and grabs a passing animal, or even a pant leg. https://socialmedia.xdme.com/tony/videos-book4/page-039.mp4 https://www.youtube.com/embed/aAEHNHtJYHQ 118 2026-09-30T23:43:23+00:00 yes https://xdme.com/watch-book4-q040.html https://xdme.com/book4-thumbs/page-040.jpg Why Do Dragonflies Hover? Hovering is hunting in place! A dragonfly has four wings that can beat in different patterns. So it can stop, dart, and snatch a flying insect right out of the air. https://socialmedia.xdme.com/tony/videos-book4/page-040.mp4 https://www.youtube.com/embed/KRh6nAOtwfs 119 2026-10-01T00:08:42+00:00 yes https://xdme.com/watch-book4-q041.html https://xdme.com/book4-thumbs/page-041.jpg Why Can Ants Lift So Much? An ant is small, but its muscles are thick for its size. On such a tiny body, that strength can move a crumb many times heavier than the ant. Small animals have surprising power! https://socialmedia.xdme.com/tony/videos-book4/page-041.mp4 https://www.youtube.com/embed/pInLL-WItVU 117 2026-10-01T00:42:26+00:00 yes https://xdme.com/watch-book4-q042.html https://xdme.com/book4-thumbs/page-042.jpg Why Do Beetles Have Hard Shells? Those shiny covers on a beetle are armor! They are the front wings, changed into a hard case. The case protects the soft flying wings folded underneath. https://socialmedia.xdme.com/tony/videos-book4/page-042.mp4 https://www.youtube.com/embed/wbYoOgcJTKg 123 2026-10-01T06:02:50+00:00 yes https://xdme.com/watch-book4-q043.html https://xdme.com/book4-thumbs/page-043.jpg Why Do Some Bugs Sting? A sting is a last-ditch guard. Bees, wasps, and some ants use a sharp tool and venom to make a bigger animal back off. The insect is small, so the sting makes the threat feel big e https://socialmedia.xdme.com/tony/videos-book4/page-043.mp4 https://www.youtube.com/embed/kJ1GM-Xc19I 118 2026-10-01T01:00:09+00:00 yes https://xdme.com/watch-book4-q044.html https://xdme.com/book4-thumbs/page-044.jpg Why Do Earthworms Help Gardens? Earthworms are living tillers! They eat dead leaves, leave behind rich castings, and dig tunnels that let air and water into packed dirt. That makes a garden's soil healthier for p https://socialmedia.xdme.com/tony/videos-book4/page-044.mp4 https://www.youtube.com/embed/VLXe2w0PnOA 120 2026-10-01T06:26:15+00:00 yes https://xdme.com/watch-book4-q045.html https://xdme.com/book4-thumbs/page-045.jpg Why Do Cicadas Buzz So Loud? That loud summer roar is a male cicada calling for a mate! Ribs in his abdomen click so fast that they make a buzz that can travel across a whole yard. It takes special body parts https://socialmedia.xdme.com/tony/videos-book4/page-045.mp4 https://www.youtube.com/embed/AjJWSdYo20w 116 2026-10-01T01:31:52+00:00 yes https://xdme.com/watch-book4-q046.html https://xdme.com/book4-thumbs/page-046.jpg Why Do Spiders Have Eight Legs? Spiders are arachnids, not insects. The arachnid body plan comes with eight walking legs, while insects get six. That is one big clue for telling them apart. https://socialmedia.xdme.com/tony/videos-book4/page-046.mp4 https://www.youtube.com/embed/VSF4wF2MNYw 116 2026-10-01T01:40:14+00:00 yes https://xdme.com/watch-book4-q047.html https://xdme.com/book4-thumbs/page-047.jpg Why Do Flies Have Compound Eyes? A compound eye is a bundle of tiny lenses! Together, they make a wide, fast picture. So a fly can spot a swat coming from the side. https://socialmedia.xdme.com/tony/videos-book4/page-047.mp4 https://www.youtube.com/embed/dLqQmeJhBIE 116 2026-10-01T01:48:16+00:00 yes https://xdme.com/watch-book4-q048.html https://xdme.com/book4-thumbs/page-048.jpg Why Do Bees Dance? A honeybee dance is a map in motion! A finder bee tells the hive where good flowers are by walking a figure-eight on the honeycomb. It is like a little treasure map, without a sing https://socialmedia.xdme.com/tony/videos-book4/page-048.mp4 https://www.youtube.com/embed/TJyhSPugZjc 115 2026-10-01T01:54:49+00:00 yes https://xdme.com/watch-book4-q049.html https://xdme.com/book4-thumbs/page-049.jpg Why Do Slugs Leave a Shiny Trail? The shine is slime! A slug makes mucus so its soft foot can glide over rough, dry ground. The slime also helps it stick and stay damp. https://socialmedia.xdme.com/tony/videos-book4/page-049.mp4 https://www.youtube.com/embed/Bw-b4rYUFIY 122 2026-10-01T06:33:43+00:00 yes https://xdme.com/watch-book4-q050.html https://xdme.com/book4-thumbs/page-050.jpg Why Do Bugs Molt? A bug's outer suit is a hard exoskeleton, and it cannot stretch. To get bigger, the animal must crawl out of the old suit. Then it waits for a new one to harden. https://socialmedia.xdme.com/tony/videos-book4/page-050.mp4 https://www.youtube.com/embed/Fd4HrfgJfR8 121 2026-10-01T07:36:24+00:00 yes https://xdme.com/watch-book4-q051.html https://xdme.com/book4-thumbs/page-051.jpg Why Do Birds Sing? A bird song is a message! Many birds sing to claim a territory and to find a mate. The tune says, this tree is taken, and I am healthy. https://socialmedia.xdme.com/tony/videos-book4/page-051.mp4 https://www.youtube.com/embed/plzih90BpQc 122 2026-10-01T08:08:24+00:00 yes https://xdme.com/watch-book4-q052.html https://xdme.com/book4-thumbs/page-052.jpg Why Do Squirrels Bury Nuts? A buried nut is a winter pantry! Food is easy to find in fall, and scarce in snow. So a squirrel hides extra nuts all around the yard. https://socialmedia.xdme.com/tony/videos-book4/page-052.mp4 https://www.youtube.com/embed/1NYnTHk5HRM 121 2026-10-01T09:34:35+00:00 yes https://xdme.com/watch-book4-q053.html https://xdme.com/book4-thumbs/page-053.jpg Why Do Baby Deer Have Spots? A fawn's spots are camouflage! Sun flecks on a forest floor look a lot like a spotted fawn. And a still baby is much harder to see than a running one. https://socialmedia.xdme.com/tony/videos-book4/page-053.mp4 https://www.youtube.com/embed/aVBHerVMlYs 119 2026-10-01T09:54:54+00:00 yes https://xdme.com/watch-book4-q054.html https://xdme.com/book4-thumbs/page-054.jpg Why Do Owls Fly So Quietly? Silence is a hunting tool! An owl that whispers through the air can hear a mouse. It reaches the mouse before the mouse can hear the wings. https://socialmedia.xdme.com/tony/videos-book4/page-054.mp4 https://www.youtube.com/embed/wkkasqEu2b0 125 2026-10-01T10:25:35+00:00 yes https://xdme.com/watch-book4-q055.html https://xdme.com/book4-thumbs/page-055.jpg Why Do Woodpeckers Peck Trees? Pecking is a toolkit! Woodpeckers drum to talk, chip holes to nest, and tap bark to find insect larvae hiding in the wood. It is a bird with many jobs for one little beak. https://socialmedia.xdme.com/tony/videos-book4/page-055.mp4 https://www.youtube.com/embed/cpXmg59QCbc 120 2026-10-01T10:32:38+00:00 yes https://xdme.com/watch-book4-q056.html https://xdme.com/book4-thumbs/page-056.jpg Why Do Frogs Croak After Rain? Rain makes the world safer for frog eggs! Many male frogs croak after a storm to call females to fresh pools. It is a little frog concert, held in the wet. https://socialmedia.xdme.com/tony/videos-book4/page-056.mp4 https://www.youtube.com/embed/l8uz82eRs2M 121 2026-10-01T10:55:29+00:00 yes https://xdme.com/watch-book4-q057.html https://xdme.com/book4-thumbs/page-057.jpg Why Do Snakes Shed Their Skin? A snake wears its skin like a tight sock! The sock cannot grow, so shedding lets the snake get bigger and replaces worn scales. Even the clear scale over the eye gets replaced. https://socialmedia.xdme.com/tony/videos-book4/page-057.mp4 https://www.youtube.com/embed/r9CKiIwyLVg 121 2026-10-01T11:02:32+00:00 yes https://xdme.com/watch-book4-q058.html https://xdme.com/book4-thumbs/page-058.jpg Why Do Bats Fly at Night? Night is an open shift for hunters! Many bats hunt moths and mosquitoes after the birds that hunt by sight have gone to roost. And bats have a special trick for finding food in the https://socialmedia.xdme.com/tony/videos-book4/page-058.mp4 https://www.youtube.com/embed/GoZDIUKakTQ 119 2026-10-01T11:18:21+00:00 yes https://xdme.com/watch-book4-q059.html https://xdme.com/book4-thumbs/page-059.jpg Why Do Beavers Build Dams? A dam makes a beaver pond! Deep, still water hides the lodge door from land hunters. It also lets the family swim to their food in winter, under the ice. https://socialmedia.xdme.com/tony/videos-book4/page-059.mp4 https://www.youtube.com/embed/MqFz51xAn_k 123 2026-10-01T11:30:31+00:00 yes https://xdme.com/watch-book4-q060.html https://xdme.com/book4-thumbs/page-060.jpg Why Do Ducks Have Webbed Feet? Webbed feet are living paddles! The skin between the toes turns each kick into a bigger push through the water. That is why ducks swim so well. https://socialmedia.xdme.com/tony/videos-book4/page-060.mp4 https://www.youtube.com/embed/nMO-rOQ2ujU 123 2026-10-01T11:43:12+00:00 yes https://xdme.com/watch-book4-q061.html https://xdme.com/book4-thumbs/page-061.jpg Why Do Rabbits Freeze, Then Run? Freeze is camouflage, and run is plan B! A still rabbit is harder to spot. If a hunter gets too close, long hind legs launch a zigzag escape. https://socialmedia.xdme.com/tony/videos-book4/page-061.mp4 https://www.youtube.com/embed/4egu9q9IzoU 121 2026-10-01T11:49:44+00:00 yes https://xdme.com/watch-book4-q062.html https://xdme.com/book4-thumbs/page-062.jpg Why Do Porcupines Have Quills? Quills are a stay-back fence! They are modified hairs with tiny barbs. A predator that bites gets a mouthful of trouble, and learns to pick other food. https://socialmedia.xdme.com/tony/videos-book4/page-062.mp4 https://www.youtube.com/embed/co86qeBrzQk 123 2026-10-01T11:53:15+00:00 yes https://xdme.com/watch-book4-q063.html https://xdme.com/book4-thumbs/page-063.jpg Why Do Turtles Hide in Shells? A turtle's shell is its skeleton on the outside! The ribs and backbone are joined to that armor, so the turtle can never take its house off. When danger comes, the soft parts just https://socialmedia.xdme.com/tony/videos-book4/page-063.mp4 https://www.youtube.com/embed/bcq8uEtQJys 122 2026-10-01T11:58:47+00:00 yes https://xdme.com/watch-book4-q064.html https://xdme.com/book4-thumbs/page-064.jpg Why Do Geese Fly in a V? A V is teamwork in the sky! Each bird rides a little lift from the swirl at the wingtip of the bird ahead. So the flock saves energy on long trips. https://socialmedia.xdme.com/tony/videos-book4/page-064.mp4 https://www.youtube.com/embed/1yUTwKeCFn0 122 2026-10-01T12:29:36+00:00 yes https://xdme.com/watch-book4-q065.html https://xdme.com/book4-thumbs/page-065.jpg Why Do Skunks Spray? Spray is a last warning that became a superpower! The smell is so strong that most hunters decide this snack is not worth it. But a skunk would rather not use it. https://socialmedia.xdme.com/tony/videos-book4/page-065.mp4 https://www.youtube.com/embed/AGCOOOKDEPU 124 2026-10-01T12:44:07+00:00 yes https://xdme.com/watch-book4-q066.html https://xdme.com/book4-thumbs/page-066.jpg Why Do Hummingbirds Hover? Hovering lets a hummingbird drink from a flower that cannot hold its weight! The bird is a tiny helicopter with a straw. It hangs in the air while it sips. https://socialmedia.xdme.com/tony/videos-book4/page-066.mp4 https://www.youtube.com/embed/LDYKJnzUBxI 124 2026-10-01T13:02:56+00:00 yes https://xdme.com/watch-book4-q067.html https://xdme.com/book4-thumbs/page-067.jpg Why Do Wolves Howl? A howl is long-distance talk! Pack members can find each other, and claim a valley. They can rally for a hunt without walking the whole forest. https://socialmedia.xdme.com/tony/videos-book4/page-067.mp4 https://www.youtube.com/embed/duMKszdY25k 118 2026-10-01T13:10:00+00:00 yes https://xdme.com/watch-book4-q068.html https://xdme.com/book4-thumbs/page-068.jpg Why Do Raccoons Have Clever Hands? Raccoon front paws are sensitive grabbers! They can feel under water, pop latches, and turn objects. A raccoon explores the world the way your fingers explore a pocket. https://socialmedia.xdme.com/tony/videos-book4/page-068.mp4 https://www.youtube.com/embed/j9PE--OxmXA 122 2026-10-01T13:17:04+00:00 yes https://xdme.com/watch-book4-q069.html https://xdme.com/book4-thumbs/page-069.jpg Why Do Deer Grow Antlers? Antlers are a seasonal crown! Male deer grow them to show strength, and to spar with rivals in the fall breeding season. Then the crown falls off, and a new one starts. https://socialmedia.xdme.com/tony/videos-book4/page-069.mp4 https://www.youtube.com/embed/XFoB_B3MobI 123 2026-10-01T13:23:37+00:00 yes https://xdme.com/watch-book4-q070.html https://xdme.com/book4-thumbs/page-070.jpg Why Do Some Animals Play Dead? Playing dead is a last trick! Some hunters want a chase. A still animal looks like a meal that has already gone bad. The animal is not pretending for fun. The freeze can be automat https://socialmedia.xdme.com/tony/videos-book4/page-070.mp4 https://www.youtube.com/embed/5tNsartftbY 120 2026-10-01T13:30:10+00:00 yes https://xdme.com/watch-book4-q071.html https://xdme.com/book4-thumbs/page-071.jpg Why Do Birds Migrate? Migration is a food-and-weather trip! When insects and berries fade and the cold comes, many birds fly to places that still have meals. They can also nest more safely there later. https://socialmedia.xdme.com/tony/videos-book4/page-071.mp4 https://www.youtube.com/embed/96kdPAn1zJQ 130 2026-10-01T13:37:12+00:00 yes https://xdme.com/watch-book4-q072.html https://xdme.com/book4-thumbs/page-072.jpg Why Do Foxes Have Bushy Tails? A fox tail is a tool kit! It is a winter blanket, a balance pole, and a signal flag, all in one fluffy wrap. No wonder it is so bushy. https://socialmedia.xdme.com/tony/videos-book4/page-072.mp4 https://www.youtube.com/embed/-6U4CLA1wIc 123 2026-10-01T13:54:03+00:00 yes https://xdme.com/watch-book4-q073.html https://xdme.com/book4-thumbs/page-073.jpg Why Do Tracks Look Different in Mud? Mud works like a stamp pad! Soft, wet ground squishes down and takes a deep, sharp print, while dry dust gives a faint, blurry one. The very same foot can look huge in deep mud, an https://socialmedia.xdme.com/tony/videos-book4/page-073.mp4 https://www.youtube.com/embed/7sVifSKXVyw 131 2026-09-30T23:13:39+00:00 yes https://xdme.com/watch-book4-q074.html https://xdme.com/book4-thumbs/page-074.jpg Why Do Some Animals Come Out Only at Night? Night is a different work shift! When the air is cooler, there are fewer daytime hunters around, and there's a buffet of moths and mice. So darkness is a great time to clock in. https://socialmedia.xdme.com/tony/videos-book4/page-074.mp4 https://www.youtube.com/embed/r3-pgG3XWVA 128 2026-09-30T23:13:40+00:00 yes https://xdme.com/watch-book4-q075.html https://xdme.com/book4-thumbs/page-075.jpg Why Can Tracks Tell a Story? A track is like a sentence! A whole line of tracks is like a paragraph. Together they can say who walked here, which way they went, how fast, and whether anyone else joined the wal https://socialmedia.xdme.com/tony/videos-book4/page-075.mp4 https://www.youtube.com/embed/0r1WxUoJYGI 126 2026-10-01T01:19:42+00:00 yes https://xdme.com/watch-book4-q076.html https://xdme.com/book4-thumbs/page-076.jpg Why Is the Sky Blue? Sunlight is a mix of all colors! Tiny air molecules bounce the short blue waves around much more than the other colors, so blue light fills the sky from every direction. That bounc https://socialmedia.xdme.com/tony/videos-book4/page-076.mp4 https://www.youtube.com/embed/bw-E1N27xmE 123 2026-10-01T01:29:30+00:00 yes https://xdme.com/watch-book4-q077.html https://xdme.com/book4-thumbs/page-077.jpg Why Do Clouds Look Fluffy? A fluffy cloud is a crowd of tiny water drops or ice crystals floating together! From the ground, the crowd looks like cotton, because light bounces off all those drops. Each drop https://socialmedia.xdme.com/tony/videos-book4/page-077.mp4 https://www.youtube.com/embed/kNYbuJnUB_Q 125 2026-10-01T01:38:43+00:00 yes https://xdme.com/watch-book4-q078.html https://xdme.com/book4-thumbs/page-078.jpg Why Does Rain Fall? Cloud drops start out tiny! When they bump into each other and grow heavy enough, the air can't hold them up anymore. Gravity wins, and the rain falls. https://socialmedia.xdme.com/tony/videos-book4/page-078.mp4 https://www.youtube.com/embed/g_raY3oIBUM 121 2026-10-01T01:47:15+00:00 yes https://xdme.com/watch-book4-q079.html https://xdme.com/book4-thumbs/page-079.jpg Why Does Thunder Follow Lightning? Lightning is a giant spark! It heats the air so fast that the air explodes outward. That shock wave is thunder. About 5 seconds between flash and boom means the storm is roughly 1 https://socialmedia.xdme.com/tony/videos-book4/page-079.mp4 https://www.youtube.com/embed/fddl7ufbZ4k 126 2026-10-01T01:53:48+00:00 yes https://xdme.com/watch-book4-q080.html https://xdme.com/book4-thumbs/page-080.jpg Why Do Puddles Disappear? A puddle doesn't vanish into nowhere! Some of the water soaks into the ground. The rest turns into invisible vapor and joins the air. https://socialmedia.xdme.com/tony/videos-book4/page-080.mp4 https://www.youtube.com/embed/zwTXUfMA3b4 125 2026-10-01T02:00:20+00:00 yes https://xdme.com/watch-book4-q081.html https://xdme.com/book4-thumbs/page-081.jpg Why Does the Wind Blow? Wind is air on the move! The sun warms some places more than others. Warm air rises, and cooler air slides in to take its place. Wind is invisible. We see what it pushes, like flag https://socialmedia.xdme.com/tony/videos-book4/page-081.mp4 https://www.youtube.com/embed/xIQVFgsOQr0 130 2026-10-01T02:09:29+00:00 yes https://xdme.com/watch-book4-q082.html https://xdme.com/book4-thumbs/page-082.jpg Why Do We See Rainbows? A rainbow is sunlight split apart and sent back by raindrops! Each drop acts like a tiny prism and a tiny mirror at the same time. And the whole bow is made of millions of drops. https://socialmedia.xdme.com/tony/videos-book4/page-082.mp4 https://www.youtube.com/embed/0620SNHriZw 123 2026-10-01T02:31:03+00:00 yes https://xdme.com/watch-book4-q083.html https://xdme.com/book4-thumbs/page-083.jpg Why Does Dew Appear in the Morning? Dew is water from the air that condensed on cool surfaces overnight! It didn't rain. The grass simply got cold enough for water vapor to turn back into drops. https://socialmedia.xdme.com/tony/videos-book4/page-083.mp4 https://www.youtube.com/embed/eYNjpNQnWo0 119 2026-10-01T02:39:38+00:00 yes https://xdme.com/watch-book4-q084.html https://xdme.com/book4-thumbs/page-084.jpg Why Do Lakes Freeze From the Top? Ice is lighter than liquid water, so it floats! Cold air nips the surface first, and the ice lid then covers the water below like a blanket. That means fish can keep living underne https://socialmedia.xdme.com/tony/videos-book4/page-084.mp4 https://www.youtube.com/embed/uJebPmRJzq0 123 2026-10-01T02:50:41+00:00 yes https://xdme.com/watch-book4-q085.html https://xdme.com/book4-thumbs/page-085.jpg Why Do Rivers Flow Downhill? Gravity pulls water toward the lowest spot it can reach! A river is rain and melted snow sliding downhill in a channel, headed for a lake or the sea. Water can't hold a pile, so it https://socialmedia.xdme.com/tony/videos-book4/page-085.mp4 https://www.youtube.com/embed/NUYFB98dJi8 119 2026-10-01T02:59:06+00:00 yes https://xdme.com/watch-book4-q086.html https://xdme.com/book4-thumbs/page-086.jpg Why Do Waves Keep Coming? Most waves are wind energy traveling through water! The water mostly just goes up and down. It's the energy that keeps rolling toward the shore. https://socialmedia.xdme.com/tony/videos-book4/page-086.mp4 https://www.youtube.com/embed/YnC_8DuxXRc 118 2026-10-01T03:11:16+00:00 yes https://xdme.com/watch-book4-q087.html https://xdme.com/book4-thumbs/page-087.jpg Why Is the Ocean Salty? Rivers carry tiny bits of dissolved rock and salt to the sea! Water evaporates from the ocean, but the salt stays behind, and slowly builds up. It takes a very long time. https://socialmedia.xdme.com/tony/videos-book4/page-087.mp4 https://www.youtube.com/embed/kqn4SHjRZEQ 123 2026-10-01T03:27:48+00:00 yes https://xdme.com/watch-book4-q088.html https://xdme.com/book4-thumbs/page-088.jpg Why Does Fog Hug the Ground? Fog is a cloud that formed at ground level! When cool air near the ground makes water vapor condense, you get tiny drops that you can walk through. Those drops hang right where the https://socialmedia.xdme.com/tony/videos-book4/page-088.mp4 https://www.youtube.com/embed/ETnDTMgizeI 117 2026-10-01T03:37:29+00:00 yes https://xdme.com/watch-book4-q089.html https://xdme.com/book4-thumbs/page-089.jpg Why Do We Have Seasons? Earth is tilted! As it goes around the sun, one half leans toward the sun for part of the year, and away for the other part. That tilt is what makes the seasons. https://socialmedia.xdme.com/tony/videos-book4/page-089.mp4 https://www.youtube.com/embed/VXGJZhmul3Y 117 2026-10-01T03:56:41+00:00 yes https://xdme.com/watch-book4-q090.html https://xdme.com/book4-thumbs/page-090.jpg Why Does Snow Sparkle? Snow is a pile of tiny ice crystals! Their flat faces act like little mirrors. When the sun hits those faces just right, you see flashes. https://socialmedia.xdme.com/tony/videos-book4/page-090.mp4 https://www.youtube.com/embed/ONBGYQsKA4g 118 2026-10-01T04:08:24+00:00 yes https://xdme.com/watch-book4-q091.html https://xdme.com/book4-thumbs/page-091.jpg Why Do Icicles Hang From Roofs? An icicle is meltwater that froze again on the way down! A warm patch of roof melts the snow. Then the drip hits cold air, and builds a hanging spike. https://socialmedia.xdme.com/tony/videos-book4/page-091.mp4 https://www.youtube.com/embed/-R8Wh65HbJ8 118 2026-10-01T04:17:58+00:00 yes https://xdme.com/watch-book4-q092.html https://xdme.com/book4-thumbs/page-092.jpg Why Does the Moon Look Bigger Some Nights? A huge moon near the horizon is mostly a trick of the brain! Trees and houses give the moon neighbors to compare with, so it looks giant. High in the empty sky, it looks smaller. https://socialmedia.xdme.com/tony/videos-book4/page-092.mp4 https://www.youtube.com/embed/IIGvXdmvuPg 116 2026-10-01T04:36:04+00:00 yes https://xdme.com/watch-book4-q093.html https://xdme.com/book4-thumbs/page-093.jpg Why Do Stars Twinkle? Stars don't really blink on and off! It's our air that is jumpy. Pockets of warmer and cooler air bend the starlight as it comes in, so the point of light seems to dance. https://socialmedia.xdme.com/tony/videos-book4/page-093.mp4 https://www.youtube.com/embed/6KRL-WaRIS8 125 2026-10-01T04:52:21+00:00 yes https://xdme.com/watch-book4-q094.html https://xdme.com/book4-thumbs/page-094.jpg Why Is Sunset Orange and Red? At sunset, sunlight takes a much longer path through the air! On the way, the blue light gets scattered out of the beam. The leftover light that reaches your eyes is orange and red https://socialmedia.xdme.com/tony/videos-book4/page-094.mp4 https://www.youtube.com/embed/pzE4fMcAVjw 119 2026-10-01T05:09:38+00:00 yes https://xdme.com/watch-book4-q095.html https://xdme.com/book4-thumbs/page-095.jpg Why Do We Have Day and Night? Earth spins like a top! The half facing the sun has day, and the half turned away has night. One full spin takes about 24 hours. It is always daytime somewhere on Earth. https://socialmedia.xdme.com/tony/videos-book4/page-095.mp4 https://www.youtube.com/embed/_OkJiQV0Dvk 117 2026-10-01T05:16:41+00:00 yes https://xdme.com/watch-book4-q096.html https://xdme.com/book4-thumbs/page-096.jpg Why Do We See Our Breath in Winter? Your breath is warm and damp! Cold air can't hold all that water vapor, so it turns into a tiny fog right in front of your mouth. That's the puff you see. https://socialmedia.xdme.com/tony/videos-book4/page-096.mp4 https://www.youtube.com/embed/Dxlkjl3ppTM 122 2026-10-01T05:25:56+00:00 yes https://xdme.com/watch-book4-q097.html https://xdme.com/book4-thumbs/page-097.jpg Why Does a Compass Point North? Earth is a giant magnet! A compass needle is a tiny magnet that can spin freely. It lines up with Earth's magnetic field, so one end points near geographic north. https://socialmedia.xdme.com/tony/videos-book4/page-097.mp4 https://www.youtube.com/embed/ZjsDWtJjSVc 120 2026-10-01T05:33:32+00:00 yes https://xdme.com/watch-book4-q098.html https://xdme.com/book4-thumbs/page-098.jpg Why Does Frost Paint the Grass? Frost is dew's frozen cousin! When grass gets colder than freezing, water vapor can turn straight into ice crystals on the blades. It paints the grass white. https://socialmedia.xdme.com/tony/videos-book4/page-098.mp4 https://www.youtube.com/embed/eRHdH9YoPMw 118 2026-10-01T05:45:13+00:00 yes https://xdme.com/watch-book4-q099.html https://xdme.com/book4-thumbs/page-099.jpg Why Do Storms Have Calm and Wild Parts? A storm is like a weather engine with different rooms! Rising warm air, falling rain, and spinning winds are not the same in every spot. So one minute can roar, and the next can hu https://socialmedia.xdme.com/tony/videos-book4/page-099.mp4 https://www.youtube.com/embed/Mcq6KH-Iq0M 116 2026-10-01T05:49:57+00:00 yes https://xdme.com/watch-book4-q100.html https://xdme.com/book4-thumbs/page-100.jpg Why Can a Weather Forecast Miss? Weather is a giant puzzle with too many moving pieces! A forecast is the best science guess from computer models, satellites, and radars. It's not a promise carved in stone. https://socialmedia.xdme.com/tony/videos-book4/page-100.mp4 https://www.youtube.com/embed/D4l6wQsStSM 119 2026-10-01T06:06:32+00:00 yes https://xdme.com/watch-book4-q101.html https://xdme.com/book4-thumbs/page-101.jpg Why Do Ponds Get a Green Film in Summer? That green film is often algae! Algae are tiny plant-like living things. With warm sun, still water, and extra nutrients, they bloom into a scum you can see. https://socialmedia.xdme.com/tony/videos-book4/page-101.mp4 https://www.youtube.com/embed/0RGzjd1KyM8 123 2026-10-01T06:12:19+00:00 yes https://xdme.com/watch-book4-q102.html https://xdme.com/book4-thumbs/page-102.jpg Why Do Frogs Start as Tadpoles? A tadpole is a frog's water-baby shape! Frog eggs are laid in water, so the first body is built for swimming and eating pond food. Later it rebuilds itself for life on land. https://socialmedia.xdme.com/tony/videos-book4/page-102.mp4 https://www.youtube.com/embed/njxdaEnuz4I 122 2026-10-01T06:31:40+00:00 yes https://xdme.com/watch-book4-q103.html https://xdme.com/book4-thumbs/page-103.jpg Why Do Ducks' Feathers Shed Water? Duck feathers overlap like shingles on a roof! A duck also gets a thin coat of oil from a gland near its tail, so water beads up and rolls off instead of soaking in. It's a built-i https://socialmedia.xdme.com/tony/videos-book4/page-103.mp4 https://www.youtube.com/embed/LPl_NSqIWkk 118 2026-10-01T06:39:07+00:00 yes https://xdme.com/watch-book4-q104.html https://xdme.com/book4-thumbs/page-104.jpg Why Do Some Fish Swim in Schools? A school is a moving crowd of fish! Many eyes spot danger, and the group can twist together, so a hunter has a harder time picking just one fish. There's safety in numbers. https://socialmedia.xdme.com/tony/videos-book4/page-104.mp4 https://www.youtube.com/embed/zjNhwxp8pMA 118 2026-10-01T08:26:38+00:00 yes https://xdme.com/watch-book4-q105.html https://xdme.com/book4-thumbs/page-105.jpg Why Do Water Striders Walk on Water? A pond has a thin skin called surface tension! A water strider is light, and its long legs spread out its weight. Its hairy feet make little dimples in the skin, instead of punchin https://socialmedia.xdme.com/tony/videos-book4/page-105.mp4 https://www.youtube.com/embed/qyr8367P2S0 125 2026-10-01T08:14:50+00:00 yes https://xdme.com/watch-book4-q106.html https://xdme.com/book4-thumbs/page-106.jpg Why Do Mosquitoes Hatch Near Water? Mosquito babies are aquatic! Eggs are laid on still water. The wrigglers breathe at the surface and eat tiny bits until they become flying adults. https://socialmedia.xdme.com/tony/videos-book4/page-106.mp4 https://www.youtube.com/embed/eGKoLmLZBbE 120 2026-10-01T09:59:38+00:00 yes https://xdme.com/watch-book4-q107.html https://xdme.com/book4-thumbs/page-107.jpg Why Does a Stream Make a Bubbling Sound? Moving water slams into rocks and folds over itself! Air gets trapped in the water and pops. Those pops, plus the rush of the water, are the stream's voice. https://socialmedia.xdme.com/tony/videos-book4/page-107.mp4 https://www.youtube.com/embed/5b5Ij0QrVpk 118 2026-10-01T10:08:24+00:00 yes https://xdme.com/watch-book4-q108.html https://xdme.com/book4-thumbs/page-108.jpg Why Do Crayfish Hide Under Rocks? A crayfish is a snack with a shell! Rocks, logs, and burrows hide it from fish, birds, and raccoons. The dark gap is both a fortress and a hunting blind. https://socialmedia.xdme.com/tony/videos-book4/page-108.mp4 https://www.youtube.com/embed/GuTcOpafPo4 119 2026-10-01T10:30:37+00:00 yes https://xdme.com/watch-book4-q109.html https://xdme.com/book4-thumbs/page-109.jpg Why Do Cattails Grow in Wet Ditches? Cattails are wetland plants. Their roots like soggy soil, and their stems are built to stand in shallow water. A wet ditch stays wet for a long time, so it is a perfect home for th https://socialmedia.xdme.com/tony/videos-book4/page-109.mp4 https://www.youtube.com/embed/1iVpLy3Sink 125 2026-09-30T23:14:42+00:00 yes https://xdme.com/watch-book4-q110.html https://xdme.com/book4-thumbs/page-110.jpg Why Do Turtles Bask on Logs? Turtles are cold-blooded, so they use the sun as a heater. Water steals heat, but air and sunshine give it back. A log is a dry, safe bench where a turtle can warm up. https://socialmedia.xdme.com/tony/videos-book4/page-110.mp4 https://www.youtube.com/embed/SZECxjh6W14 123 2026-09-30T23:14:44+00:00 yes https://xdme.com/watch-book4-q111.html https://xdme.com/book4-thumbs/page-111.jpg Why Do Beavers Build Dams? Nature's Engineers A dam is a beaver's tool for making deep, still water. Beavers are nature's engineers. Their pond is a safe home that protects the family, like a moat around a castle. https://socialmedia.xdme.com/tony/videos-book4/page-111.mp4 https://www.youtube.com/embed/DLg-JpGmFEc 123 2026-09-30T23:14:45+00:00 yes https://xdme.com/watch-book4-q112.html https://xdme.com/book4-thumbs/page-112.jpg Why Do Snails Leave Shiny Trails? The shine is mucus, a slippery slime that a snail makes itself. It works like a lubricant and a glue. It lets the snail slide along without tearing its soft foot. https://socialmedia.xdme.com/tony/videos-book4/page-112.mp4 https://www.youtube.com/embed/fTy8S4suHQU 120 2026-09-30T23:14:46+00:00 yes https://xdme.com/watch-book4-q113.html https://xdme.com/book4-thumbs/page-113.jpg Why Do Salamanders Like Damp Logs? Many salamanders breathe partly through thin, wet skin. Dry air can pull water out of that skin. The underside of a damp log stays cool and moist, so it works like a humid little c https://socialmedia.xdme.com/tony/videos-book4/page-113.mp4 https://www.youtube.com/embed/nYWIeRRD8dk 115 2026-09-30T23:14:47+00:00 yes https://xdme.com/watch-book4-q114.html https://xdme.com/book4-thumbs/page-114.jpg Why Do Wetlands Soak Up Floods? A wetland is like a giant sponge. Water spreads out into shallow basins, and plants and spongy ground hold it. Then the water drips out slowly, instead of rushing downstream all at https://socialmedia.xdme.com/tony/videos-book4/page-114.mp4 https://www.youtube.com/embed/Pi9RS0yCUuQ 117 2026-09-30T23:14:48+00:00 yes https://xdme.com/watch-book4-q115.html https://xdme.com/book4-thumbs/page-115.jpg Why Do Caddisfly Larvae Wear Stick Suits? A caddisfly larva has a soft body. It builds a portable case, like a tiny suit, to hide inside. The suit is a walking cave made of sand, sticks, or stones. https://socialmedia.xdme.com/tony/videos-book4/page-115.mp4 https://www.youtube.com/embed/F6oZvoK-YAA 118 2026-09-30T23:14:49+00:00 yes https://xdme.com/watch-book4-q116.html https://xdme.com/book4-thumbs/page-116.jpg Why Do Frogs Croak After Rain? The Pond Chorus Rain makes travel and breeding easier for frogs. Wet ground does not dry out their skin, and puddles and ponds fill up. Many male frogs call to say, I am here, and to attract a mat https://socialmedia.xdme.com/tony/videos-book4/page-116.mp4 https://www.youtube.com/embed/tQD38cyg8sQ 120 2026-09-30T23:23:51+00:00 yes https://xdme.com/watch-book4-q117.html https://xdme.com/book4-thumbs/page-117.jpg Why Do Some Ponds Freeze While Springs Stay Open? A still pond loses heat at its surface and can grow an ice lid. A spring has moving water that comes from underground. That water is not winter-cold, and it keeps moving, so ice ha https://socialmedia.xdme.com/tony/videos-book4/page-117.mp4 https://www.youtube.com/embed/7C0v6jbwue4 120 2026-10-01T00:08:11+00:00 yes https://xdme.com/watch-book4-q118.html https://xdme.com/book4-thumbs/page-118.jpg Why Do Ducks Dabble Upside Down? Dabbling is shallow-water grocery shopping. A duck tips its tail up and its head down to reach food on the bottom. Plants, seeds, and tiny animals are waiting in the mud. https://socialmedia.xdme.com/tony/videos-book4/page-118.mp4 https://www.youtube.com/embed/8yuvJklgnVs 113 2026-10-01T01:03:40+00:00 yes https://xdme.com/watch-book4-q119.html https://xdme.com/book4-thumbs/page-119.jpg Why Should You Not Drink Stream Water? Clear water can still hide germs. You cannot see viruses or many bacteria, so pretty water is not always safe water. Streams pick up droppings and runoff from animals, fields, and https://socialmedia.xdme.com/tony/videos-book4/page-119.mp4 https://www.youtube.com/embed/FIbcJKD3h-8 121 2026-10-01T03:20:31+00:00 yes https://xdme.com/watch-book4-q120.html https://xdme.com/book4-thumbs/page-120.jpg Why Is the Forest Louder at Night? For many animals, night is rush hour. Frogs, insects, owls, and mammals that hide by day clock in for their night shift. The woods are not angry or scary. https://socialmedia.xdme.com/tony/videos-book4/page-120.mp4 https://www.youtube.com/embed/piKLxvDFRMg 115 2026-10-01T04:31:16+00:00 yes https://xdme.com/watch-book4-q121.html https://xdme.com/book4-thumbs/page-121.jpg Why Do Fireflies Light Up? A firefly's glow is a chemical lantern in its belly. A special reaction makes cold light with almost no heat. Each species blinks in its own pattern, like a secret code that says, https://socialmedia.xdme.com/tony/videos-book4/page-121.mp4 https://www.youtube.com/embed/Pib0nks61dU 119 2026-10-01T04:43:23+00:00 yes https://xdme.com/watch-book4-q122.html https://xdme.com/book4-thumbs/page-122.jpg Why Do Owls Fly So Quietly? Think Like the Mouse An owl hunts mostly by listening, and a mouse has sharp ears too. If the owl's wings were loud, the mouse would hear a warning and run away, so owls are built to hush the air. https://socialmedia.xdme.com/tony/videos-book4/page-122.mp4 https://www.youtube.com/embed/LLrFeaO2VyY 117 2026-10-01T05:04:52+00:00 yes https://xdme.com/watch-book4-q123.html https://xdme.com/book4-thumbs/page-123.jpg Why Do Bats Zip Around at Dusk? Dusk is insect rush hour. Many bats are night fliers that hunt with sound, and they zip where mosquitoes and moths rise. One bat can eat a big pile of night insects in an evening. https://socialmedia.xdme.com/tony/videos-book4/page-123.mp4 https://www.youtube.com/embed/Tda9euCnw-w 112 2026-10-01T05:13:09+00:00 yes https://xdme.com/watch-book4-q124.html https://xdme.com/book4-thumbs/page-124.jpg Why Do Some Flowers Smell Stronger at Night? Some plants clock their perfume for moths and other night pollinators. Color is harder to see after dark, so scent becomes the billboard. A flower that seems shy at noon can own th https://socialmedia.xdme.com/tony/videos-book4/page-124.mp4 https://www.youtube.com/embed/viaMfvJMN00 114 2026-10-01T05:22:17+00:00 yes https://xdme.com/watch-book4-q125.html https://xdme.com/book4-thumbs/page-125.jpg Why Do Raccoons Look So Busy After Dark? Raccoons are night-shift generalists, which means they eat almost anything. Dark hours mean fewer people and some easier prey. Their super-sensitive front paws can feel for food, l https://socialmedia.xdme.com/tony/videos-book4/page-125.mp4 https://www.youtube.com/embed/hd8YV3gUaUg 119 2026-10-01T05:29:29+00:00 yes https://xdme.com/watch-book4-q126.html https://xdme.com/book4-thumbs/page-126.jpg Why Do Moths Fly at Lights? Many moths steer by a distant light, like the moon. Keeping it at a steady angle works like a night compass. A nearby bulb is a fake moon, so the moth is not in love with your lamp https://socialmedia.xdme.com/tony/videos-book4/page-126.mp4 https://www.youtube.com/embed/lPAwWv8RLk8 117 2026-10-01T05:38:39+00:00 yes https://xdme.com/watch-book4-q127.html https://xdme.com/book4-thumbs/page-127.jpg Why Do We Hear Coyotes at Night? Howls and yips are messages. Coyotes use them to say, we are here, and to keep in touch with family and neighbors. Night is when coyotes hunt and travel, and people and heat are lo https://socialmedia.xdme.com/tony/videos-book4/page-127.mp4 https://www.youtube.com/embed/tWyRJZWN2sk 111 2026-10-01T05:45:14+00:00 yes https://xdme.com/watch-book4-q128.html https://xdme.com/book4-thumbs/page-128.jpg Why Do Eyes Shine in a Flashlight? Many night animals have a mirror layer at the back of the eye called the [tapetum, tah-PEE-tum]. Light goes in, bounces off it, and comes back out. That bounce gives the eye a seco https://socialmedia.xdme.com/tony/videos-book4/page-128.mp4 https://www.youtube.com/embed/I34Wpu5rEEU 117 2026-10-01T05:56:02+00:00 yes https://xdme.com/watch-book4-q129.html https://xdme.com/book4-thumbs/page-129.jpg Why Do Slugs Come Out After Dark? A slug is like a water balloon with a foot. Its slime needs moisture, and daytime sun and dry air can dry it out. After dark the ground is cooler and damper, so it is the perfect t https://socialmedia.xdme.com/tony/videos-book4/page-129.mp4 https://www.youtube.com/embed/rtNx4IWZpL4 113 2026-10-01T06:01:19+00:00 yes https://xdme.com/watch-book4-q130.html https://xdme.com/book4-thumbs/page-130.jpg Why Do Some Animals See Well at Night? Night hunters pack extra tools into their eyes. A wide pupil lets in more light, and special cells called rods catch dim light. Many also have a mirror layer that gives light a sec https://socialmedia.xdme.com/tony/videos-book4/page-130.mp4 https://www.youtube.com/embed/lDfJQiI7sM8 113 2026-10-01T06:17:24+00:00 yes https://xdme.com/watch-book4-q131.html https://xdme.com/book4-thumbs/page-131.jpg Why Do Night Insects Sound Like a Band? Crickets, katydids, and some frogs all clock in as night singers. Each species has its own instrument and its own pattern and tempo. So the woods sound like a messy, wonderful orch https://socialmedia.xdme.com/tony/videos-book4/page-131.mp4 https://www.youtube.com/embed/Ec9oJeNQapM 106 2026-10-01T06:24:37+00:00 yes https://xdme.com/watch-book4-q132.html https://xdme.com/book4-thumbs/page-132.jpg Why Do Porcupines Wander After Dusk? A porcupine is a slow, night-shift plant eater. Dusk means fewer busy roads, and wandering lets this clumsy climber work while many hunters nap. Its quills are a warning coat, not https://socialmedia.xdme.com/tony/videos-book4/page-132.mp4 https://www.youtube.com/embed/GPhqpcnXD1c 112 2026-10-01T07:19:53+00:00 yes https://xdme.com/watch-book4-q133.html https://xdme.com/book4-thumbs/page-133.jpg Why Do Night Hikers Use Red Light? Rod cells in your eyes do most of your night vision, and they respond much less to red light. A dim red light lets your eyes stay dark-adapted. A bright white beam wipes out that a https://socialmedia.xdme.com/tony/videos-book4/page-133.mp4 https://www.youtube.com/embed/Pwjc53PyAGI 113 2026-10-01T07:36:25+00:00 yes https://xdme.com/watch-book4-q134.html https://xdme.com/book4-thumbs/page-134.jpg Why Do Crickets Chirp After Sunset? A male cricket rubs a file on one wing against a scraper on the other wing to make a chirp. The chirp is a night advertisement that says, I am here, and I am your kind. Cooler, dar https://socialmedia.xdme.com/tony/videos-book4/page-134.mp4 https://www.youtube.com/embed/D7GSaotLlzU 125 2026-10-01T11:57:46+00:00 yes https://xdme.com/watch-book4-q135.html https://xdme.com/book4-thumbs/page-135.jpg Why Do Deer Freeze in Headlights? A sudden blast of bright light can overwhelm a night-adapted eye. It is like a noon sun switched on in one second. The deer is not being brave or silly. https://socialmedia.xdme.com/tony/videos-book4/page-135.mp4 https://www.youtube.com/embed/9zZmd-ZJVms 125 2026-10-01T12:27:49+00:00 yes https://xdme.com/watch-book4-q136.html https://xdme.com/book4-thumbs/page-136.jpg Why Do Mushrooms Seem to Pop Up Overnight? The mushroom you see is just the fruit. The real body of the fungus is a hidden web of threads in the wood or soil. That web may have been there for months, and then water helps th https://socialmedia.xdme.com/tony/videos-book4/page-136.mp4 https://www.youtube.com/embed/i7rj6p3OS5w 124 2026-10-01T12:41:32+00:00 yes https://xdme.com/watch-book4-q137.html https://xdme.com/book4-thumbs/page-137.jpg Why Do Trail Markers Matter in the Dark? Night steals the landmarks. Trees look alike after dusk, and your brain has fewer clues to use. A painted mark or a numbered post is a signal that says, this is still the path. https://socialmedia.xdme.com/tony/videos-book4/page-137.mp4 https://www.youtube.com/embed/FP-JDQqrlNI 122 2026-10-01T13:01:25+00:00 yes https://xdme.com/watch-book4-q138.html https://xdme.com/book4-thumbs/page-138.jpg Why Should You Not Follow Glowing Eyes Off-Trail? Glowing eyes are a clue, not an invitation. Off the trail there are roots, holes, and water, and you can lose the path fast. The animal also loses its calm, so it is best for both https://socialmedia.xdme.com/tony/videos-book4/page-138.mp4 https://www.youtube.com/embed/2dIKiYbGRD8 121 2026-10-01T13:08:27+00:00 yes https://xdme.com/watch-book4-q139.html https://xdme.com/book4-thumbs/page-139.jpg Why Does a Campfire Look Extra Bright at Night? The fire did not get hotter just because the sun left. Your eyes adapted to the dim woods, so the same flames look like a spotlight. A small bright flame against black trees also m https://socialmedia.xdme.com/tony/videos-book4/page-139.mp4 https://www.youtube.com/embed/AUEmJtrSAGA 122 2026-10-01T13:15:32+00:00 yes https://xdme.com/watch-book4-q140.html https://xdme.com/book4-thumbs/page-140.jpg Why Do We Hear More When We Stop Walking? Your own feet, jacket, and whispers are like a marching band. When you freeze, that band stops, and the real woods can reach your ears. Stopping also lets your eyes finish adapting https://socialmedia.xdme.com/tony/videos-book4/page-140.mp4 https://www.youtube.com/embed/14ATLtItAVE 122 2026-10-01T13:22:36+00:00 yes https://xdme.com/watch-book4-q141.html https://xdme.com/book4-thumbs/page-141.jpg Why Do Some Trees Creak at Night? Wood is not a silent statue. Wind, cooling air, and branches rubbing together can all make a tree groan. A creak can sound like footsteps, but it is usually just the tree working. https://socialmedia.xdme.com/tony/videos-book4/page-141.mp4 https://www.youtube.com/embed/UH8F3K9D8gQ 122 2026-10-01T13:29:08+00:00 yes https://xdme.com/watch-book4-q142.html https://xdme.com/book4-thumbs/page-142.jpg Why Do Night Hikers Stay Together? Staying together is how you get the story home. A group shares lights, maps, and the job of watching. Teamwork is a science tool, and detectives do not wander off alone. https://socialmedia.xdme.com/tony/videos-book4/page-142.mp4 https://www.youtube.com/embed/7mH2ydDmX-A 123 2026-10-01T13:35:41+00:00 yes https://xdme.com/watch-book4-q143.html https://xdme.com/book4-thumbs/page-143.jpg Why Do a Map and a Grown-Up Beat Wandering? Curiosity is the engine, but a map and a grown-up are the steering wheel. Night wandering turns a question into a search party. Wonder still happens on a marked loop with a plan. https://socialmedia.xdme.com/tony/videos-book4/page-143.mp4 https://www.youtube.com/embed/oDZUbQ9PB_w 122 2026-10-01T13:52:32+00:00 yes https://xdme.com/watch-book4-q144.html https://xdme.com/book4-thumbs/page-144.jpg How Do You Think Like a Nature Detective? A nature detective asks why, looks twice, and leaves the scene better than they found it. Clues are tracks, songs, weather, and timing, and you collect them with your eyes and a no https://socialmedia.xdme.com/tony/videos-book4/page-144.mp4 https://www.youtube.com/embed/mMULK5PzhcY 122 2026-10-01T13:59:04+00:00 yes https://xdme.com/watch-book4-q145.html https://xdme.com/book4-thumbs/page-145.jpg Why Do Dragonflies Dart Over Ponds? Dragonflies dart over ponds because a pond is their hunting ground! Ponds are full of tiny flying insects, and the water is where baby dragonflies grow up. So grown-up dragonflies https://socialmedia.xdme.com/tony/videos-book4/page-145.mp4 https://www.youtube.com/embed/6XYBeGkZrZ8 125 2026-10-03T22:11:20+00:00 yes https://xdme.com/watch-book4-q146.html https://xdme.com/book4-thumbs/page-146.jpg Why Is Pond Water Brown Sometimes? Pond water turns brown when bits of nature get mixed into it! Soil washes in with the rain, and old leaves soak in the water like a tea bag. Both can color the pond. https://socialmedia.xdme.com/tony/videos-book4/page-146.mp4 https://www.youtube.com/embed/0kfvou6fLJk 120 2026-10-03T22:16:44+00:00 yes https://xdme.com/watch-book4-q147.html https://xdme.com/book4-thumbs/page-147.jpg Why Do Tadpoles Lose Their Tails? A tadpole's tail doesn't fall off. Its body slowly uses it up! The tail is a swimming tool, and a froglet doesn't need it. This big body change is called metamorphosis. https://socialmedia.xdme.com/tony/videos-book4/page-147.mp4 https://www.youtube.com/embed/nWVt2xxuYiw 123 2026-10-03T22:21:15+00:00 yes https://xdme.com/watch-book4-q148.html https://xdme.com/book4-thumbs/page-148.jpg Why Do Herons Stand So Still? Herons stand still because they are hunting! Fish and frogs can see movement, so a heron holds very quiet in the shallow water. When prey swims close, the heron strikes in a flash. https://socialmedia.xdme.com/tony/videos-book4/page-148.mp4 https://www.youtube.com/embed/sIKIWu6U9BQ 116 2026-10-03T22:24:20+00:00 yes https://xdme.com/watch-book4-q149.html https://xdme.com/book4-thumbs/page-149.jpg Why Do Minnows Hide in Weeds? Minnows hide in weeds because the weeds keep them safe! Minnows are small, so bigger fish, birds, and turtles love to eat them. A thick patch of plants gives them cover, shade, and https://socialmedia.xdme.com/tony/videos-book4/page-149.mp4 https://www.youtube.com/embed/sYr9GG4cGF0 123 2026-10-03T22:27:51+00:00 yes https://xdme.com/watch-book4-q150.html https://xdme.com/book4-thumbs/page-150.jpg Why Do Lily Pads Float? Lily pads float because they are flat, light, and full of air! Each pad is wide and thin, like a raft. Tiny air spaces inside make it even lighter. https://socialmedia.xdme.com/tony/videos-book4/page-150.mp4 https://www.youtube.com/embed/ZbCo1JQjOUE 117 2026-10-03T22:30:54+00:00 yes https://xdme.com/watch-book5-q001.html https://xdme.com/book5-thumbs/page-001.jpg Giant Dinos! Why Were Some Dinosaurs So Huge? Some plant-eating dinosaurs, called sauropods, were among the biggest animals ever to walk on land. Scientists think lots of plants to eat, hollow air-filled spaces inside their bo https://socialmedia.xdme.com/tony/videos-book2/page-001.mp4 https://www.youtube.com/embed/lykhuqCmJXo 127 2026-09-29T15:20:21+00:00 yes https://xdme.com/watch-book5-q002.html https://xdme.com/book5-thumbs/page-002.jpg Tiny Arms, Huge Bite! Why Did T. Rex Have Tiny Arms? Tyrannosaurus rex had arms that looked tiny next to its giant body, but they were short and very strong. Its most powerful tool was its enormous head with a mighty bite. Scientists https://socialmedia.xdme.com/tony/videos-book2/page-002.mp4 https://www.youtube.com/embed/a0bwhluMxk8 123 2026-09-29T15:20:22+00:00 yes https://xdme.com/watch-book5-q003.html https://xdme.com/book5-thumbs/page-003.jpg Fluffy Fossils! Why Do We Think Dinosaurs Had Feathers? Some amazing fossils show the marks of feather-like coverings on dinosaurs, and some of them are preserved in great detail. Feathers could have helped keep a dinosaur warm or been https://socialmedia.xdme.com/tony/videos-book2/page-003.mp4 https://www.youtube.com/embed/RbgD0TGCsnk 130 2026-09-29T15:20:23+00:00 yes https://xdme.com/watch-book5-q004.html https://xdme.com/book5-thumbs/page-004.jpg Reach for the Sky! Why Long Necks on Some Dinosaurs? Long-necked dinosaurs, called sauropods, could stretch their necks to reach lots of leaves without moving their huge bodies much. Their neck bones had air spaces inside, which help https://socialmedia.xdme.com/tony/videos-book2/page-004.mp4 https://www.youtube.com/embed/pNCwccc7lSs 128 2026-09-29T15:20:24+00:00 yes https://xdme.com/watch-book5-q005.html https://xdme.com/book5-thumbs/page-005.jpg Plates on Its Back? Why Did Stegosaurus Have Them? Stegosaurus had a row of big bony plates along its back and spikes on its tail. Scientists think the plates may have been for display, helping animals recognize each other, and may https://socialmedia.xdme.com/tony/videos-book2/page-005.mp4 https://www.youtube.com/embed/OJ-PUFfpFNg 122 2026-09-29T15:20:25+00:00 yes https://xdme.com/watch-book5-q006.html https://xdme.com/book5-thumbs/page-006.jpg Horns and a Frill! Why Did Triceratops Have Both? Triceratops had three horns and a wide bony frill behind its head. Scientists think these could have helped in defense, in showing off, and in telling one Triceratops from another. https://socialmedia.xdme.com/tony/videos-book2/page-006.mp4 https://www.youtube.com/embed/K8eocM3ASxE 120 2026-09-29T14:38:55+00:00 yes https://xdme.com/watch-book5-q007.html https://xdme.com/book5-thumbs/page-007.jpg Pocket-Sized Dinos! Why Were Some Dinosaurs So Small? Not every dinosaur was a giant! Some were only about the size of a turkey or a chicken. A small body needs less food and can hide in small places, so being little worked well for t https://socialmedia.xdme.com/tony/videos-book2/page-007.mp4 https://www.youtube.com/embed/Wab61UGH4Fg 120 2026-09-29T14:39:26+00:00 yes https://xdme.com/watch-book5-q008.html https://xdme.com/book5-thumbs/page-008.jpg Egg-cellent Question! Why Did Dinosaurs Lay Eggs? Dinosaurs laid eggs, just like their living relatives, the birds, and many reptiles. Eggs let a mother lay several babies at once and keep them safe in a nest until they hatch. Fos https://socialmedia.xdme.com/tony/videos-book2/page-008.mp4 https://www.youtube.com/embed/qvruenk3WPk 118 2026-09-29T15:20:27+00:00 yes https://xdme.com/watch-book5-q009.html https://xdme.com/book5-thumbs/page-009.jpg Stomp Stomp! Why Do We Find Dinosaur Footprints? A dinosaur footprint can form when a dinosaur walks over soft mud or sand. If that print dries, gets covered, and slowly turns to rock, it can last for millions of years. Trails of https://socialmedia.xdme.com/tony/videos-book2/page-009.mp4 https://www.youtube.com/embed/6BS1S9AkbsE 127 2026-09-29T14:50:27+00:00 yes https://xdme.com/watch-book5-q010.html https://xdme.com/book5-thumbs/page-010.jpg Dino Crowds! Why Did Some Dinosaurs Live in Herds? Fossil trails with many footprints side by side suggest that some dinosaurs traveled together. Living in a group may have helped animals spot danger and protect their young. Scient https://socialmedia.xdme.com/tony/videos-book2/page-010.mp4 https://www.youtube.com/embed/Khpjn5s_Cb8 115 2026-09-29T14:57:30+00:00 yes https://xdme.com/watch-book5-q011.html https://xdme.com/book5-thumbs/page-011.jpg Chomp! Why Did Meat-Eating Dinosaurs Have Sharp Teeth? Meat-eating dinosaurs had teeth shaped for biting and tearing flesh. Some teeth were pointed, and some had tiny ridges along the edge, a bit like a steak knife. A tooth can tell sc https://socialmedia.xdme.com/tony/videos-book2/page-011.mp4 https://www.youtube.com/embed/VyrknDuqj2U 123 2026-09-29T14:56:59+00:00 yes https://xdme.com/watch-book5-q012.html https://xdme.com/book5-thumbs/page-012.jpg Munch Munch! Why Did Plant-Eaters Have Beaks or Grinders? Plants can be tough to eat, so plant-eating dinosaurs had special tools. Some had beaks for snipping leaves and stems. Others had lots of flat teeth for grinding plants into smalle https://socialmedia.xdme.com/tony/videos-book2/page-012.mp4 https://www.youtube.com/embed/Wd25IobVQRA 115 2026-09-29T15:11:03+00:00 yes https://xdme.com/watch-book5-q013.html https://xdme.com/book5-thumbs/page-013.jpg Wings Over Dinos! Why Did Flying Reptiles Soar? Pterosaurs were flying reptiles that lived at the same time as the dinosaurs, though they were not dinosaurs themselves. Their wings were made of skin stretched from a very long fi https://socialmedia.xdme.com/tony/videos-book2/page-013.mp4 https://www.youtube.com/embed/J4EKT_zn4TA 123 2026-09-29T15:18:06+00:00 yes https://xdme.com/watch-book5-q014.html https://xdme.com/book5-thumbs/page-014.jpg Sea Monsters? Why Were There Giant Sea Reptiles Too? While dinosaurs walked on land, big reptiles like ichthyosaurs and plesiosaurs swam in the oceans. They were not dinosaurs, but they lived at the same time. The seas were full of f https://socialmedia.xdme.com/tony/videos-book2/page-014.mp4 https://www.youtube.com/embed/Q9IdsBKBsh4 116 2026-09-29T15:18:06+00:00 yes https://xdme.com/watch-book5-q015.html https://xdme.com/book5-thumbs/page-015.jpg Hungry Giants! Why Did Dinosaurs Need So Much Food? A big body needs a lot of energy to move and grow. Giant plant-eating dinosaurs probably spent much of their day eating, because leaves do not have much energy in each bite. That i https://socialmedia.xdme.com/tony/videos-book2/page-015.mp4 https://www.youtube.com/embed/jPWzpNJz1xY 122 2026-09-29T22:34:19+00:00 yes https://xdme.com/watch-book5-q016.html https://xdme.com/book5-thumbs/page-016.jpg Oops, Wrong Colors? Why Do Movies Get Dinosaurs Wrong? Most fossils show bones and not colors, so movie makers have to guess how dinosaurs looked. A few rare fossils keep tiny clues about color, and scientists are learning to read them https://socialmedia.xdme.com/tony/videos-book2/page-016.mp4 https://www.youtube.com/embed/5N_cZ6PtWSU 123 2026-09-29T16:16:30+00:00 yes https://xdme.com/watch-book5-q017.html https://xdme.com/book5-thumbs/page-017.jpg Cool Crests! Why Did Some Dinosaurs Have Crests and Sails? Some dinosaurs had crests on their heads or tall sails on their backs. Scientists think they may have been used for showing off and for recognizing others of the same kind. Some cr https://socialmedia.xdme.com/tony/videos-book2/page-017.mp4 https://www.youtube.com/embed/Z6d9UoFyITw 118 2026-09-29T16:28:34+00:00 yes https://xdme.com/watch-book5-q018.html https://xdme.com/book5-thumbs/page-018.jpg Fast or Slow? Why Do Scientists Argue About T. Rex Speed? Nobody could time a Tyrannosaurus rex, so scientists use clues like leg bones, footprints, and computer models. Different methods give different answers, and that leads to friendly https://socialmedia.xdme.com/tony/videos-book2/page-018.mp4 https://www.youtube.com/embed/G2nblHxqK-o 118 2026-09-29T15:58:56+00:00 yes https://xdme.com/watch-book5-q019.html https://xdme.com/book5-thumbs/page-019.jpg Not Mini Adults! Why Were Baby Dinosaurs Different? Young dinosaurs did not always look like small copies of their parents. Fossils of babies and teenagers show that their bodies could have different shapes, and some features change https://socialmedia.xdme.com/tony/videos-book2/page-019.mp4 https://www.youtube.com/embed/7W0w9dFSabA 122 2026-09-29T16:15:59+00:00 yes https://xdme.com/watch-book5-q020.html https://xdme.com/book5-thumbs/page-020.jpg Worldwide Dinos! Why Did Dinosaurs Live Almost Everywhere? Dinosaurs lived for well over 150 million years, which gave them lots of time to spread out. Their fossils have been found on every continent, even Antarctica. Earth's land has slo https://socialmedia.xdme.com/tony/videos-book2/page-020.mp4 https://www.youtube.com/embed/_JG_ErxsEpM 131 2026-09-29T18:04:22+00:00 yes https://xdme.com/watch-book5-q021.html https://xdme.com/book5-thumbs/page-021.jpg Cluck Cluck! Why Is a Chicken a Clue About Dinosaurs? Birds, including chickens, are living relatives of the dinosaurs. They have feathers, lay eggs, and have leg bones that look a lot like some dinosaurs' legs. Scientists compare bir https://socialmedia.xdme.com/tony/videos-book2/page-021.mp4 https://www.youtube.com/embed/1e2RbJT7yLs 122 2026-09-29T18:30:36+00:00 yes https://xdme.com/watch-book5-q022.html https://xdme.com/book5-thumbs/page-022.jpg So Many Dinos! Why Did So Many Kinds Exist? Dinosaurs lived for a very long time, and during those millions of years, the world changed. As places and plants changed, new kinds of dinosaurs appeared to fit new homes and food https://socialmedia.xdme.com/tony/videos-book2/page-022.mp4 https://www.youtube.com/embed/BRfTzCMJ1Mg 120 2026-09-29T19:00:46+00:00 yes https://xdme.com/watch-book5-q023.html https://xdme.com/book5-thumbs/page-023.jpg No Fresh Dino Meat? Here's Why We Never Find It! Dinosaurs lived millions of years ago, and soft parts like meat rot away long before that much time passes. What we usually find are hard parts like bones and teeth, which slowly t https://socialmedia.xdme.com/tony/videos-book2/page-023.mp4 https://www.youtube.com/embed/wd2Ykiyh9gA 120 2026-09-29T18:59:15+00:00 yes https://xdme.com/watch-book5-q024.html https://xdme.com/book5-thumbs/page-024.jpg The Big Goodbye! Why Did Non-Bird Dinosaurs Disappear? About 66 million years ago, a huge space rock hit Earth, and big volcanic eruptions were happening around the same time. Earth's climate changed, and the dinosaurs that were not bi https://socialmedia.xdme.com/tony/videos-book2/page-024.mp4 https://www.youtube.com/embed/YinZxJicNmU 124 2026-09-29T19:26:51+00:00 yes https://xdme.com/watch-book5-q025.html https://xdme.com/book5-thumbs/page-025.jpg Be a Dino Detective! How Do We Think Like One? Dinosaur detectives look closely at clues like bones, teeth, and footprints. They ask questions, compare what they find with living animals, and make a careful guess. Then they cha https://socialmedia.xdme.com/tony/videos-book2/page-025.mp4 https://www.youtube.com/embed/iGSGGwamfaM 117 2026-09-29T19:26:52+00:00 yes https://xdme.com/watch-book5-q026.html https://xdme.com/book5-thumbs/page-026.jpg Bone to Stone! Why Does a Bone Turn Into a Fossil? When an animal's bones get buried quickly, water with minerals can slowly seep into them. Over a very long time, the minerals fill and harden the bone until it becomes rock-like. T https://socialmedia.xdme.com/tony/videos-book2/page-026.mp4 https://www.youtube.com/embed/bqsb46CUJ1c 121 2026-09-29T19:36:53+00:00 yes https://xdme.com/watch-book5-q027.html https://xdme.com/book5-thumbs/page-027.jpg Layer Cake Earth! Why Are Fossils Found in Rock Layers? Mud, sand, and tiny bits of rock settle in layers, and those layers can harden into rock. An animal buried in a layer may become a fossil, which is why fossils are found in this ki https://socialmedia.xdme.com/tony/videos-book2/page-027.mp4 https://www.youtube.com/embed/PNC3mNcllAc 115 2026-09-29T19:45:55+00:00 yes https://xdme.com/watch-book5-q028.html https://xdme.com/book5-thumbs/page-028.jpg Dig Detectives! Why Use Brushes Instead of Shovels? Fossils can be fragile, and a shovel could crack or crush them. Scientists use soft brushes and small tools to clear away dirt very gently. Slow and careful digging helps protect t https://socialmedia.xdme.com/tony/videos-book2/page-028.mp4 https://www.youtube.com/embed/a5N2E3yEsYI 122 2026-09-29T19:56:29+00:00 yes https://xdme.com/watch-book5-q029.html https://xdme.com/book5-thumbs/page-029.jpg Cast for a Bone! Why Make a Plaster Jacket? A plaster jacket is a hard wrapping made with strips of cloth and plaster. It works a bit like a cast on a broken arm, keeping a fragile fossil safe while it is carried from the di https://socialmedia.xdme.com/tony/videos-book2/page-029.mp4 https://www.youtube.com/embed/VwtQNiUbRFo 120 2026-09-29T19:55:58+00:00 yes https://xdme.com/watch-book5-q030.html https://xdme.com/book5-thumbs/page-030.jpg Missing Pieces! Why Are Most Fossils Not Whole Skeletons? When an animal dies, its body can be eaten, broken, or washed away before it is buried. Only some parts end up in the right place to become fossils. That is why scientists usually https://socialmedia.xdme.com/tony/videos-book2/page-030.mp4 https://www.youtube.com/embed/yATapFcTH3g 118 2026-09-29T20:17:06+00:00 yes https://xdme.com/watch-book5-q031.html https://xdme.com/book5-thumbs/page-031.jpg Squished Fossils? Why Do Some Look Smashed or Stretched? Fossils sit inside rock for millions of years, with heavy layers pressing down on them. Pressure and slow movements of the ground can squash, bend, or stretch them. Scientists have https://socialmedia.xdme.com/tony/videos-book2/page-031.mp4 https://www.youtube.com/embed/3bTXtEYY2Vk 121 2026-09-29T20:16:05+00:00 yes https://xdme.com/watch-book5-q032.html https://xdme.com/book5-thumbs/page-032.jpg Tooth Talk! How Can a Tooth Tell What an Animal Ate? Teeth come in different shapes for different foods. Sharp, pointed teeth are good for tearing meat, while flat teeth are good for grinding plants. Scientists can also look at wear https://socialmedia.xdme.com/tony/videos-book2/page-032.mp4 https://www.youtube.com/embed/02BrdQLgn6I 118 2026-09-29T20:26:12+00:00 yes https://xdme.com/watch-book5-q033.html https://xdme.com/book5-thumbs/page-033.jpg Leaf Prints! Why Do We Find Fossils of Leaves and Wood? Plants can become fossils too. A leaf can leave a print in soft mud, and buried wood can slowly turn to stone as minerals fill it. Plant fossils give clues about what ancient place https://socialmedia.xdme.com/tony/videos-book2/page-033.mp4 https://www.youtube.com/embed/oppC74hd_Y0 120 2026-09-29T20:26:13+00:00 yes https://xdme.com/watch-book5-q034.html https://xdme.com/book5-thumbs/page-034.jpg Time Capsule in Gold! Why Is Amber So Special? Amber is hardened tree resin, a sticky sap that slowly turned solid over a very long time. Sometimes a tiny insect or spider got stuck in the resin before it hardened. Inside amber https://socialmedia.xdme.com/tony/videos-book2/page-034.mp4 https://www.youtube.com/embed/KzSbumE5O3w 120 2026-09-29T20:35:44+00:00 yes https://xdme.com/watch-book5-q035.html https://xdme.com/book5-thumbs/page-035.jpg Leave It There! Why Not Pocket a Fossil From a Park? Many parks have rules against taking fossils home, and it is important to follow them. Where a fossil is found is an important clue, and moving it can lose that clue. The best plan https://socialmedia.xdme.com/tony/videos-book2/page-035.mp4 https://www.youtube.com/embed/PgitVg7Y8aE 116 2026-09-29T20:35:45+00:00 yes https://xdme.com/watch-book5-q036.html https://xdme.com/book5-thumbs/page-036.jpg Copycat Bones! Why Do Museums Use Casts? A cast is a copy of a real fossil bone. Real fossils can be heavy, fragile, and hard to replace, so museums often build displays with casts. The real bones stay safe for scientists https://socialmedia.xdme.com/tony/videos-book2/page-036.mp4 https://www.youtube.com/embed/OHyfnTobqtw 116 2026-09-29T21:07:23+00:00 yes https://xdme.com/watch-book5-q037.html https://xdme.com/book5-thumbs/page-037.jpg Follow the River! Why Do Old River Maps Help Fossil Hunters? Rivers can carry and bury animals and plants in sand and mud. Maps of old river channels in rock can hint at where good fossil-hunting spots might be. Fossil hunters use maps as cl https://socialmedia.xdme.com/tony/videos-book2/page-037.mp4 https://www.youtube.com/embed/gNgbTqoQXgI 117 2026-09-29T21:06:43+00:00 yes https://xdme.com/watch-book5-q038.html https://xdme.com/book5-thumbs/page-038.jpg Fossil Travelers! Why the Same Fossil on Two Continents? The continents have slowly moved over millions of years, so they were not always where they are now. Some lands that are far apart today were once connected or closer together, and https://socialmedia.xdme.com/tony/videos-book2/page-038.mp4 https://www.youtube.com/embed/miwjc4t5-8M 118 2026-09-29T21:17:24+00:00 yes https://xdme.com/watch-book5-q039.html https://xdme.com/book5-thumbs/page-039.jpg Snap and Label! Why Number and Photograph Every Find? Scientists write a number on each find and take photos to record exactly where it was found. That way nothing gets mixed up, and the clues about where it came from are saved. Good https://socialmedia.xdme.com/tony/videos-book2/page-039.mp4 https://www.youtube.com/embed/vym0yWP3kbs 120 2026-09-29T15:20:28+00:00 yes https://xdme.com/watch-book5-q040.html https://xdme.com/book5-thumbs/page-040.jpg Yes, Really! Why Can Coprolites Be Useful? Coprolites are fossilized poop! They can hold bits of bone, plants, or other leftovers of a meal. That gives scientists clues about what an animal ate long ago. https://socialmedia.xdme.com/tony/videos-book2/page-040.mp4 https://www.youtube.com/embed/jqdYDbRnnTs 126 2026-09-29T15:20:29+00:00 yes https://xdme.com/watch-book5-q041.html https://xdme.com/book5-thumbs/page-041.jpg Follow the Trail! Why Do Trackways Count as Fossils? Fossils are not only bones. Footprints, trails, and burrows preserved in rock are called trace fossils. Trackways show how animals moved and behaved, which bones alone cannot alway https://socialmedia.xdme.com/tony/videos-book2/page-041.mp4 https://www.youtube.com/embed/qASzdmljj7o 120 2026-09-29T15:20:30+00:00 yes https://xdme.com/watch-book5-q042.html https://xdme.com/book5-thumbs/page-042.jpg Save Some for Later! Why Leave a Dig Site Half-Buried? Sometimes scientists choose not to dig everything up at once. Leaving part of a site in the ground can protect it, and future scientists with new tools and new questions may learn https://socialmedia.xdme.com/tony/videos-book2/page-042.mp4 https://www.youtube.com/embed/n3FoLmk1Eds 134 2026-09-29T14:50:28+00:00 yes https://xdme.com/watch-book5-q043.html https://xdme.com/book5-thumbs/page-043.jpg Sparkly Stone! Why Do Some Fossils Sparkle or Change Color? When a bone or shell becomes a fossil, minerals can slowly replace or fill the original material. Different minerals can add different colors, and some can sparkle. That is why som https://socialmedia.xdme.com/tony/videos-book2/page-043.mp4 https://www.youtube.com/embed/am9_XcvSM_M 129 2026-09-29T15:04:31+00:00 yes https://xdme.com/watch-book5-q044.html https://xdme.com/book5-thumbs/page-044.jpg Rock Clock Clues! Why Is Index Fossil a Useful Nickname? An index fossil comes from a kind of living thing that was common and lived only during a certain stretch of time. If scientists find that fossil in a rock layer, it gives a clue a https://socialmedia.xdme.com/tony/videos-book2/page-044.mp4 https://www.youtube.com/embed/zk3ldh2KEig 123 2026-09-29T15:04:32+00:00 yes https://xdme.com/watch-book5-q045.html https://xdme.com/book5-thumbs/page-045.jpg Tiny Tools! Why Do Labs Use Tiny Saws and Needles? Fossils can be delicate, so lab workers clean off rock with very small tools like fine needles and tiny saws. They often work under a microscope. Slow, careful work helps protect e https://socialmedia.xdme.com/tony/videos-book2/page-045.mp4 https://www.youtube.com/embed/pWYIx_Lh8bw 124 2026-09-29T15:25:19+00:00 yes https://xdme.com/watch-book5-q046.html https://xdme.com/book5-thumbs/page-046.jpg X-Ray Vision! Why Do CT Scans Help With Fossils? A CT scan takes many X-ray pictures from different angles and turns them into a 3D view. Scientists can look inside a fossil without cutting the rock open. It is a great way to see https://socialmedia.xdme.com/tony/videos-book2/page-046.mp4 https://www.youtube.com/embed/_lohtcnN53Q 124 2026-09-29T15:24:48+00:00 yes https://xdme.com/watch-book5-q047.html https://xdme.com/book5-thumbs/page-047.jpg Number One Fossil! Why Is a Holotype Extra Important? A holotype is the specimen scientists use to officially describe and name a new species. Later scientists can compare new finds with it. It works like a reference example that help https://socialmedia.xdme.com/tony/videos-book2/page-047.mp4 https://www.youtube.com/embed/mH2FODZY1yc 114 2026-09-29T15:39:51+00:00 yes https://xdme.com/watch-book5-q048.html https://xdme.com/book5-thumbs/page-048.jpg Name Change! Why Do Dinosaur Names Sometimes Change? When scientists learn something new, they may update names. A newer fossil might show that two names were really for the same animal, or that an animal belongs in a different group https://socialmedia.xdme.com/tony/videos-book2/page-048.mp4 https://www.youtube.com/embed/HxHtlcjRRoo 125 2026-09-29T15:40:22+00:00 yes https://xdme.com/watch-book5-q049.html https://xdme.com/book5-thumbs/page-049.jpg Still Digging! Why Do We Find New Fossils Every Year? There are so many places on Earth that have not been searched carefully yet. Wind, water, and weather can uncover fossils that were hidden for millions of years. Better tools and l https://socialmedia.xdme.com/tony/videos-book2/page-049.mp4 https://www.youtube.com/embed/xrk8HIuIud4 118 2026-09-29T15:57:54+00:00 yes https://xdme.com/watch-book5-q050.html https://xdme.com/book5-thumbs/page-050.jpg Fossil Detective Mode! How Do We Think Like One? A fossil detective looks closely, measures, and compares clues. They ask what is missing, and they are careful about making big claims. When they find something new, they are ready https://socialmedia.xdme.com/tony/videos-book2/page-050.mp4 https://www.youtube.com/embed/px7x-Sy-5Tc 113 2026-09-30T00:36:54+00:00 yes https://xdme.com/watch-book5-q051.html https://xdme.com/book5-thumbs/page-051.jpg Ice Sculptors! Why Does Ice Carve Valleys? A glacier is a huge, slow-moving river of ice. As it creeps downhill, it drags rocks along the bottom and scrapes and carves the land beneath it. Over thousands of years, that can https://socialmedia.xdme.com/tony/videos-book2/page-051.mp4 https://www.youtube.com/embed/7oUrd7TAkLI 129 2026-09-29T17:55:21+00:00 yes https://xdme.com/watch-book5-q052.html https://xdme.com/book5-thumbs/page-052.jpg Scratch Marks! Why Do Glaciers Scratch the Rock? Glaciers carry rocks and gravel frozen into the bottom of the ice. When the glacier moves, those stones scrape across bedrock like sandpaper and leave long scratches called striati https://socialmedia.xdme.com/tony/videos-book2/page-052.mp4 https://www.youtube.com/embed/U5fiohOMgjM 123 2026-09-29T17:54:49+00:00 yes https://xdme.com/watch-book5-q053.html https://xdme.com/book5-thumbs/page-053.jpg Ice Age Leftovers! Why Are Some Lakes Left by Ice? During the ice ages, glaciers dug out hollows in the ground as they moved. When the ice melted, water filled many of those hollows and made lakes. Some lakes we see today started t https://socialmedia.xdme.com/tony/videos-book2/page-053.mp4 https://www.youtube.com/embed/KDNSQ_HQO6k 119 2026-09-29T18:04:23+00:00 yes https://xdme.com/watch-book5-q054.html https://xdme.com/book5-thumbs/page-054.jpg Mountain Maker! Why Does a Volcano Make a Mountain? A volcano forms when melted rock from inside Earth pushes up through the surface. Each eruption spreads lava and ash, and over time, layer after layer builds up into a mountain. So https://socialmedia.xdme.com/tony/videos-book2/page-054.mp4 https://www.youtube.com/embed/y10W4rJqLQE 130 2026-09-29T18:26:05+00:00 yes https://xdme.com/watch-book5-q055.html https://xdme.com/book5-thumbs/page-055.jpg Hot Rock Mix-Up! Why Is Lava Different From Magma? Magma is melted rock that is still underground. When it erupts and flows out onto the surface, it is called lava. Same hot rock, different name depending on where it is! https://socialmedia.xdme.com/tony/videos-book2/page-055.mp4 https://www.youtube.com/embed/veGKVj_1ZY0 129 2026-09-29T19:36:54+00:00 yes https://xdme.com/watch-book5-q056.html https://xdme.com/book5-thumbs/page-056.jpg Boom or Ooze? Why Do Some Volcanoes Explode? Some volcanoes have thick, sticky magma that traps gas, and pressure can build until the volcano erupts with a blast. Other volcanoes have runnier magma that lets gas escape, so la https://socialmedia.xdme.com/tony/videos-book2/page-056.mp4 https://www.youtube.com/embed/7mFM81xiIoo 126 2026-09-29T19:45:56+00:00 yes https://xdme.com/watch-book5-q057.html https://xdme.com/book5-thumbs/page-057.jpg Friend and Foe! Why Is Volcanic Ash Dangerous and Useful? Volcanic ash is made of tiny, sharp bits of rock and glass, so it can be hard to breathe in and can damage machines. Over time, though, ash breaks down and adds minerals to soil th https://socialmedia.xdme.com/tony/videos-book2/page-057.mp4 https://www.youtube.com/embed/NdKLAYpQimY 127 2026-09-29T20:06:31+00:00 yes https://xdme.com/watch-book5-q058.html https://xdme.com/book5-thumbs/page-058.jpg Steamy Surprise! Why Do Hot Springs and Geysers Exist? In some places, water seeps down into the ground and gets heated by hot rock deep below. That hot water can rise back up as a hot spring. In a geyser, the heated water and steam bu https://socialmedia.xdme.com/tony/videos-book2/page-058.mp4 https://www.youtube.com/embed/U8cCxTZRSWg 128 2026-09-29T20:07:32+00:00 yes https://xdme.com/watch-book5-q059.html https://xdme.com/book5-thumbs/page-059.jpg Shake, Rattle and Roll! Why Does Earth Have Earthquakes? Earth's outer layer is broken into big pieces called plates that move very slowly. Sometimes the edges get stuck, and then they suddenly slip. That sudden slip sends out shaking wa https://socialmedia.xdme.com/tony/videos-book2/page-059.mp4 https://www.youtube.com/embed/dZp6bRiVFBk 123 2026-09-29T20:46:16+00:00 yes https://xdme.com/watch-book5-q060.html https://xdme.com/book5-thumbs/page-060.jpg Slow Motion Puzzle! Why Do Earth's Plates Move? Earth's outer shell is made of huge plates that fit together a bit like puzzle pieces. They move very slowly, about as fast as your fingernails grow. Heat deep inside Earth helps d https://socialmedia.xdme.com/tony/videos-book2/page-060.mp4 https://www.youtube.com/embed/DRBww2tyR2o 129 2026-09-29T20:46:51+00:00 yes https://xdme.com/watch-book5-q061.html https://xdme.com/book5-thumbs/page-061.jpg Up, Up, Up! Why Do Mountains Rise? Some mountains rise when two of Earth's plates push against each other and the land crumples and lifts up. It takes millions of years. Some mountains are also built by volcanoes. https://socialmedia.xdme.com/tony/videos-book2/page-061.mp4 https://www.youtube.com/embed/Tr1Q6RR22pM 127 2026-09-29T20:57:30+00:00 yes https://xdme.com/watch-book5-q062.html https://xdme.com/book5-thumbs/page-062.jpg Deep Cuts! Why Do Canyons Get Deeper? Water flowing through a canyon slowly wears away rock and carries bits of it downstream. Over a very long time, the river cuts deeper and deeper. Wind and weather help wear the sid https://socialmedia.xdme.com/tony/videos-book2/page-062.mp4 https://www.youtube.com/embed/Nvo9yrMXEoA 125 2026-09-29T20:58:09+00:00 yes https://xdme.com/watch-book5-q063.html https://xdme.com/book5-thumbs/page-063.jpg Rock Breakers! Why Does Weather Break Rock? Rain gets into tiny cracks in rock. When that water freezes, it turns into ice and takes up more space, which pushes the crack wider. After many freezes and thaws, pieces of rock c https://socialmedia.xdme.com/tony/videos-book2/page-063.mp4 https://www.youtube.com/embed/-wROd6DdpkQ 123 2026-09-29T21:17:26+00:00 yes https://xdme.com/watch-book5-q064.html https://xdme.com/book5-thumbs/page-064.jpg Wiggle Wiggle! Why Do Rivers Curve? Water flows faster on the outside of a bend and wears away more of the bank there. On the inside of the bend, the water moves slower and drops sand and mud. Over time, these change https://socialmedia.xdme.com/tony/videos-book2/page-064.mp4 https://www.youtube.com/embed/K1JgV4P0RkQ 130 2026-09-29T21:39:03+00:00 yes https://xdme.com/watch-book5-q065.html https://xdme.com/book5-thumbs/page-065.jpg Backward Bound! Why Do Waterfalls Move Backward? Falling water can wear away the softer rock under a waterfall's edge. When the rock above loses support, it breaks off. Little by little, the waterfall moves upstream. https://socialmedia.xdme.com/tony/videos-book2/page-065.mp4 https://www.youtube.com/embed/CA8MjlwNJVA 130 2026-09-29T21:27:28+00:00 yes https://xdme.com/watch-book5-q066.html https://xdme.com/book5-thumbs/page-066.jpg More Than Mud! Why Is Soil More Than Dirt? Soil is a mix of tiny bits of rock, air, water, and rotted plant and animal material. It is also home to worms, insects, and lots of tiny living things. That mixture is what helps https://socialmedia.xdme.com/tony/videos-book2/page-066.mp4 https://www.youtube.com/embed/AfhV3c1-wHc 127 2026-09-29T21:27:29+00:00 yes https://xdme.com/watch-book5-q067.html https://xdme.com/book5-thumbs/page-067.jpg Dry Lands! Why Do Deserts Form? Deserts are places that get very little rain. Some form because of where they sit on Earth, and some are far from the sea or behind mountains that block rain. Not all deserts are h https://socialmedia.xdme.com/tony/videos-book2/page-067.mp4 https://www.youtube.com/embed/ohrOIwRyJdU 124 2026-09-29T21:38:32+00:00 yes https://xdme.com/watch-book5-q068.html https://xdme.com/book5-thumbs/page-068.jpg Always Wet! Why Do Rainforests Stay Wet? Rainforests get a lot of rain, and the warm air holds plenty of moisture. Trees also release water vapor from their leaves, which adds to the damp air. Thick leaves block sunlight https://socialmedia.xdme.com/tony/videos-book2/page-068.mp4 https://www.youtube.com/embed/4gpzT69s_1Q 133 2026-09-29T21:49:09+00:00 yes https://xdme.com/watch-book5-q069.html https://xdme.com/book5-thumbs/page-069.jpg Crack and Crumble! Another Look: How Weather Breaks Rock Rock is tough, but weather works on it slowly. Water, wind, heat, and cold can all wear it down, and even plant roots can push into cracks. Bit by bit, big rocks turn into smaller https://socialmedia.xdme.com/tony/videos-book2/page-069.mp4 https://www.youtube.com/embed/eY1QUU-cSqQ 119 2026-09-29T21:47:38+00:00 yes https://xdme.com/watch-book5-q070.html https://xdme.com/book5-thumbs/page-070.jpg Long Journey! Why Can a Pebble Travel So Far? Rivers, waves, and glaciers can pick up a pebble and carry it. As it tumbles along, it bumps against other rocks and gets smoother and smaller. Over time, a pebble can end up far f https://socialmedia.xdme.com/tony/videos-book2/page-070.mp4 https://www.youtube.com/embed/0K7HMDiSJbQ 119 2026-09-29T21:59:11+00:00 yes https://xdme.com/watch-book5-q071.html https://xdme.com/book5-thumbs/page-071.jpg Underground Worlds! Why Do Caves Form? Rainwater picks up a little acid from the air and soil. Where the rock is limestone, that slightly acidic water can slowly dissolve the rock and carve out empty spaces underground. https://socialmedia.xdme.com/tony/videos-book2/page-071.mp4 https://www.youtube.com/embed/tY0kVNP7Gnw 131 2026-09-29T21:58:40+00:00 yes https://xdme.com/watch-book5-q072.html https://xdme.com/book5-thumbs/page-072.jpg Old Ground, New Ground! Why Is Land Not the Same Age? Ground is being built and worn away all the time. Volcanoes make new rock, and rivers and weather wear old rock down. So some places have very old rock, and other places have much https://socialmedia.xdme.com/tony/videos-book2/page-072.mp4 https://www.youtube.com/embed/RxhQdu1jWcM 122 2026-09-29T22:08:42+00:00 yes https://xdme.com/watch-book5-q073.html https://xdme.com/book5-thumbs/page-073.jpg Frozen Time Capsules! Why Study Ice Cores? An ice core is a long tube of ice drilled from a glacier or ice sheet. It is made of layers of snow that built up year after year. Scientists study bubbles and other clues in the l https://socialmedia.xdme.com/tony/videos-book2/page-073.mp4 https://www.youtube.com/embed/Bf6-7u9U2G0 128 2026-09-29T22:09:13+00:00 yes https://xdme.com/watch-book5-q074.html https://xdme.com/book5-thumbs/page-074.jpg Handle With Care! Why Can a Changing Earth Be Dangerous? Earthquakes, volcanoes, floods, and landslides are all ways Earth changes, and they can be dangerous to people. Scientists watch for signs and study past events to help communities https://socialmedia.xdme.com/tony/videos-book2/page-074.mp4 https://www.youtube.com/embed/d_4gSlNnsnQ 120 2026-09-29T22:28:48+00:00 yes https://xdme.com/watch-book5-q075.html https://xdme.com/book5-thumbs/page-075.jpg Earth Detective Mode! How Do You Think Like One? An Earth detective looks for clues in rocks, layers, and landscapes. They ask what changed, how long it might have taken, and what could have caused it. Then they test their ideas, https://socialmedia.xdme.com/tony/videos-book2/page-075.mp4 https://www.youtube.com/embed/w6hIU-YZe8o 119 2026-09-29T22:19:14+00:00 yes https://xdme.com/watch-book5-q076.html https://xdme.com/book5-thumbs/page-076.jpg Stone Age Toolkit! Why Did Early People Make Stone Tools? Long ago, people did not have metal tools or stores. They shaped stones to cut, scrape, and pound, which helped with jobs like preparing food. Stone tools are some of the oldest cl https://socialmedia.xdme.com/tony/videos-book2/page-076.mp4 https://www.youtube.com/embed/KiXW6VzS3uk 126 2026-09-29T22:19:15+00:00 yes https://xdme.com/watch-book5-q077.html https://xdme.com/book5-thumbs/page-077.jpg Sharp Idea! Why Is a Sharp Flake a Big Invention? When a stone is struck the right way, a thin, sharp piece called a flake breaks off. A flake can cut like a simple knife. It was a clever way to make a useful tool from a plain roc https://socialmedia.xdme.com/tony/videos-book2/page-077.mp4 https://www.youtube.com/embed/McXJuJ7rqcY 126 2026-09-29T15:20:31+00:00 yes https://xdme.com/watch-book5-q078.html https://xdme.com/book5-thumbs/page-078.jpg Fire Power! Why Did Fire Change How People Lived? Fire gave people light, warmth, and a way to cook food. It could also help keep away some animals at night. A campfire also became a place for people to gather together. https://socialmedia.xdme.com/tony/videos-book2/page-078.mp4 https://www.youtube.com/embed/AVy-Hz506QU 130 2026-09-29T15:20:32+00:00 yes https://xdme.com/watch-book5-q079.html https://xdme.com/book5-thumbs/page-079.jpg Let's Cook! Why Did People Start Cooking Food? Cooking with fire changes food, and it can make some foods softer and easier to chew. Cooked food can also be safer to eat. Archaeologists look for old hearths, or fire spots, as c https://socialmedia.xdme.com/tony/videos-book2/page-079.mp4 https://www.youtube.com/embed/d4QHNRPqB-4 119 2026-09-29T15:20:33+00:00 yes https://xdme.com/watch-book5-q080.html https://xdme.com/book5-thumbs/page-080.jpg Ancient Fashion! Why Did People Wear Skins and Plant Fibers? People needed clothes to stay warm and protected, and they made them from what they could find. That included animal skins and fibers from plants. Tools like needles suggest that p https://socialmedia.xdme.com/tony/videos-book2/page-080.mp4 https://www.youtube.com/embed/aq0dwiBG1FM 123 2026-09-29T15:20:35+00:00 yes https://xdme.com/watch-book5-q081.html https://xdme.com/book5-thumbs/page-081.jpg Follow the Herd! Why Did People Follow Animal Herds? Animals like deer and bison moved from place to place to find fresh food. People who depended on hunting often moved along with them. Following the herds was a way to keep finding https://socialmedia.xdme.com/tony/videos-book2/page-081.mp4 https://www.youtube.com/embed/HSQz0feEKJ0 122 2026-09-29T15:20:36+00:00 yes https://xdme.com/watch-book5-q082.html https://xdme.com/book5-thumbs/page-082.jpg Cave Artists! Why Did People Paint on Cave Walls? People painted animals and shapes on cave walls thousands of years ago, and some of those paintings are still there today. Scientists are not sure exactly why they did it. The pain https://socialmedia.xdme.com/tony/videos-book2/page-082.mp4 https://www.youtube.com/embed/0CMUvlY_JPA 121 2026-09-29T15:20:36+00:00 yes https://xdme.com/watch-book5-q083.html https://xdme.com/book5-thumbs/page-083.jpg Hello From the Past! Why Are Handprints in Caves a Clue? Some caves have handprints that were made thousands of years ago. A handprint shows that a real person was there, and it can give hints about who made it. Scientists are careful to https://socialmedia.xdme.com/tony/videos-book2/page-083.mp4 https://www.youtube.com/embed/tZvTxQ9I3Gw 115 2026-09-29T19:08:48+00:00 yes https://xdme.com/watch-book5-q084.html https://xdme.com/book5-thumbs/page-084.jpg Home Sweet Home! Why Did People Start Staying in One Place? For a very long time, many people moved around to find food. Later, some groups began to settle in one place, especially where there was good food and water. Staying put made it ea https://socialmedia.xdme.com/tony/videos-book2/page-084.mp4 https://www.youtube.com/embed/TC9l0hix5_4 117 2026-09-29T18:14:59+00:00 yes https://xdme.com/watch-book5-q085.html https://xdme.com/book5-thumbs/page-085.jpg Seeds of Change! Why Did Farming Change Everything? Farming meant people could grow plants and raise animals instead of only searching for food. That let more people stay in one place and store food for later. Over time, villages gr https://socialmedia.xdme.com/tony/videos-book2/page-085.mp4 https://www.youtube.com/embed/BktqnxXhFPE 115 2026-09-29T23:41:19+00:00 yes https://xdme.com/watch-book5-q086.html https://xdme.com/book5-thumbs/page-086.jpg Best Friends Forever! Why Did People Domesticate Dogs? Dogs are descended from wolves, and they were probably the first animals people tamed. Over a very long time, some wolves that lived near people became friendlier and started to he https://socialmedia.xdme.com/tony/videos-book2/page-086.mp4 https://www.youtube.com/embed/vJ-aPJjAGrk 118 2026-09-30T00:11:05+00:00 yes https://xdme.com/watch-book5-q087.html https://xdme.com/book5-thumbs/page-087.jpg Grain Gains! Why Did People Grow Grain? Grains like wheat and barley have seeds that can be stored for a long time. Grown in fields, they gave people a steady supply of food. Grain could also be ground into flour, which https://socialmedia.xdme.com/tony/videos-book2/page-087.mp4 https://www.youtube.com/embed/jTcDE2nPlA4 112 2026-09-29T22:42:35+00:00 yes https://xdme.com/watch-book5-q088.html https://xdme.com/book5-thumbs/page-088.jpg Pots, Baskets, Big Deal! Why Did They Matter? Pots and baskets let people carry, store, and protect food and water. Clay pots could also be used for cooking. Broken pieces of pottery are important clues for archaeologists. https://socialmedia.xdme.com/tony/videos-book2/page-088.mp4 https://www.youtube.com/embed/5XamPYpUHaE 115 2026-09-29T23:04:10+00:00 yes https://xdme.com/watch-book5-q089.html https://xdme.com/book5-thumbs/page-089.jpg Stitch by Stitch! Why Did People Make Needles? A needle helps pull thread through skin or cloth, so people could sew pieces together into clothing. Very old needles have been found made from bone. Sewing helped people make warm https://socialmedia.xdme.com/tony/videos-book2/page-089.mp4 https://www.youtube.com/embed/Mdkg8VH4wOw 116 2026-09-29T23:22:14+00:00 yes https://xdme.com/watch-book5-q090.html https://xdme.com/book5-thumbs/page-090.jpg Buried Treasures? Why Bury Tools With the Dead? In some places, people placed tools and other objects in graves. Archaeologists think this could show care and respect, or beliefs about what people would need next. Nobody can be https://socialmedia.xdme.com/tony/videos-book2/page-090.mp4 https://www.youtube.com/embed/NjXEtaKk7jA 123 2026-09-29T23:41:50+00:00 yes https://xdme.com/watch-book5-q091.html https://xdme.com/book5-thumbs/page-091.jpg Camp by the Water! Why Do We Find Old Camps Near Water? People need water to drink, and water also brings plants and animals. That made spots near rivers and lakes very good places to camp. Archaeologists often find old campsites there. https://socialmedia.xdme.com/tony/videos-book2/page-091.mp4 https://www.youtube.com/embed/8v-QxQ2KYRQ 123 2026-09-29T23:03:09+00:00 yes https://xdme.com/watch-book5-q092.html https://xdme.com/book5-thumbs/page-092.jpg Colorful Clues! Why Did People Use Ochre? Ochre is a natural earth material that can be red or yellow. People used it to make paint, and it has been found at very old sites. Scientists think it might have been used for art https://socialmedia.xdme.com/tony/videos-book2/page-092.mp4 https://www.youtube.com/embed/HYZw2VRDN58 118 2026-09-30T00:28:17+00:00 yes https://xdme.com/watch-book5-q093.html https://xdme.com/book5-thumbs/page-093.jpg Row, Row! Why Did Boats Matter? Boats let people cross rivers, lakes, and seas to fish, travel, and trade. They opened up new places to explore. Boats help explain how people reached lands far away. https://socialmedia.xdme.com/tony/videos-book2/page-093.mp4 https://www.youtube.com/embed/-kqngNyorx4 115 2026-09-30T00:00:55+00:00 yes https://xdme.com/watch-book5-q094.html https://xdme.com/book5-thumbs/page-094.jpg Seashells Far From the Sea! Why Did People Trade Them? Shells found far from the ocean show that objects moved long distances. People may have traded or passed them along as jewelry or special items. A shell far from the sea is a clue https://socialmedia.xdme.com/tony/videos-book2/page-094.mp4 https://www.youtube.com/embed/gFEGZXxwCTw 115 2026-09-29T23:31:47+00:00 yes https://xdme.com/watch-book5-q095.html https://xdme.com/book5-thumbs/page-095.jpg Trash Talk! Why Is a Midden Useful? A midden is an old pile of leftover things people threw away, like shells and bones. To archaeologists, old trash is full of clues about what people ate and used. So a trash heap c https://socialmedia.xdme.com/tony/videos-book2/page-095.mp4 https://www.youtube.com/embed/OVM63uQ7f40 117 2026-09-29T22:52:07+00:00 yes https://xdme.com/watch-book5-q096.html https://xdme.com/book5-thumbs/page-096.jpg Great Minds Think Alike! Why Did Groups Invent Similar Tools? People in different places often had similar problems, like needing to cut, dig, or carry things. So they sometimes came up with similar solutions. Similar tools do not always mean https://socialmedia.xdme.com/tony/videos-book2/page-096.mp4 https://www.youtube.com/embed/mocD-4y7sF8 118 2026-09-29T22:47:06+00:00 yes https://xdme.com/watch-book5-q097.html https://xdme.com/book5-thumbs/page-097.jpg Show Respect! Why Treat Burial Sites With Respect? Burial sites are places where real people were laid to rest, and they matter to families and communities today. Archaeologists follow rules and work carefully, often with the desce https://socialmedia.xdme.com/tony/videos-book2/page-097.mp4 https://www.youtube.com/embed/iE64cJkrPrk 118 2026-09-29T23:12:11+00:00 yes https://xdme.com/watch-book5-q098.html https://xdme.com/book5-thumbs/page-098.jpg Look, Don't Touch! Why Use Replicas Instead of Real Artifacts? Old artifacts can be delicate, and lots of hands can wear them down. A replica is a copy that people can hold and study without harming the real thing. That way the original stays https://socialmedia.xdme.com/tony/videos-book2/page-098.mp4 https://www.youtube.com/embed/IhcvynuXM-k 119 2026-09-29T22:56:08+00:00 yes https://xdme.com/watch-book5-q099.html https://xdme.com/book5-thumbs/page-099.jpg Many Groups! Why Were First People Not One Single Tribe? Early people lived in many places around the world, and there were many different groups. Each group had its own way of living, shaped by where it lived. Scientists study clues to https://socialmedia.xdme.com/tony/videos-book2/page-099.mp4 https://www.youtube.com/embed/YuNk84nB0So 114 2026-09-29T23:50:52+00:00 yes https://xdme.com/watch-book5-q100.html https://xdme.com/book5-thumbs/page-100.jpg History Detective Mode! How Do You Think Like One? A history detective looks closely at clues like tools, campfires, and paintings. They ask questions, compare what they find, and try not to jump to conclusions. Then they update th https://socialmedia.xdme.com/tony/videos-book2/page-100.mp4 https://www.youtube.com/embed/LWY3z_ILkw0 115 2026-09-30T00:01:55+00:00 yes https://xdme.com/watch-book5-q101.html https://xdme.com/book5-thumbs/page-101.jpg More Clues, Better Answers! Why Use More Than One Clue? One clue can be misleading, but several clues that agree make an idea stronger. Scientists compare fossils, rocks, tools, and measurements. When different kinds of evidence point t https://socialmedia.xdme.com/tony/videos-book2/page-101.mp4 https://www.youtube.com/embed/luK9Y3K05EA 122 2026-09-30T02:12:37+00:00 yes https://xdme.com/watch-book5-q102.html https://xdme.com/book5-thumbs/page-102.jpg It's Okay Not to Know! Is "We Don't Know Yet" an Answer? Yes! Saying "we don't know yet" is an honest answer in science. It tells everyone that there is more to find out. Many great discoveries began when someone admitted they did not kn https://socialmedia.xdme.com/tony/videos-book2/page-102.mp4 https://www.youtube.com/embed/hQPD8EOpIBs 124 2026-09-30T02:18:38+00:00 yes https://xdme.com/watch-book5-q103.html https://xdme.com/book5-thumbs/page-103.jpg Mind Changers! Why Do Scientists Change Their Minds? Scientists follow the evidence. If a new discovery or a better test shows something different, they update their ideas. Changing your mind because of good evidence is a strength in https://socialmedia.xdme.com/tony/videos-book2/page-103.mp4 https://www.youtube.com/embed/MYavwbApnig 115 2026-09-30T00:08:34+00:00 yes https://xdme.com/watch-book5-q104.html https://xdme.com/book5-thumbs/page-104.jpg Half a Skeleton? Why Is a Fossil Not Always Whole? Fossils often have missing pieces because most of an animal's body does not survive to become a fossil. Scientists use the parts they have and compare them with related animals. Th https://socialmedia.xdme.com/tony/videos-book2/page-104.mp4 https://www.youtube.com/embed/ruPueQQo8CE 123 2026-09-29T23:51:53+00:00 yes https://xdme.com/watch-book5-q105.html https://xdme.com/book5-thumbs/page-105.jpg Copies Help! Why Do Museums Use Casts? Casts are copies of real fossils, and they can be sturdy, easier to move, and shared with many museums. The real fossils can stay safe for scientists to study. Casts let more peopl https://socialmedia.xdme.com/tony/videos-book2/page-105.mp4 https://www.youtube.com/embed/HcToOUFwdxM 122 2026-09-30T00:26:16+00:00 yes https://xdme.com/watch-book5-q106.html https://xdme.com/book5-thumbs/page-106.jpg Dating Rocks! Why Date the Rock Around a Fossil? Fossils often cannot be dated directly, but the rock layers around them may hold clues. By working out the age of nearby rock, scientists can figure out about how old the fossil is https://socialmedia.xdme.com/tony/videos-book2/page-106.mp4 https://www.youtube.com/embed/bMymD_N2rvE 117 2026-09-29T22:37:27+00:00 yes https://xdme.com/watch-book5-q107.html https://xdme.com/book5-thumbs/page-107.jpg Label It! Why Are Indexes and Catalogs Useful? Scientists collect so many finds that they need a way to keep track of them. An index or catalog is like a list that tells where to find each item and what is known about it. It he https://socialmedia.xdme.com/tony/videos-book2/page-107.mp4 https://www.youtube.com/embed/3MgQD9-r9Gk 113 2026-09-30T00:17:06+00:00 yes https://xdme.com/watch-book5-q108.html https://xdme.com/book5-thumbs/page-108.jpg Sharing Is Caring! Why Do Scientists Share Their Finds? When scientists share what they find, others can check the work and add new ideas. Sharing helps everyone learn more than one person could alone. Science grows when people work tog https://socialmedia.xdme.com/tony/videos-book2/page-108.mp4 https://www.youtube.com/embed/uY6p7g7tWF8 111 2026-09-29T23:13:13+00:00 yes https://xdme.com/watch-book5-q109.html https://xdme.com/book5-thumbs/page-109.jpg Sketch It! Why Is a Drawing Useful in a Photo World? A photo shows everything, but a drawing can highlight the important parts. Scientists draw fossils and objects to point out details that might be hard to see. Drawing also makes yo https://socialmedia.xdme.com/tony/videos-book2/page-109.mp4 https://www.youtube.com/embed/FIcmVNqkcLE 106 2026-09-29T23:31:16+00:00 yes https://xdme.com/watch-book5-q110.html https://xdme.com/book5-thumbs/page-110.jpg Measure Up! Why Measure Instead of Just Looking? Numbers let scientists compare things exactly and tell others what they found. Two people might describe a bone as big, but a measurement is clearer. Measuring helps make results e https://socialmedia.xdme.com/tony/videos-book2/page-110.mp4 https://www.youtube.com/embed/iGCB9CaMuSk 109 2026-09-29T23:22:15+00:00 yes https://xdme.com/watch-book5-q111.html https://xdme.com/book5-thumbs/page-111.jpg Just a Pinch! Why Do Scientists Take Tiny Samples? Some tests need only a very small piece of a fossil or object. Taking a tiny sample helps protect the rest of it. Scientists also plan carefully so that they get as much informatio https://socialmedia.xdme.com/tony/videos-book2/page-111.mp4 https://www.youtube.com/embed/xgPERF3FfcQ 125 2026-09-30T02:25:39+00:00 yes https://xdme.com/watch-book5-q112.html https://xdme.com/book5-thumbs/page-112.jpg Friendly Disagreement! Why Can Two Teams Disagree? Two teams can look at the same evidence and come up with different ideas. They might have used different methods or asked different questions. Testing the ideas and finding more ev https://socialmedia.xdme.com/tony/videos-book2/page-112.mp4 https://www.youtube.com/embed/scqvxidv7P4 110 2026-09-30T00:19:44+00:00 yes https://xdme.com/watch-book5-q113.html https://xdme.com/book5-thumbs/page-113.jpg Double Check! Why Is Peer Review a Filter? In peer review, other experts read a scientist's work before it is published. They look for mistakes, missing evidence, and unclear ideas. It helps make sure that published science https://socialmedia.xdme.com/tony/videos-book2/page-113.mp4 https://www.youtube.com/embed/z1oMQhy3Eb4 111 2026-09-30T00:35:48+00:00 yes https://xdme.com/watch-book5-q114.html https://xdme.com/book5-thumbs/page-114.jpg Back to the Dig! Why Return to the Same Site? A site can hold more clues than scientists can uncover in one visit. Coming back lets them dig more, ask new questions, and use new tools. Every visit can add to the story. https://socialmedia.xdme.com/tony/videos-book2/page-114.mp4 https://www.youtube.com/embed/xEZit7hcKNk 123 2026-09-29T15:20:37+00:00 yes https://xdme.com/watch-book5-q115.html https://xdme.com/book5-thumbs/page-115.jpg Where It Was Found Matters! Why Is Context So Important? Context means where and how an object was found, and what was around it. The same object can tell a very different story depending on where it was. That is why scientists record th https://socialmedia.xdme.com/tony/videos-book2/page-115.mp4 https://www.youtube.com/embed/FFJiZCixcy8 120 2026-09-29T15:20:39+00:00 yes https://xdme.com/watch-book5-q116.html https://xdme.com/book5-thumbs/page-116.jpg X Marks the Spot! Why Do Maps of Finds Matter? A map of where things were found can show patterns. Scientists can see which finds were near each other and where to look next. Maps also help others understand a site later. https://socialmedia.xdme.com/tony/videos-book2/page-116.mp4 https://www.youtube.com/embed/p3JOf3xfMZg 121 2026-09-29T15:20:40+00:00 yes https://xdme.com/watch-book5-q117.html https://xdme.com/book5-thumbs/page-117.jpg One Tooth Tells All? Why Can a Single Tooth Be Enough? Teeth are hard and often last a long time as fossils. Their shape can hint at what an animal ate and what group it belongs to. Sometimes one tooth is enough to show scientists a ne https://socialmedia.xdme.com/tony/videos-book2/page-117.mp4 https://www.youtube.com/embed/Ts7bgsEPevo 119 2026-09-29T15:20:41+00:00 yes https://xdme.com/watch-book5-q118.html https://xdme.com/book5-thumbs/page-118.jpg Tiny Details! Why Use Microscopes on Old Dirt? Old dirt can hold very small clues like tiny seeds, pollen, bits of bone, and pieces of charcoal. A microscope helps scientists see them. Those little bits can show what people ate https://socialmedia.xdme.com/tony/videos-book2/page-118.mp4 https://www.youtube.com/embed/KhKpUajtM4A 119 2026-09-29T15:20:42+00:00 yes https://xdme.com/watch-book5-q119.html https://xdme.com/book5-thumbs/page-119.jpg Famous Fossil? Why It's Not the Whole Story! A famous fossil is exciting, but it is still only one animal from one moment in time. Scientists need many finds to learn how animals of that kind were alike and different. More fo https://socialmedia.xdme.com/tony/videos-book2/page-119.mp4 https://www.youtube.com/embed/pf__IpvPMso 120 2026-09-29T15:20:43+00:00 yes https://xdme.com/watch-book5-q120.html https://xdme.com/book5-thumbs/page-120.jpg Team Earth! Why Work With Local Communities? People who live near a site often know its history and care about its future. Scientists work with them to share knowledge, ask permission, and protect places. Working together is https://socialmedia.xdme.com/tony/videos-book2/page-120.mp4 https://www.youtube.com/embed/7Cuj1RxuEQU 118 2026-09-29T15:20:45+00:00 yes https://xdme.com/watch-book5-q121.html https://xdme.com/book5-thumbs/page-121.jpg Keep Out? Why Are Some Sites Closed to the Public? Some sites are fragile, and lots of visitors could damage them. Others are dangerous or still being studied. Closing a site can protect the clues for the future. https://socialmedia.xdme.com/tony/videos-book2/page-121.mp4 https://www.youtube.com/embed/smc28GgCeNY 119 2026-09-29T15:20:46+00:00 yes https://xdme.com/watch-book5-q122.html https://xdme.com/book5-thumbs/page-122.jpg Stop, Thief! Why Is Looting a Science Problem? Looting means taking objects from a site without permission. Once an object is taken out of its place, the clues about where it was found are often lost. That makes it much harder https://socialmedia.xdme.com/tony/videos-book2/page-122.mp4 https://www.youtube.com/embed/8fy9-ocvq7o 119 2026-09-29T15:20:47+00:00 yes https://xdme.com/watch-book5-q123.html https://xdme.com/book5-thumbs/page-123.jpg Big Questions! Why Do Kids' Questions Still Matter? Every scientist started out by asking a question. Kids often ask questions that grown-ups have not thought about, and good questions can lead to new investigations. Asking why is a https://socialmedia.xdme.com/tony/videos-book2/page-123.mp4 https://www.youtube.com/embed/6yFl-Urx9fs 119 2026-09-29T22:25:16+00:00 yes https://xdme.com/watch-book5-q124.html https://xdme.com/book5-thumbs/page-124.jpg Write It Down! Why Is a Notebook a Tool? A notebook helps scientists remember what they saw, measured, and thought. Notes can be checked later and shared with others. Just like a shovel or a microscope, a notebook is a to https://socialmedia.xdme.com/tony/videos-book2/page-124.mp4 https://www.youtube.com/embed/qJhHNFk4E1w 126 2026-09-29T16:27:03+00:00 yes https://xdme.com/watch-book5-q125.html https://xdme.com/book5-thumbs/page-125.jpg Detective Mode On! How Do You Think Like a Detective? Detectives and scientists both look closely at clues. They ask questions, test ideas, and check their work. Try it yourself: pick something, observe it, and write down what you not https://socialmedia.xdme.com/tony/videos-book2/page-125.mp4 https://www.youtube.com/embed/B_lXAzTutRk 119 2026-09-29T16:36:45+00:00 yes https://xdme.com/watch-book5-q126.html https://xdme.com/book5-thumbs/page-126.jpg Happy New Year! Why Do We Count Years? A year is about how long it takes Earth to travel once around the Sun. Counting years helps people keep track of seasons and plan things, like when to plant crops or celebrate. Cal https://socialmedia.xdme.com/tony/videos-book2/page-126.mp4 https://www.youtube.com/embed/ZFujfNRQIlI 119 2026-09-29T16:34:43+00:00 yes https://xdme.com/watch-book5-q127.html https://xdme.com/book5-thumbs/page-127.jpg Sun Up, Sun Down! Why Do We Have Days and Nights? Earth spins like a top, and one full spin takes about 24 hours. When your part of Earth faces the Sun, it is day. When it turns away, it is night. https://socialmedia.xdme.com/tony/videos-book2/page-127.mp4 https://www.youtube.com/embed/aMyf0j8-AXQ 119 2026-09-29T17:04:53+00:00 yes https://xdme.com/watch-book5-q128.html https://xdme.com/book5-thumbs/page-128.jpg Hot, Cold, Repeat! Why Do Seasons Change? Earth is tilted as it travels around the Sun. That tilt means different parts of Earth get more direct sunlight at different times of the year. Those changes give us summer, fall, https://socialmedia.xdme.com/tony/videos-book2/page-128.mp4 https://www.youtube.com/embed/93KGpSuKoNk 119 2026-09-29T16:44:46+00:00 yes https://xdme.com/watch-book5-q129.html https://xdme.com/book5-thumbs/page-129.jpg Moon Shapes! Why Does the Moon Change Shape? The Moon does not make its own light. We see it because sunlight bounces off it, and as the Moon travels around Earth, we see different amounts of its bright side. That is why it s https://socialmedia.xdme.com/tony/videos-book2/page-129.mp4 https://www.youtube.com/embed/uaETecPnNCc 119 2026-09-29T16:46:17+00:00 yes https://xdme.com/watch-book5-q130.html https://xdme.com/book5-thumbs/page-130.jpg Counting Years! How Do People Keep Track of Them? Years are one of the big ways people measure time. Calendars, records, and clues like tree rings and rock layers help us count them. Whether it is your age or a very old fossil, ye https://socialmedia.xdme.com/tony/videos-book2/page-130.mp4 https://www.youtube.com/embed/7PoyFJwFFXE 119 2026-09-29T17:04:22+00:00 yes https://xdme.com/watch-book5-q131.html https://xdme.com/book5-thumbs/page-131.jpg Time Travelers? Why Are There Time Zones? Earth is round and turns, so the Sun is high in the sky in different places at different times. Time zones let people in each region have their clocks match the day and night aroun https://socialmedia.xdme.com/tony/videos-book2/page-131.mp4 https://www.youtube.com/embed/tgJs1H46YBY 118 2026-09-29T17:14:25+00:00 yes https://xdme.com/watch-book5-q132.html https://xdme.com/book5-thumbs/page-132.jpg Tree Rings! Why Do Rings Count Years? Many trees grow a new ring each year, and each ring records what that year was like. Wide rings often mean a good year for growing, and narrow rings can mean a harder one. Scientis https://socialmedia.xdme.com/tony/videos-book2/page-132.mp4 https://www.youtube.com/embed/EbrooxUy6iM 119 2026-09-29T16:55:49+00:00 yes https://xdme.com/watch-book5-q133.html https://xdme.com/book5-thumbs/page-133.jpg Swing and Sand! Why Do Some Clocks Use Swings or Sand? Some clocks count with something that repeats steadily. A pendulum swings back and forth at a steady pace, and sand in an hourglass runs at a steady pace too. People used many idea https://socialmedia.xdme.com/tony/videos-book2/page-133.mp4 https://www.youtube.com/embed/V2RnuVh2s0Q 119 2026-09-29T16:55:50+00:00 yes https://xdme.com/watch-book5-q134.html https://xdme.com/book5-thumbs/page-134.jpg Deep Time! Why Can't We Wear a Clock for It? Earth is billions of years old, and that is far too long for a watch. Scientists use clues like rock layers and fossils to think about deep time. Big spans of time need different t https://socialmedia.xdme.com/tony/videos-book2/page-134.mp4 https://www.youtube.com/embed/4H-aIaOoNL0 119 2026-09-29T17:23:27+00:00 yes https://xdme.com/watch-book5-q135.html https://xdme.com/book5-thumbs/page-135.jpg Tick Tock, Body Clock! Why Does Your Body Have Rhythms? Your body has natural cycles, like feeling sleepy at night and awake in the day. These rhythms are helped along by light and by daily habits. A regular sleep routine can help your https://socialmedia.xdme.com/tony/videos-book2/page-135.mp4 https://www.youtube.com/embed/ur96_4QVpb8 119 2026-09-29T17:35:12+00:00 yes https://xdme.com/watch-book5-q136.html https://xdme.com/book5-thumbs/page-136.jpg Ring Around the Tree! Another Look at Tree Ring Time Tree rings are a natural record of years. Each ring is one year of growth, so counting them can tell a tree's age. Rings can also show scientists clues about weather from long ago. https://socialmedia.xdme.com/tony/videos-book2/page-136.mp4 https://www.youtube.com/embed/AojOeYdgd4c 119 2026-09-29T17:13:55+00:00 yes https://xdme.com/watch-book5-q137.html https://xdme.com/book5-thumbs/page-137.jpg Before and After! Why Does That Order Matter? Knowing what happened first and what happened next helps us understand stories and history. In rock layers, older layers are usually underneath, and that order gives scientists clu https://socialmedia.xdme.com/tony/videos-book2/page-137.mp4 https://www.youtube.com/embed/eOs8wgOXI_0 125 2026-09-29T17:23:59+00:00 yes https://xdme.com/watch-book5-q138.html https://xdme.com/book5-thumbs/page-138.jpg Be Patient! Why Do Some Answers Take Time? Some questions need lots of careful digging, testing, or waiting for new tools. Science can be slow, and it can take years to learn something new. Patience is part of being a scien https://socialmedia.xdme.com/tony/videos-book2/page-138.mp4 https://www.youtube.com/embed/wM6JMhLyr9w 124 2026-09-29T17:33:11+00:00 yes https://xdme.com/watch-book5-q139.html https://xdme.com/book5-thumbs/page-139.jpg Yesterday vs. Tomorrow! Why Do They Feel Different? We remember yesterday, but tomorrow has not happened yet. Our brains use memories to look back and imagination to look ahead. That is one reason the past and future feel so differe https://socialmedia.xdme.com/tony/videos-book2/page-139.mp4 https://www.youtube.com/embed/z8KaZahROiw 125 2026-09-29T17:44:46+00:00 yes https://xdme.com/watch-book5-q140.html https://xdme.com/book5-thumbs/page-140.jpg Why Does History Use Different Clocks Than Homework? Homework is measured in minutes and hours, but history is measured in years, centuries, and much longer spans. Scientists choose a time scale that fits what they are studying. It i https://socialmedia.xdme.com/tony/videos-book2/page-140.mp4 https://www.youtube.com/embed/em49NfAV7wg 130 2026-09-29T17:44:47+00:00 yes https://xdme.com/watch-book5-q141.html https://xdme.com/book5-thumbs/page-141.jpg Same Age, Different Look! Why Can Two Fossils Differ? Two fossils can be from about the same time but come from different kinds of animals. They might also have lived in different places or eaten different things. Being the same age d https://socialmedia.xdme.com/tony/videos-book2/page-141.mp4 https://www.youtube.com/embed/-PwN5EwiebY 125 2026-09-29T18:11:27+00:00 yes https://xdme.com/watch-book5-q142.html https://xdme.com/book5-thumbs/page-142.jpg A Tiny Slice! Why Is Your Life a Small Part of Earth Time? Earth is about 4.5 billion years old, and a human life lasts only a tiny part of that. Even so, your time matters, because you can learn and help take care of the world. Every pers https://socialmedia.xdme.com/tony/videos-book2/page-142.mp4 https://www.youtube.com/embed/CZXOeO7UR7M 120 2026-09-29T18:34:09+00:00 yes https://xdme.com/watch-book5-q143.html https://xdme.com/book5-thumbs/page-143.jpg Save It for Later! Why Do We Save Finds for the Future? Future scientists will have new tools and new questions. Saving fossils and artifacts in museums lets them study things we cannot yet learn from. Caring for finds is a gift to the https://socialmedia.xdme.com/tony/videos-book2/page-143.mp4 https://www.youtube.com/embed/mC5bKJRTICw 122 2026-09-29T18:20:31+00:00 yes https://xdme.com/watch-book5-q144.html https://xdme.com/book5-thumbs/page-144.jpg You're a Timekeeper! Why Can You Be One Too? You can keep track of time and change in your own life. Try a diary, a growth chart, or photos taken each year to notice how things change. That is a little like what scientists do https://socialmedia.xdme.com/tony/videos-book2/page-144.mp4 https://www.youtube.com/embed/sU_iq3okDyE 119 2026-09-29T18:43:11+00:00 yes https://xdme.com/watch-book5-q145.html https://xdme.com/book5-thumbs/page-145.jpg Tick, Tock, Ding! Why Are There So Many Kinds of Clocks? People have measured time in many ways, from shadows and water to swinging weights and digital chips. Different clocks fit different needs, like a quick timer or a wall clock. New https://socialmedia.xdme.com/tony/videos-book2/page-145.mp4 https://www.youtube.com/embed/3zrfXCkGHY4 121 2026-09-29T18:38:40+00:00 yes https://xdme.com/watch-book5-q146.html https://xdme.com/book5-thumbs/page-146.jpg Bonus Day! Why Do Some Years Get an Extra Day? A year is a little longer than 365 days, at about 365 and a quarter days. To keep our calendar lined up, most years that divide evenly by four get an extra day, February 29th. Thos https://socialmedia.xdme.com/tony/videos-book2/page-146.mp4 https://www.youtube.com/embed/rCj-tHdDsMA 126 2026-09-29T18:50:44+00:00 yes https://xdme.com/watch-book5-q147.html https://xdme.com/book5-thumbs/page-147.jpg Layer by Layer! Why Are Older Layers Usually Lower? New layers of mud and sand usually settle on top of ones that were already there. So in many places, the bottom layers are the oldest and the top layers are the newest. Geologists https://socialmedia.xdme.com/tony/videos-book2/page-147.mp4 https://www.youtube.com/embed/wqonR8cTDMk 123 2026-09-29T18:47:42+00:00 yes https://xdme.com/watch-book5-q148.html https://xdme.com/book5-thumbs/page-148.jpg Are We There Yet? Why Does Waiting Feel So Long? When you are waiting and paying attention to the clock, time can feel slower. When you are having fun, it can feel faster. The clock ticks steadily, but how we feel about time can https://socialmedia.xdme.com/tony/videos-book2/page-148.mp4 https://www.youtube.com/embed/PhqxqHOrx_k 119 2026-09-29T19:08:18+00:00 yes https://xdme.com/watch-book5-q149.html https://xdme.com/book5-thumbs/page-149.jpg The End Is Yours! Why Does This Book End With You? Science never really ends, because there are always new questions to ask. The book ends with you because you can keep exploring, wondering, and learning. Your questions can be the https://socialmedia.xdme.com/tony/videos-book2/page-149.mp4 https://www.youtube.com/embed/7HvhiVRPm3E 119 2026-09-29T19:16:50+00:00 yes https://xdme.com/watch-book5-q150.html https://xdme.com/book5-thumbs/page-150.jpg Time Detective Mode! How Do You Think Like One? A time detective looks for clues about what happened before and how long ago. They use layers, records, and measurements, and they test their ideas. Keep asking questions, and you https://socialmedia.xdme.com/tony/videos-book2/page-150.mp4 https://www.youtube.com/embed/B2r3nMmMVZI 122 2026-09-29T19:16:20+00:00 yes https://xdme.com/watch-book6-q001.html https://xdme.com/book6-thumbs/page-001.jpg Why Is the Ocean Salty? Rain slowly wears tiny bits of salt and other minerals out of rocks. Rivers carry those bits to the sea. Then the sun lifts the water away, but the salt stays behind. https://socialmedia.xdme.com/tony/videos-book6/page-001.mp4 https://www.youtube.com/embed/6vX5Zll2r7w 133 2026-10-01T16:16:06+00:00 yes https://xdme.com/watch-book6-q002.html https://xdme.com/book6-thumbs/page-002.jpg Why Are There Waves? Wind pushes on the surface of the water. That push travels across the sea as a wave. The water mostly bobs up and down, but the wave's shape moves forward. https://socialmedia.xdme.com/tony/videos-book6/page-002.mp4 https://www.youtube.com/embed/uEn9DItoptU 124 2026-10-01T17:30:23+00:00 yes https://xdme.com/watch-book6-q003.html https://xdme.com/book6-thumbs/page-003.jpg Why Do Tides Go in and Out? The Moon tugs on Earth's oceans, and the water bulges toward it. Earth turns under those bulges. So a beach sees the bulge as high tide, and the water line rises and falls. https://socialmedia.xdme.com/tony/videos-book6/page-003.mp4 https://www.youtube.com/embed/HFRGjGc0KXc 123 2026-10-01T20:36:21+00:00 yes https://xdme.com/watch-book6-q004.html https://xdme.com/book6-thumbs/page-004.jpg Why Is the Ocean Blue? Sunlight looks white, but it is a mix of colors. Water soaks up reds and yellows first. Blue light lasts the longest and bounces back to your eyes. https://socialmedia.xdme.com/tony/videos-book6/page-004.mp4 https://www.youtube.com/embed/KHQ-ajqDhT0 119 2026-10-01T20:51:57+00:00 yes https://xdme.com/watch-book6-q005.html https://xdme.com/book6-thumbs/page-005.jpg Why Does the Shore Keep Changing? Waves, tides, storms, and rivers all move sand. A beach is a pile in motion. Today's beach is last year's sand, just passing through! https://socialmedia.xdme.com/tony/videos-book6/page-005.mp4 https://www.youtube.com/embed/W6FYozf2Ocs 125 2026-10-01T21:16:01+00:00 yes https://xdme.com/watch-book6-q006.html https://xdme.com/book6-thumbs/page-006.jpg Why Does Foam Show Up on Waves? When a wave breaks, it mixes air into the water. Tiny bubbles form, and bits from living things in the sea help them stick together. Piled up, they make foam. https://socialmedia.xdme.com/tony/videos-book6/page-006.mp4 https://www.youtube.com/embed/daMuwOEC2Ro 121 2026-10-01T21:20:32+00:00 yes https://xdme.com/watch-book6-q007.html https://xdme.com/book6-thumbs/page-007.jpg Why Can the Water Pull You Out? Waves push extra water onto the beach. That water has to go back out to sea. Sometimes it finds a narrow path and rushes out. If caught, stay calm and swim sideways, parallel to th https://socialmedia.xdme.com/tony/videos-book6/page-007.mp4 https://www.youtube.com/embed/ISiJFk_a0Ho 127 2026-10-01T21:41:59+00:00 yes https://xdme.com/watch-book6-q008.html https://xdme.com/book6-thumbs/page-008.jpg Why Do Tide Pools Appear? When the tide drops, some seawater stays trapped in rocky bowls. Those bowls become tiny leftover oceans. Animals wait there until the sea comes back. https://socialmedia.xdme.com/tony/videos-book6/page-008.mp4 https://www.youtube.com/embed/yUUydlGUygE 123 2026-10-01T21:57:32+00:00 yes https://xdme.com/watch-book6-q009.html https://xdme.com/book6-thumbs/page-009.jpg Why Is Some Sand Wet Under the Dry Top? Sand is a pile of tiny grains with tiny gaps between them. Water hides in those gaps. The sun dries the top first, but below stays damp. https://socialmedia.xdme.com/tony/videos-book6/page-009.mp4 https://www.youtube.com/embed/KncHyx_x_U8 121 2026-10-01T22:04:36+00:00 yes https://xdme.com/watch-book6-q010.html https://xdme.com/book6-thumbs/page-010.jpg Why Is Beach Sand Often Tiny? Waves tumble rocks for years and years. Big pieces smash and rub against each other. Slowly, they wear down into tiny grains of sand. https://socialmedia.xdme.com/tony/videos-book6/page-010.mp4 https://www.youtube.com/embed/Rhbu7pZpS3Y 120 2026-10-01T23:01:28+00:00 yes https://xdme.com/watch-book6-q011.html https://xdme.com/book6-thumbs/page-011.jpg Why Do Seashells Wash Up? A shell is a leftover house. After the animal dies or leaves, waves carry the empty house to shore. Light, hollow shells float and roll along. https://socialmedia.xdme.com/tony/videos-book6/page-011.mp4 https://www.youtube.com/embed/FUi0L_xD2pA 120 2026-10-01T23:24:32+00:00 yes https://xdme.com/watch-book6-q012.html https://xdme.com/book6-thumbs/page-012.jpg Why Does Seaweed Pile on the Beach? Storms and strong waves tear seaweed loose. Many seaweeds have floats, so they drift on the water. When the tide drops, they are left in a line on the sand. https://socialmedia.xdme.com/tony/videos-book6/page-012.mp4 https://www.youtube.com/embed/turKdMxiX8U 125 2026-10-01T23:43:06+00:00 yes https://xdme.com/watch-book6-q013.html https://xdme.com/book6-thumbs/page-013.jpg Why Does the Ocean Smell Like That? The sea smell is a mix. It has salt spray, rotting seaweed, and gases from tiny living things. Your nose reads all of it at once. If a beach smells like rotten eggs and looks odd, https://socialmedia.xdme.com/tony/videos-book6/page-013.mp4 https://www.youtube.com/embed/1roJnsI27UE 121 2026-10-02T00:10:12+00:00 yes https://xdme.com/watch-book6-q014.html https://xdme.com/book6-thumbs/page-014.jpg Why Do Some Beaches Have Pebbles? Not every shore has the time or the waves to grind rock all the way to powder. Strong waves can carry fine sand away and leave the heavier stones behind. Nearby cliffs keep feeding https://socialmedia.xdme.com/tony/videos-book6/page-014.mp4 https://www.youtube.com/embed/hqTBVZAn_sI 127 2026-10-02T00:50:53+00:00 yes https://xdme.com/watch-book6-q015.html https://xdme.com/book6-thumbs/page-015.jpg Why Do Waves Get Bigger Near Shore? In deep water, a wave is a long, low shape. Near shore, the bottom crowds it from below. So the wave stands taller, until it breaks. https://socialmedia.xdme.com/tony/videos-book6/page-015.mp4 https://www.youtube.com/embed/Z2D9AhJbe6E 126 2026-10-02T01:43:12+00:00 yes https://xdme.com/watch-book6-q016.html https://xdme.com/book6-thumbs/page-016.jpg Why Is There a Line of Junk on the Sand? High tide pushes floating things up the beach. When the water falls, they stay where the tide stopped. So shells, seaweed, wood, and trash end up in a stripe. https://socialmedia.xdme.com/tony/videos-book6/page-016.mp4 https://www.youtube.com/embed/qqBZD3DG8p8 119 2026-10-02T02:11:00+00:00 yes https://xdme.com/watch-book6-q017.html https://xdme.com/book6-thumbs/page-017.jpg Why Is Some Sand Black? Black sand is often tiny bits of dark volcanic rock. Or it can be heavy dark minerals left after the lighter grains wash away. The color comes from the parent rock. https://socialmedia.xdme.com/tony/videos-book6/page-017.mp4 https://www.youtube.com/embed/xSmECC0gyCQ 121 2026-10-02T02:38:55+00:00 yes https://xdme.com/watch-book6-q018.html https://xdme.com/book6-thumbs/page-018.jpg Why Does Wet Sand Hold a Castle? A little bit of water acts like glue between sand grains. Too dry, and the walls crumble. Too soupy, and they slump. Deep holes can collapse, so keep them small. https://socialmedia.xdme.com/tony/videos-book6/page-018.mp4 https://www.youtube.com/embed/EyACtsObhAY 119 2026-10-02T03:10:34+00:00 yes https://xdme.com/watch-book6-q019.html https://xdme.com/book6-thumbs/page-019.jpg Why Do Footprints Fill with Water? Under wet beach sand, there is more water. When you step, your foot squeezes the grains together. That hidden water rushes into the print. https://socialmedia.xdme.com/tony/videos-book6/page-019.mp4 https://www.youtube.com/embed/AtVpR9miQUw 117 2026-10-01T22:27:48+00:00 yes https://xdme.com/watch-book6-q020.html https://xdme.com/book6-thumbs/page-020.jpg Why Does Salt Help You Float? Salt water is denser than fresh water. That means the same cup of water is heavier. Denser water pushes up harder, so floating gets easier. https://socialmedia.xdme.com/tony/videos-book6/page-020.mp4 https://www.youtube.com/embed/lU783QkUMSE 118 2026-10-02T03:47:09+00:00 yes https://xdme.com/watch-book6-q021.html https://xdme.com/book6-thumbs/page-021.jpg Why Is the Ocean Colder than a Puddle? A puddle is thin and sits in the sun. The ocean is deep, and most of its water never gets a long turn in the heat. Wind and currents also mix cold water upward. https://socialmedia.xdme.com/tony/videos-book6/page-021.mp4 https://www.youtube.com/embed/MkC7rrHs6eQ 121 2026-10-02T05:02:57+00:00 yes https://xdme.com/watch-book6-q022.html https://xdme.com/book6-thumbs/page-022.jpg Why Do Rocks Get Holes By the Sea? Waves throw sand and pebbles at rocks. Soft spots wear away first. Some animals also drill tiny homes in the rock. Do not put fingers in mystery holes, since animals may live there https://socialmedia.xdme.com/tony/videos-book6/page-022.mp4 https://www.youtube.com/embed/VJiVEesmwow 116 2026-10-02T05:58:21+00:00 yes https://xdme.com/watch-book6-q023.html https://xdme.com/book6-thumbs/page-023.jpg Why Does Spray Feel Colder than the Air? Spray is tiny drops of cold sea water. When it lands on you, it steals heat from your skin. As some of it dries, it steals even more. https://socialmedia.xdme.com/tony/videos-book6/page-023.mp4 https://www.youtube.com/embed/mBLNMVt0tF8 112 2026-10-02T06:53:39+00:00 yes https://xdme.com/watch-book6-q024.html https://xdme.com/book6-thumbs/page-024.jpg Why Is the Horizon a Straight Line? Earth is huge and curved. From the beach, you only see a tiny slice of that curve. So the far edge of the water looks like a straight line. https://socialmedia.xdme.com/tony/videos-book6/page-024.mp4 https://www.youtube.com/embed/UZmttKS4tBQ 116 2026-10-02T07:24:58+00:00 yes https://xdme.com/watch-book6-q025.html https://xdme.com/book6-thumbs/page-025.jpg Why Do Birds Follow the Tide Line? When the water falls, it uncovers snacks like worms, tiny clams, and leftover bits. Birds walk the wet stripe like a moving buffet. Each tide sets a new table. https://socialmedia.xdme.com/tony/videos-book6/page-025.mp4 https://www.youtube.com/embed/1BmnvjB2HHM 120 2026-10-02T07:09:38+00:00 yes https://xdme.com/watch-book6-q026.html https://xdme.com/book6-thumbs/page-026.jpg Why Do Fish Have Gills? Fish pull oxygen out of the water with thin gill tissues. We air-breathers use lungs instead. It is the same job with a different tool. https://socialmedia.xdme.com/tony/videos-book6/page-026.mp4 https://www.youtube.com/embed/ujqV8zv8kH0 119 2026-10-02T07:53:06+00:00 yes https://xdme.com/watch-book6-q027.html https://xdme.com/book6-thumbs/page-027.jpg Why Don't Fish Drown? Drowning happens when lungs fill with water, and fish do not use lungs. They use gills, which are built to pull oxygen out of water. That is why a fish is safe underwater but strug https://socialmedia.xdme.com/tony/videos-book6/page-027.mp4 https://www.youtube.com/embed/1jG8Vix7CVs 120 2026-10-02T08:52:12+00:00 yes https://xdme.com/watch-book6-q028.html https://xdme.com/book6-thumbs/page-028.jpg Why Do Fish Have Scales? Scales are thin plates that cover a fish's body. They protect the fish and help it slip through the water. They also grow as the fish grows. https://socialmedia.xdme.com/tony/videos-book6/page-028.mp4 https://www.youtube.com/embed/c-rsNg86Gx4 115 2026-10-02T09:29:35+00:00 yes https://xdme.com/watch-book6-q029.html https://xdme.com/book6-thumbs/page-029.jpg Why Do Some Fish Swim in Schools? Many eyes spot danger faster. A swirling crowd makes it hard for a hunter to pick one fish. So swimming together keeps each fish safer. https://socialmedia.xdme.com/tony/videos-book6/page-029.mp4 https://www.youtube.com/embed/pYyrgDT34nY 112 2026-10-02T09:43:41+00:00 yes https://xdme.com/watch-book6-q030.html https://xdme.com/book6-thumbs/page-030.jpg Why Are Fish Slippery? Fish make a thin coat of slime called mucus. It helps them glide through water. It also blocks some germs and helps a fish slip out of a grab. https://socialmedia.xdme.com/tony/videos-book6/page-030.mp4 https://www.youtube.com/embed/WB3ccPwFHrM 110 2026-10-02T09:46:42+00:00 yes https://xdme.com/watch-book6-q031.html https://xdme.com/book6-thumbs/page-031.jpg Why Can Some Fish Glow? Some deep-sea fish make light inside their bodies with a chemical reaction. Others host glowing bacteria that live on them. The light is a tool for finding food, friends, or escape https://socialmedia.xdme.com/tony/videos-book6/page-031.mp4 https://www.youtube.com/embed/kcgEqLskWMw 119 2026-10-02T09:49:50+00:00 yes https://xdme.com/watch-book6-q032.html https://xdme.com/book6-thumbs/page-032.jpg Why Is a Flounder So Flat? Flatfish lie on the seafloor, and one side becomes the bottom. Both eyes move to the top side. A pancake shape hides well in sand. https://socialmedia.xdme.com/tony/videos-book6/page-032.mp4 https://www.youtube.com/embed/CJWMvkm5cUc 113 2026-10-02T09:52:22+00:00 yes https://xdme.com/watch-book6-q033.html https://xdme.com/book6-thumbs/page-033.jpg Why Does a Seahorse Look Like a Horse? A seahorse is a fish in disguise. Its long snout sips tiny food, and its curled tail holds on to seagrass. Bony plates replace regular scales. https://socialmedia.xdme.com/tony/videos-book6/page-033.mp4 https://www.youtube.com/embed/0oPLpwX7ErE 119 2026-10-02T09:55:26+00:00 yes https://xdme.com/watch-book6-q034.html https://xdme.com/book6-thumbs/page-034.jpg Why Does an Octopus Have Three Hearts? An octopus is a mollusk, not a fish, and it has three hearts. Two hearts serve the gills, and a third heart serves the rest of the body. That is one reason it is one of the most am https://socialmedia.xdme.com/tony/videos-book6/page-034.mp4 https://www.youtube.com/embed/1KO89hh2SIA 118 2026-10-02T09:57:57+00:00 yes https://xdme.com/watch-book6-q035.html https://xdme.com/book6-thumbs/page-035.jpg Why Can an Octopus Change Color? An octopus can match rock, sand, or coral in a blink. Tiny color cells in its skin open and close. It is like having thousands of tiny umbrellas. https://socialmedia.xdme.com/tony/videos-book6/page-035.mp4 https://www.youtube.com/embed/Bm6Jbya_ayo 117 2026-10-02T10:01:00+00:00 yes https://xdme.com/watch-book6-q036.html https://xdme.com/book6-thumbs/page-036.jpg Why Do Crabs Walk Sideways? A crab's legs fold out from the sides of its body. Its joints swing left and right more easily than front and back. So sideways is the fastest way to go. https://socialmedia.xdme.com/tony/videos-book6/page-036.mp4 https://www.youtube.com/embed/ZQoWeha-Ats 117 2026-10-02T10:03:02+00:00 yes https://xdme.com/watch-book6-q037.html https://xdme.com/book6-thumbs/page-037.jpg Why Does a Hermit Crab Wear a Shell? A hermit crab's back end is soft. It slides into an empty snail shell and carries the house along. The shell protects it, like a borrowed suit of armor. https://socialmedia.xdme.com/tony/videos-book6/page-037.mp4 https://www.youtube.com/embed/HZgNQ1_r96Y 116 2026-10-02T10:05:33+00:00 yes https://xdme.com/watch-book6-q038.html https://xdme.com/book6-thumbs/page-038.jpg Why Does a Starfish Have Five Arms? A sea star is not a fish. Most kinds have five arms around a center. Tiny tube feet line the underside. Leave live sea stars in the water. https://socialmedia.xdme.com/tony/videos-book6/page-038.mp4 https://www.youtube.com/embed/KKcaslALaUw 113 2026-10-02T10:08:05+00:00 yes https://xdme.com/watch-book6-q039.html https://xdme.com/book6-thumbs/page-039.jpg Why Can a Starfish Grow an Arm Back? A starfish is really called a sea star, because it is not a fish. If a sea star loses an arm, special cells can rebuild it. It is slow, taking weeks or months! https://socialmedia.xdme.com/tony/videos-book6/page-039.mp4 https://www.youtube.com/embed/Q5Fc8fhKZZI 116 2026-10-01T16:16:13+00:00 yes https://xdme.com/watch-book6-q040.html https://xdme.com/book6-thumbs/page-040.jpg Why Do Jellyfish Sting? A jellyfish has no claws and no teeth. Its tentacles are covered in tiny stinging cells. When something touches one, a tiny thread shoots out like a spring-loaded dart. https://socialmedia.xdme.com/tony/videos-book6/page-040.mp4 https://www.youtube.com/embed/G4LsorNN0b0 124 2026-10-01T20:36:22+00:00 yes https://xdme.com/watch-book6-q041.html https://xdme.com/book6-thumbs/page-041.jpg Why Isn't a Jellyfish a Fish? A fish has a backbone, gills, and usually scales. A jellyfish has none of those! A jelly is a soft animal called a cnidarian. Names can trick you. https://socialmedia.xdme.com/tony/videos-book6/page-041.mp4 https://www.youtube.com/embed/LCZeAKgLnqs 124 2026-10-01T20:45:25+00:00 yes https://xdme.com/watch-book6-q042.html https://xdme.com/book6-thumbs/page-042.jpg Why Do Some Clams Make Pearls? Some oysters and other mollusks can make pearls. If a bit of grit or a tiny parasite slips inside, the animal coats it with the same shiny material that lines its shell. Layer afte https://socialmedia.xdme.com/tony/videos-book6/page-042.mp4 https://www.youtube.com/embed/Aaar8TmHwu8 122 2026-10-01T20:54:58+00:00 yes https://xdme.com/watch-book6-q043.html https://xdme.com/book6-thumbs/page-043.jpg Why Do Some Fish Have Whiskers? Some fish, like catfish, have whisker-like feelers near the mouth. They are called barbels. Barbels are covered in taste and touch sensors. https://socialmedia.xdme.com/tony/videos-book6/page-043.mp4 https://www.youtube.com/embed/lZFvHUpeNhA 118 2026-10-01T21:12:30+00:00 yes https://xdme.com/watch-book6-q044.html https://xdme.com/book6-thumbs/page-044.jpg Why Do Flying Fish Jump? A flying fish shoots out of the water and spreads its long, stiff fins like wings. It does not flap like a bird. It glides above the waves! https://socialmedia.xdme.com/tony/videos-book6/page-044.mp4 https://www.youtube.com/embed/t1K6lsnLlwk 119 2026-10-01T21:23:34+00:00 yes https://xdme.com/watch-book6-q045.html https://xdme.com/book6-thumbs/page-045.jpg Why Does an Eel Look Like a Snake? An eel is a long fish. A snake is a long reptile. They have a similar shape because a long, skinny tube is perfect for slipping through rocks, cracks, and mud. https://socialmedia.xdme.com/tony/videos-book6/page-045.mp4 https://www.youtube.com/embed/GGdboeFNFZA 118 2026-10-01T22:05:08+00:00 yes https://xdme.com/watch-book6-q046.html https://xdme.com/book6-thumbs/page-046.jpg Why Does a Pufferfish Puff Up? When a pufferfish feels danger, it gulps water very fast. Its stretchy belly swells like a balloon, and its spines stick straight out. A big, spiky ball is much harder to bite than https://socialmedia.xdme.com/tony/videos-book6/page-046.mp4 https://www.youtube.com/embed/-GkQjmY5TQ4 117 2026-10-01T22:57:27+00:00 yes https://xdme.com/watch-book6-q047.html https://xdme.com/book6-thumbs/page-047.jpg Why Do Some Fish Live in the Dark? Sunlight fades as you go deeper in the ocean. In the deep sea, it is dark all day and all night. But food still drifts down or swims by, so animals that can find it without sunligh https://socialmedia.xdme.com/tony/videos-book6/page-047.mp4 https://www.youtube.com/embed/KneumBN3J4E 115 2026-10-01T23:29:03+00:00 yes https://xdme.com/watch-book6-q048.html https://xdme.com/book6-thumbs/page-048.jpg Why Doesn't an Anemone Sting a Clownfish? A sea anemone has tentacles with stinging cells that can sting most fish. But a clownfish wears a special coat of mucus, which is a kind of slime. That coat keeps the anemone from https://socialmedia.xdme.com/tony/videos-book6/page-048.mp4 https://www.youtube.com/embed/QLY0JWVxA-k 117 2026-10-02T00:02:09+00:00 yes https://xdme.com/watch-book6-q049.html https://xdme.com/book6-thumbs/page-049.jpg Why Do Shrimp Dart Backward? A shrimp can flip its tail fan under its body and shoot backward in a blink. Its tail is like a paddle, and one hard flex throws the shrimp away from danger. Walking forward is for https://socialmedia.xdme.com/tony/videos-book6/page-049.mp4 https://www.youtube.com/embed/s2MUyGjrBe0 117 2026-10-02T00:46:18+00:00 yes https://xdme.com/watch-book6-q050.html https://xdme.com/book6-thumbs/page-050.jpg Why Do Barnacles Stick So Hard? A barnacle is a crustacean, so it is a cousin of crabs. A baby barnacle swims until it finds a spot. Then it cements its head to a rock, a boat, or even a whale! https://socialmedia.xdme.com/tony/videos-book6/page-050.mp4 https://www.youtube.com/embed/cCYmwm4LsVY 119 2026-10-02T01:43:14+00:00 yes https://xdme.com/watch-book6-q051.html https://xdme.com/book6-thumbs/page-051.jpg Why Do Whales Breathe Air? A whale looks like a fish, but it is a mammal, like you. That means it has lungs, not gills, and it must come up to breathe air. It holds one big breath for many minutes, then retu https://socialmedia.xdme.com/tony/videos-book6/page-051.mp4 https://www.youtube.com/embed/NBZzGRFyf2c 118 2026-10-02T02:23:43+00:00 yes https://xdme.com/watch-book6-q052.html https://xdme.com/book6-thumbs/page-052.jpg Why Do Whales Have a Blowhole? A blowhole is a whale's nose, but it sits on top of the head. Long, long ago, whale ancestors had nostrils on their snouts. Over millions of years, they slowly moved to the top. https://socialmedia.xdme.com/tony/videos-book6/page-052.mp4 https://www.youtube.com/embed/I0fxaD-0-QU 124 2026-10-02T02:45:27+00:00 yes https://xdme.com/watch-book6-q053.html https://xdme.com/book6-thumbs/page-053.jpg Why Do Some Whales Sing? Some whales, especially male humpbacks, make long, patterned sounds called songs. Songs may help whales find a mate, or keep in touch across the sea. Water carries sound much farth https://socialmedia.xdme.com/tony/videos-book6/page-053.mp4 https://www.youtube.com/embed/3FGxVhCf-Ws 118 2026-10-02T03:16:35+00:00 yes https://xdme.com/watch-book6-q054.html https://xdme.com/book6-thumbs/page-054.jpg Why Do Whales Travel So Far? Many whales make long trips each year, called migrations. They feed in cold, food-rich water, and then swim to warm water to have their babies. So cold water is like a pantry, and https://socialmedia.xdme.com/tony/videos-book6/page-054.mp4 https://www.youtube.com/embed/zHbPr_NndBY 118 2026-10-02T03:40:09+00:00 yes https://xdme.com/watch-book6-q055.html https://xdme.com/book6-thumbs/page-055.jpg Why Is a Blue Whale So Huge? The blue whale is the largest animal that has ever lived. Ocean water holds up its body, so it does not have to carry all that weight like a land animal would. And its food comes i https://socialmedia.xdme.com/tony/videos-book6/page-055.mp4 https://www.youtube.com/embed/FW7AZkW2MK8 117 2026-10-02T04:26:40+00:00 yes https://xdme.com/watch-book6-q056.html https://xdme.com/book6-thumbs/page-056.jpg Why Do Some Whales Have Baleen Instead of Teeth? Some whales have no teeth. Instead, they have baleen, a row of tough, fringed plates hanging from the upper jaw. A whale gulps in water full of tiny food, then pushes the water bac https://socialmedia.xdme.com/tony/videos-book6/page-056.mp4 https://www.youtube.com/embed/WVv6yYNtMqI 111 2026-10-02T05:07:33+00:00 yes https://xdme.com/watch-book6-q057.html https://xdme.com/book6-thumbs/page-057.jpg Why Do Dolphins Click? Dolphins make rapid clicks, then listen for the echoes that come back. The echoes help them paint a picture of fish, nets, and the seafloor, even in murky water. This amazing skill https://socialmedia.xdme.com/tony/videos-book6/page-057.mp4 https://www.youtube.com/embed/Pgm-uHwMp4A 117 2026-10-02T05:58:21+00:00 yes https://xdme.com/watch-book6-q058.html https://xdme.com/book6-thumbs/page-058.jpg Why Do Dolphins Ride a Boat's Wave? A moving boat pushes up a bulge of water at the front, called the bow wave. A dolphin can surf that moving slope, and keep up with almost no extra work. It is just like a surfer ri https://socialmedia.xdme.com/tony/videos-book6/page-058.mp4 https://www.youtube.com/embed/6FDH_MAGBTQ 116 2026-10-02T06:12:24+00:00 yes https://xdme.com/watch-book6-q059.html https://xdme.com/book6-thumbs/page-059.jpg Why Do Sharks Have So Many Teeth? A shark's teeth grow in rows. When a front tooth falls out, a new one from the row behind moves up to take its place. Hunting is rough on teeth, so a shark always has a refill row https://socialmedia.xdme.com/tony/videos-book6/page-059.mp4 https://www.youtube.com/embed/8wqQ_Ibfe3w 117 2026-10-02T06:33:03+00:00 yes https://xdme.com/watch-book6-q060.html https://xdme.com/book6-thumbs/page-060.jpg Why Do Many Sharks Keep Swimming? Sharks breathe with gills, and gills need fresh water flowing over them. Many open-water sharks swim with their mouths slightly open, so water streams in all the time. For those sh https://socialmedia.xdme.com/tony/videos-book6/page-060.mp4 https://www.youtube.com/embed/2OK0mcA0mT4 111 2026-10-02T06:53:40+00:00 yes https://xdme.com/watch-book6-q061.html https://xdme.com/book6-thumbs/page-061.jpg Why Do Some Sharks Look Like Carpets? Carpet sharks, such as wobbegongs, have blotchy, patterned skin and little tassels around the mouth. That makes them look just like the reef floor. Prey swims close, and the shark https://socialmedia.xdme.com/tony/videos-book6/page-061.mp4 https://www.youtube.com/embed/ZwfdvfPU58c 111 2026-10-02T07:04:36+00:00 yes https://xdme.com/watch-book6-q062.html https://xdme.com/book6-thumbs/page-062.jpg Why Is a Great White Pale Underneath? A great white is dark gray on top and white underneath. That is a trick called countershading. From above, its dark back blends with the deep, dark water. https://socialmedia.xdme.com/tony/videos-book6/page-062.mp4 https://www.youtube.com/embed/au8cXVElptU 112 2026-10-02T07:47:51+00:00 yes https://xdme.com/watch-book6-q063.html https://xdme.com/book6-thumbs/page-063.jpg Why Don't Most Sharks Hunt People? Sharks hunt fish, seals, and other ocean animals. A person has a strange, bony shape and is not what sharks normally eat. Most sharks never bite a person at all, and when a shark d https://socialmedia.xdme.com/tony/videos-book6/page-063.mp4 https://www.youtube.com/embed/vnJC9C586jg 117 2026-10-02T09:02:27+00:00 yes https://xdme.com/watch-book6-q064.html https://xdme.com/book6-thumbs/page-064.jpg Why Does a Hammerhead Have a Hammer? A hammerhead's head is a long, flat bar, with an eye at each tip. Under the head are special sensors that can feel faint electricity from other animals. That shape is a tool, not a https://socialmedia.xdme.com/tony/videos-book6/page-064.mp4 https://www.youtube.com/embed/7l2eXMGk1Pg 112 2026-10-02T09:32:05+00:00 yes https://xdme.com/watch-book6-q065.html https://xdme.com/book6-thumbs/page-065.jpg Why Can a Shark Smell a Tiny Bit of Blood? A shark's nose is a pair of pits on its snout. Water flows in, and tiny sensors inside pick up smells. Those sensors are so sharp that a faint trail can point toward an injured fis https://socialmedia.xdme.com/tony/videos-book6/page-065.mp4 https://www.youtube.com/embed/BH7FFY99hh4 117 2026-10-02T09:40:09+00:00 yes https://xdme.com/watch-book6-q066.html https://xdme.com/book6-thumbs/page-066.jpg Why Is a Ray So Flat? Rays are related to sharks, and their bodies are flattened. Their wide fins work like wings, and many rays lie on the sand or glide just above it. A flat body is great for hiding o https://socialmedia.xdme.com/tony/videos-book6/page-066.mp4 https://www.youtube.com/embed/_fZyk6ZRYnw 115 2026-10-02T09:42:40+00:00 yes https://xdme.com/watch-book6-q067.html https://xdme.com/book6-thumbs/page-067.jpg Why Does a Manta Look Like It Is Flying? A manta ray flaps its huge, pointed fins up and down, and it looks like a bird in flight. But a manta is swimming, not flying. Water is much thicker than air. https://socialmedia.xdme.com/tony/videos-book6/page-067.mp4 https://www.youtube.com/embed/jBDeTeDlq0g 120 2026-10-02T09:46:44+00:00 yes https://xdme.com/watch-book6-q068.html https://xdme.com/book6-thumbs/page-068.jpg Why Is a Whale Shark Not a Whale? A whale shark is the biggest fish in the sea. It is a shark, not a whale. A whale is a mammal with lungs, while a fish has gills. The whale shark is the biggest fish alive. https://socialmedia.xdme.com/tony/videos-book6/page-068.mp4 https://www.youtube.com/embed/svA8r3gUExk 108 2026-10-02T09:49:17+00:00 yes https://xdme.com/watch-book6-q069.html https://xdme.com/book6-thumbs/page-069.jpg Why Do Orcas Hunt Together? Orcas are the largest members of the dolphin family, and they live in family groups called pods. Working together, a pod can catch meals that one orca could not. Different pods eve https://socialmedia.xdme.com/tony/videos-book6/page-069.mp4 https://www.youtube.com/embed/W7MyPZwMYdQ 115 2026-10-02T09:52:23+00:00 yes https://xdme.com/watch-book6-q070.html https://xdme.com/book6-thumbs/page-070.jpg Why Do Seals Climb Onto Rocks? Seals hunt in the water, but they are mammals, so they need to rest on land. They climb onto rocks or sand to rest, warm up, dry off, and have pups. This is called hauling out. https://socialmedia.xdme.com/tony/videos-book6/page-070.mp4 https://www.youtube.com/embed/wmqyqd_J4oY 110 2026-10-02T09:54:55+00:00 yes https://xdme.com/watch-book6-q071.html https://xdme.com/book6-thumbs/page-071.jpg Why Do Sea Turtles Come Back to a Beach? Sea turtles often return to nest on the same stretch of coast where they hatched, even decades later. A mix of smell, Earth's magnetic field, and wave clues helps guide them home. https://socialmedia.xdme.com/tony/videos-book6/page-071.mp4 https://www.youtube.com/embed/XNhRXRdX-08 117 2026-10-02T09:57:58+00:00 yes https://xdme.com/watch-book6-q072.html https://xdme.com/book6-thumbs/page-072.jpg Why Is a Giant Squid So Hard to See? Giant squid live far down in the ocean, where sunlight fades away. People almost never meet one alive. Most clues come from beaks found in sperm whale stomachs, and rare film. https://socialmedia.xdme.com/tony/videos-book6/page-072.mp4 https://www.youtube.com/embed/W2VFA6gcRiU 112 2026-10-02T10:01:01+00:00 yes https://xdme.com/watch-book6-q073.html https://xdme.com/book6-thumbs/page-073.jpg Why Do Whales Have Blubber? Blubber is a thick layer of fat under a whale's skin. It does three jobs: it keeps heat in, it stores energy, and it helps the whale float. It is a coat, a snack pack, and a life j https://socialmedia.xdme.com/tony/videos-book6/page-073.mp4 https://www.youtube.com/embed/fA4pi3qYGiM 116 2026-10-02T10:03:03+00:00 yes https://xdme.com/watch-book6-q074.html https://xdme.com/book6-thumbs/page-074.jpg Why Do Whales Leap Out of the Water? When a whale launches most of its body out of the water, that is called a breach. Scientists think a breach can send a message, knock off hitchhikers, or give the whale a look arou https://socialmedia.xdme.com/tony/videos-book6/page-074.mp4 https://www.youtube.com/embed/N6nz0C2ocF8 115 2026-10-02T10:05:34+00:00 yes https://xdme.com/watch-book6-q075.html https://xdme.com/book6-thumbs/page-075.jpg Why Is a Manatee Called a Sea Cow? A manatee is a gentle, slow mammal that grazes on seagrass and other water plants. People nicknamed it the sea cow, because its slow grazing looks like a cow in a field. But surpri https://socialmedia.xdme.com/tony/videos-book6/page-075.mp4 https://www.youtube.com/embed/ZOj2Fs04vrk 118 2026-10-02T10:08:06+00:00 yes https://xdme.com/watch-book6-q076.html https://xdme.com/book6-thumbs/page-076.jpg Why Is Coral an Animal, Not a Rock? Coral looks like rock, but each tiny piece is an animal called a polyp, with a mouth and tentacles. The hard part is a limestone skeleton that the polyp builds around itself. Many https://socialmedia.xdme.com/tony/videos-book6/page-076.mp4 https://www.youtube.com/embed/x2VRAid2eXE 122 2026-10-01T18:00:50+00:00 yes https://xdme.com/watch-book6-q077.html https://xdme.com/book6-thumbs/page-077.jpg Why Do Corals Need Sunlight? Many reef corals have tiny plant-like partners living inside them. They are called algae. The algae catch sunlight and use it to make sugar food. https://socialmedia.xdme.com/tony/videos-book6/page-077.mp4 https://www.youtube.com/embed/RYtKM3M2pZQ 126 2026-10-01T16:16:14+00:00 yes https://xdme.com/watch-book6-q078.html https://xdme.com/book6-thumbs/page-078.jpg Why Do Reefs Look Like Cities? A coral reef is like a bustling underwater city. Branches, caves, and ledges make apartments, shops, and hideouts for thousands of animals. Fish, crabs, and worms all find a home i https://socialmedia.xdme.com/tony/videos-book6/page-078.mp4 https://www.youtube.com/embed/ObvLhHppu-Y 119 2026-10-01T16:52:38+00:00 yes https://xdme.com/watch-book6-q079.html https://xdme.com/book6-thumbs/page-079.jpg Why Do Corals Bleach? When the water stays too warm for too long, corals get stressed. They push out the tiny algae that live inside them. Without the algae, the coral turns pale and its white skeleton https://socialmedia.xdme.com/tony/videos-book6/page-079.mp4 https://www.youtube.com/embed/-uHLaAb1QQA 123 2026-10-01T17:53:22+00:00 yes https://xdme.com/watch-book6-q080.html https://xdme.com/book6-thumbs/page-080.jpg Why Can't You Stand on Coral? Coral looks like a rock, but it is alive! It is a thin layer of living animals called polyps growing on a skeleton they built. One step can crush years of slow growth in a single s https://socialmedia.xdme.com/tony/videos-book6/page-080.mp4 https://www.youtube.com/embed/-AgAqH2cWzE 118 2026-10-01T21:25:05+00:00 yes https://xdme.com/watch-book6-q081.html https://xdme.com/book6-thumbs/page-081.jpg Why Is a Kelp Forest So Tall? Giant kelp is a seaweed that races toward the light! It is a kind of algae, not a tree with wood. Even so, it can grow from the seafloor all the way up to the surface, as tall as a https://socialmedia.xdme.com/tony/videos-book6/page-081.mp4 https://www.youtube.com/embed/1zvD2Wi9s_E 119 2026-10-01T21:58:33+00:00 yes https://xdme.com/watch-book6-q082.html https://xdme.com/book6-thumbs/page-082.jpg Why Does Kelp Have Floats? Kelp grows little gas-filled floats right next to its leaves, which are called blades. The floats work like life jackets, lifting the blades up toward the sunlight. Sunlight is bri https://socialmedia.xdme.com/tony/videos-book6/page-082.mp4 https://www.youtube.com/embed/fP36wOOcE3w 120 2026-10-01T22:04:37+00:00 yes https://xdme.com/watch-book6-q083.html https://xdme.com/book6-thumbs/page-083.jpg Why Do Otters Help Kelp? Sea urchins love to munch on kelp. Sea otters love to munch on sea urchins! When otters keep the urchins in check, more kelp can stand tall. https://socialmedia.xdme.com/tony/videos-book6/page-083.mp4 https://www.youtube.com/embed/abbmzysNQ4g 119 2026-10-01T22:19:10+00:00 yes https://xdme.com/watch-book6-q084.html https://xdme.com/book6-thumbs/page-084.jpg Why Is Plankton So Important? Plankton are tiny living things that drift in the water. Plant-like plankton make food from sunlight, and animal-like plankton eat them. Fish, whales, and even corals depend on tha https://socialmedia.xdme.com/tony/videos-book6/page-084.mp4 https://www.youtube.com/embed/ZHfNUpJfHrM 118 2026-10-01T22:51:25+00:00 yes https://xdme.com/watch-book6-q085.html https://xdme.com/book6-thumbs/page-085.jpg Why Does the Sea Sometimes Glow at Night? Some tiny plankton and other sea creatures can make their own light! It happens through chemistry inside their bodies, and it is called bioluminescence. When the water is stirred, https://socialmedia.xdme.com/tony/videos-book6/page-085.mp4 https://www.youtube.com/embed/BGNT7rPlj48 119 2026-10-01T23:04:59+00:00 yes https://xdme.com/watch-book6-q086.html https://xdme.com/book6-thumbs/page-086.jpg Why Do Some Algae Make the Water Green? Some tiny plant-like drifters, called algae, can fill the water with green. When there are lots of nutrients and strong sunlight, they multiply fast. This is called a bloom. https://socialmedia.xdme.com/tony/videos-book6/page-086.mp4 https://www.youtube.com/embed/lmi0gxct_T0 122 2026-10-01T23:17:31+00:00 yes https://xdme.com/watch-book6-q087.html https://xdme.com/book6-thumbs/page-087.jpg Why Do Sponges Have Holes? A sea sponge is a living animal, not a kitchen sponge! It has no mouth. Instead, tiny holes called pores pull water in, and a bigger hole sends it out. https://socialmedia.xdme.com/tony/videos-book6/page-087.mp4 https://www.youtube.com/embed/ISPi4NOQweI 119 2026-10-01T23:34:34+00:00 yes https://xdme.com/watch-book6-q088.html https://xdme.com/book6-thumbs/page-088.jpg Why Do Anemones Look Like Flowers? An anemone looks like a flower, but it is really an animal! It is a close cousin of coral and jellyfish. Its petals are actually stinging tentacles that catch food and pull it to t https://socialmedia.xdme.com/tony/videos-book6/page-088.mp4 https://www.youtube.com/embed/Doo3ev6WsSs 118 2026-10-01T23:49:07+00:00 yes https://xdme.com/watch-book6-q089.html https://xdme.com/book6-thumbs/page-089.jpg Why Do Parrotfish Poop Sand? Parrotfish scrape algae off rocks and coral with a strong beak. They swallow bits of limestone along with it, and grinding teeth in their throats crush it into powder. The leftover https://socialmedia.xdme.com/tony/videos-book6/page-089.mp4 https://www.youtube.com/embed/gSmVDSuO_pA 118 2026-10-02T00:05:10+00:00 yes https://xdme.com/watch-book6-q090.html https://xdme.com/book6-thumbs/page-090.jpg Why Do Cleaner Fish Pick at Bigger Fish? Cleaner fish and cleaner shrimp eat pests and dead skin off bigger fish. The big fish gets cleaned, and the cleaner gets a meal. It is like a spa day on the reef, and both sides wi https://socialmedia.xdme.com/tony/videos-book6/page-090.mp4 https://www.youtube.com/embed/iBbZ8U27i5s 118 2026-10-02T00:21:13+00:00 yes https://xdme.com/watch-book6-q091.html https://xdme.com/book6-thumbs/page-091.jpg Why Do Mangroves Grow in Salt Water? Mangroves are special trees that grow in salty mud along tropical shores. Some of their roots poke up like snorkels to get air. Some can also get rid of extra salt, so they can liv https://socialmedia.xdme.com/tony/videos-book6/page-091.mp4 https://www.youtube.com/embed/XfhhXLt4-sw 120 2026-10-02T00:49:19+00:00 yes https://xdme.com/watch-book6-q092.html https://xdme.com/book6-thumbs/page-092.jpg Why Are Seagrass Beds Called Nurseries? Seagrass is a real flowering plant that grows in shallow sea water. Its blades make a leafy maze where young fish, crabs, and turtles find food and cover. That is why scientists ca https://socialmedia.xdme.com/tony/videos-book6/page-092.mp4 https://www.youtube.com/embed/Yzh_BnxDpg4 119 2026-10-02T01:25:35+00:00 yes https://xdme.com/watch-book6-q093.html https://xdme.com/book6-thumbs/page-093.jpg Why Do Some Reefs Grow in Rings? A ring reef is called an atoll. It starts as coral growing around a volcanic island. Over a very long time the island sinks, but the coral keeps growing up, leaving a ring behind. https://socialmedia.xdme.com/tony/videos-book6/page-093.mp4 https://www.youtube.com/embed/YchUoHa_gso 121 2026-10-02T03:50:46+00:00 yes https://xdme.com/watch-book6-q094.html https://xdme.com/book6-thumbs/page-094.jpg Why Is a Lagoon Calmer than the Open Sea? A lagoon sits behind a reef or an island. The reef works like a breakwater, a wall that takes the punch of big ocean waves. So outside the reef the waves smash, and inside the lago https://socialmedia.xdme.com/tony/videos-book6/page-094.mp4 https://www.youtube.com/embed/_rC8yY9RnjU 116 2026-10-02T02:49:58+00:00 yes https://xdme.com/watch-book6-q095.html https://xdme.com/book6-thumbs/page-095.jpg Why Do Some Snails Have Bright Colors on a Reef? Reef snails like cone snails and cowries can have bold, bright patterns. Sometimes the colors help the snail hide, which is called camouflage. Other times the colors are a keep-awa https://socialmedia.xdme.com/tony/videos-book6/page-095.mp4 https://www.youtube.com/embed/XlPh5n6rNg0 122 2026-10-02T03:16:36+00:00 yes https://xdme.com/watch-book6-q096.html https://xdme.com/book6-thumbs/page-096.jpg Why Do Christmas-Tree Worms Vanish? Those little colorful trees on a Christmas-tree worm are really its gills and feeding fans. The worm lives safely in a tube in the coral. If a shadow or ripple says danger, it zips https://socialmedia.xdme.com/tony/videos-book6/page-096.mp4 https://www.youtube.com/embed/zwD8Ph1jie4 110 2026-10-02T03:28:08+00:00 yes https://xdme.com/watch-book6-q097.html https://xdme.com/book6-thumbs/page-097.jpg Why Do Some Corals Come Out at Night? Many corals tuck in during the day and reach out at night. Night water can be rich in drifting plankton. Their tentacles work like tiny fishing nets! https://socialmedia.xdme.com/tony/videos-book6/page-097.mp4 https://www.youtube.com/embed/SUPUBW9YDLo 115 2026-10-02T03:43:10+00:00 yes https://xdme.com/watch-book6-q098.html https://xdme.com/book6-thumbs/page-098.jpg Why Is the Water Around a Reef So Clear? Reef corals need sunlight for their algae partners. Sunlight can only reach them if the water has few floating specks. So clear water is like a sunny kitchen, and muddy water can s https://socialmedia.xdme.com/tony/videos-book6/page-098.mp4 https://www.youtube.com/embed/pAv8eVm8NkM 118 2026-10-02T04:25:08+00:00 yes https://xdme.com/watch-book6-q099.html https://xdme.com/book6-thumbs/page-099.jpg Why Do Scientists Plant Coral? Scientists grow tiny pieces of coral in nurseries. Then trained teams attach them to damaged reefs, where they can grow into new colonies. It gives a broken reef neighborhood a hea https://socialmedia.xdme.com/tony/videos-book6/page-099.mp4 https://www.youtube.com/embed/SHIYMkIaW68 125 2026-10-02T04:37:11+00:00 yes https://xdme.com/watch-book6-q100.html https://xdme.com/book6-thumbs/page-100.jpg Why Does a Tiny Change in Heat Hurt a Whole Reef? Reef corals live in warm water, but near their heat limit. A little extra warmth for too long can cause bleaching. Because the whole reef community depends on coral, one small chan https://socialmedia.xdme.com/tony/videos-book6/page-100.mp4 https://www.youtube.com/embed/KII46grVOtI 126 2026-10-02T04:44:43+00:00 yes https://xdme.com/watch-book6-q101.html https://xdme.com/book6-thumbs/page-101.jpg Why Do Ships Float? A ship is a steel bowl full of air! The water pushes up on the ship, and that push is called buoyancy. If the push equals the ship's weight, the ship floats. https://socialmedia.xdme.com/tony/videos-book6/page-101.mp4 https://www.youtube.com/embed/UDU0TY2L5zg 118 2026-10-02T05:07:02+00:00 yes https://xdme.com/watch-book6-q102.html https://xdme.com/book6-thumbs/page-102.jpg Why Is a Keel on the Bottom of a Boat? A keel is a fin or a heavy spine under a boat. It keeps a sailboat from sliding sideways in the wind. It also helps the boat stay upright. https://socialmedia.xdme.com/tony/videos-book6/page-102.mp4 https://www.youtube.com/embed/Vsc-uI5Zah0 118 2026-10-02T05:27:47+00:00 yes https://xdme.com/watch-book6-q103.html https://xdme.com/book6-thumbs/page-103.jpg Why Do Big Ships Have Such Small-Looking Propellers? A big ship's propeller looks small next to its huge hull. But up close, its blades can be taller than a person! It pushes water backward, and the ship moves forward. https://socialmedia.xdme.com/tony/videos-book6/page-103.mp4 https://www.youtube.com/embed/K2zifGI9kd4 118 2026-10-02T05:30:17+00:00 yes https://xdme.com/watch-book6-q104.html https://xdme.com/book6-thumbs/page-104.jpg Why Does a Lighthouse Flash? A lighthouse is a tall lamp with a fingerprint. Each one flashes its own pattern, like long, short, pause. That pattern tells sailors, this cape, not that one! https://socialmedia.xdme.com/tony/videos-book6/page-104.mp4 https://www.youtube.com/embed/NdX7WXihGOk 116 2026-10-02T05:50:50+00:00 yes https://xdme.com/watch-book6-q105.html https://xdme.com/book6-thumbs/page-105.jpg Why Did Sailors Use Stars to Find Their Way? Before GPS, sailors found their way by measuring the angle of a star above the horizon. Add the exact time, and that helps tell where you are. The night sky is like a giant clock a https://socialmedia.xdme.com/tony/videos-book6/page-105.mp4 https://www.youtube.com/embed/N1mOwbgyq4E 120 2026-10-02T06:01:22+00:00 yes https://xdme.com/watch-book6-q106.html https://xdme.com/book6-thumbs/page-106.jpg Why Is a Compass Needle Twitchy on a Ship? A magnetic compass needle points toward Earth's magnetic north. But a steel ship has its own magnetic pulls, from the steel hull, engines, and electric wires. So the needle gets tu https://socialmedia.xdme.com/tony/videos-book6/page-106.mp4 https://www.youtube.com/embed/KOwi36yzUE0 125 2026-10-02T06:18:01+00:00 yes https://xdme.com/watch-book6-q107.html https://xdme.com/book6-thumbs/page-107.jpg Why Are There Lines on a Nautical Chart? A nautical chart is a map for the water. Its lines and numbers show depths, shallow spots, rocks, wrecks, and safe channels. That lets a ship's captain see the seafloor before the https://socialmedia.xdme.com/tony/videos-book6/page-107.mp4 https://www.youtube.com/embed/zC1T6k56yHg 121 2026-10-02T06:23:02+00:00 yes https://xdme.com/watch-book6-q108.html https://xdme.com/book6-thumbs/page-108.jpg Why Do We Use Latitude and Longitude? Latitude and longitude are two numbers that name any spot on Earth. Latitude tells how far north or south of the equator you are. Longitude tells how far east or west of a line thr https://socialmedia.xdme.com/tony/videos-book6/page-108.mp4 https://www.youtube.com/embed/Aa2KUea75i8 120 2026-10-02T06:41:34+00:00 yes https://xdme.com/watch-book6-q109.html https://xdme.com/book6-thumbs/page-109.jpg Why Is the International Date Line in the Pacific? Earth needs a line where the calendar date jumps. That is the International Date Line, and most of it runs through the middle of the Pacific Ocean. Putting it in the emptiest ocean https://socialmedia.xdme.com/tony/videos-book6/page-109.mp4 https://www.youtube.com/embed/KQ3Hnd0sI74 121 2026-10-02T06:43:05+00:00 yes https://xdme.com/watch-book6-q110.html https://xdme.com/book6-thumbs/page-110.jpg Why Does a Submarine Go Up and Down? A submarine has special tanks called ballast tanks. Filling them with seawater makes the sub heavier than the water it pushes aside, so it sinks. Blowing the water out with air mak https://socialmedia.xdme.com/tony/videos-book6/page-110.mp4 https://www.youtube.com/embed/oblXHNEmu_g 121 2026-10-02T07:29:01+00:00 yes https://xdme.com/watch-book6-q111.html https://xdme.com/book6-thumbs/page-111.jpg Why Do Submarines Make So Little Wake on the Surface? A wake is the trail of waves left by a hull cutting the surface. A submarine that runs deep stays below that surface. So the water above it stays almost smooth! https://socialmedia.xdme.com/tony/videos-book6/page-111.mp4 https://www.youtube.com/embed/WW74rW8Lv3M 118 2026-10-02T07:36:41+00:00 yes https://xdme.com/watch-book6-q112.html https://xdme.com/book6-thumbs/page-112.jpg Why Do Scientists Use Sonar? Sonar sends out a ping of sound, and then listens for the echo. The time the echo takes to come back tells how far away something is. Many pings can build a map of the seafloor, or https://socialmedia.xdme.com/tony/videos-book6/page-112.mp4 https://www.youtube.com/embed/jojHRR0cFTs 119 2026-10-02T08:29:43+00:00 yes https://xdme.com/watch-book6-q113.html https://xdme.com/book6-thumbs/page-113.jpg Why Is the Seafloor Mapped in Strips? The ocean is huge, so one ship can only see a skinny strip at a time. A mapping ship uses sonar that sees a wide band, called a swath, under the hull. Many strips side by side make https://socialmedia.xdme.com/tony/videos-book6/page-113.mp4 https://www.youtube.com/embed/LLququafu0k 126 2026-10-02T09:23:13+00:00 yes https://xdme.com/watch-book6-q114.html https://xdme.com/book6-thumbs/page-114.jpg Why Do Research Ships Drag Nets and Bottles? You can't understand the sea just by looking from the deck of a ship. So scientists bring a little bit of the ocean aboard! Bottles collect water, nets catch tiny plankton, and cor https://socialmedia.xdme.com/tony/videos-book6/page-114.mp4 https://www.youtube.com/embed/tEDVFUFIN70 119 2026-10-01T16:16:15+00:00 yes https://xdme.com/watch-book6-q115.html https://xdme.com/book6-thumbs/page-115.jpg Why Is a Weather Buoy Left Alone in the Ocean? A weather buoy is a floating robot weather station. It sits in the ocean for months, measuring wind, waves, temperature, and air pressure. Then it radios the numbers to satellites. https://socialmedia.xdme.com/tony/videos-book6/page-115.mp4 https://www.youtube.com/embed/a6UVQNqqfO0 117 2026-10-01T17:17:25+00:00 yes https://xdme.com/watch-book6-q116.html https://xdme.com/book6-thumbs/page-116.jpg Why Do Satellites Watch the Sea From Space? From space, one picture can show a storm, a bloom of tiny plants, and a current all at once! Satellites measure sea color, sea height, temperature, and ice. They turn those signals https://socialmedia.xdme.com/tony/videos-book6/page-116.mp4 https://www.youtube.com/embed/TaLnv-rdRbA 124 2026-10-01T20:47:55+00:00 yes https://xdme.com/watch-book6-q117.html https://xdme.com/book6-thumbs/page-117.jpg Why Is There a Dead Zone in Some Coastal Water? A dead zone is a patch of water with too little oxygen for most animals to live in. Extra nutrients from farms and cities can cause a feast of algae. But when the algae die and rot https://socialmedia.xdme.com/tony/videos-book6/page-117.mp4 https://www.youtube.com/embed/QWU3ycm3o2c 120 2026-10-01T21:08:59+00:00 yes https://xdme.com/watch-book6-q118.html https://xdme.com/book6-thumbs/page-118.jpg Why Do Currents Move Like Rivers in the Sea? An ocean current is like a river with no banks. It's a huge stream of water that flows through the sea. Wind pushes the surface, Earth's spin bends the path, and warm and cold wate https://socialmedia.xdme.com/tony/videos-book6/page-118.mp4 https://www.youtube.com/embed/lbSZJ6ykJuM 125 2026-10-02T09:36:07+00:00 yes https://xdme.com/watch-book6-q119.html https://xdme.com/book6-thumbs/page-119.jpg Why Is the Gulf Stream Famous? The Gulf Stream is a strong, warm ocean current. It leaves the Gulf of Mexico, runs up the east coast of the United States, and then heads across the Atlantic toward Europe. It's l https://socialmedia.xdme.com/tony/videos-book6/page-119.mp4 https://www.youtube.com/embed/ZLS9DmLIzpE 122 2026-10-02T09:39:38+00:00 yes https://xdme.com/watch-book6-q120.html https://xdme.com/book6-thumbs/page-120.jpg Why Do Containers Stack So High on a Ship? Shipping containers are strong steel boxes with special corners. Those corners lock together, so boxes can be stacked into a tall, tidy warehouse right on the deck. More boxes on o https://socialmedia.xdme.com/tony/videos-book6/page-120.mp4 https://www.youtube.com/embed/brHVxkGuAxI 127 2026-10-02T07:38:42+00:00 yes https://xdme.com/watch-book6-q121.html https://xdme.com/book6-thumbs/page-121.jpg Why Do Harbors Need Pilots? A harbor pilot is a local expert who steps aboard a big ship to guide it through a busy port. The captain knows the ship. The pilot knows every sandbar and current in that one harb https://socialmedia.xdme.com/tony/videos-book6/page-121.mp4 https://www.youtube.com/embed/Wi78N1HS6Lg 124 2026-10-02T09:43:11+00:00 yes https://xdme.com/watch-book6-q122.html https://xdme.com/book6-thumbs/page-122.jpg Why Do Some Boats Have Two Hulls? A catamaran has two slim hulls joined by a deck. That wide stance makes the boat harder to tip over. And two slim hulls can slice through water with less drag. https://socialmedia.xdme.com/tony/videos-book6/page-122.mp4 https://www.youtube.com/embed/fi0jqT6zjiQ 123 2026-10-02T09:46:45+00:00 yes https://xdme.com/watch-book6-q123.html https://xdme.com/book6-thumbs/page-123.jpg Why Does a Life Jacket Work? A life jacket is filled with foam or air that is much lighter than water. That gives you extra buoyancy, an upward push, so your mouth and nose can stay above the water even if you https://socialmedia.xdme.com/tony/videos-book6/page-123.mp4 https://www.youtube.com/embed/lhvpcQ2EGww 121 2026-10-02T09:52:24+00:00 yes https://xdme.com/watch-book6-q124.html https://xdme.com/book6-thumbs/page-124.jpg Why Do Divers Need Tanks? People can't breathe underwater, because our lungs can't pull oxygen out of water the way gills do. So divers carry tanks that hold compressed air, which is air squeezed into a sma https://socialmedia.xdme.com/tony/videos-book6/page-124.mp4 https://www.youtube.com/embed/ePIGkCpD0Vk 122 2026-10-02T09:57:59+00:00 yes https://xdme.com/watch-book6-q125.html https://xdme.com/book6-thumbs/page-125.jpg Why Is the Deep Ocean So Hard to Visit? The deep ocean is dark, cold, and under enormous pressure. Down there, the water above is so heavy that it could crush an ordinary submarine. It's like a stack of elephants pressin https://socialmedia.xdme.com/tony/videos-book6/page-125.mp4 https://www.youtube.com/embed/Bfv1WouKCcM 120 2026-10-01T23:34:35+00:00 yes https://xdme.com/watch-book6-q126.html https://xdme.com/book6-thumbs/page-126.jpg Why Do Hurricanes Grow Over Warm Ocean Water? A hurricane is like a giant heat engine, and warm ocean water is its fuel. Warm seawater evaporates and rises as moist air. That builds tall storm clouds, and Earth's spin twists t https://socialmedia.xdme.com/tony/videos-book6/page-126.mp4 https://www.youtube.com/embed/nCK1n5ylDbI 126 2026-10-01T23:58:38+00:00 yes https://xdme.com/watch-book6-q127.html https://xdme.com/book6-thumbs/page-127.jpg Why Does a Storm Surge Flood a Coast? A storm surge is seawater pushed onto land by a storm's strong winds and low air pressure. It isn't just rain! The wind shoves a hill of ocean toward the coast. https://socialmedia.xdme.com/tony/videos-book6/page-127.mp4 https://www.youtube.com/embed/RqClIXuqzhA 122 2026-10-02T00:23:25+00:00 yes https://xdme.com/watch-book6-q128.html https://xdme.com/book6-thumbs/page-128.jpg Why Do Sea Walls Sometimes Make Beaches Worse? A sea wall is a hard barrier that protects buildings from waves. But a wall bounces wave energy back instead of absorbing it. That churns up the sand and carries it away. https://socialmedia.xdme.com/tony/videos-book6/page-128.mp4 https://www.youtube.com/embed/QTngp9cD-38 124 2026-10-02T00:59:55+00:00 yes https://xdme.com/watch-book6-q129.html https://xdme.com/book6-thumbs/page-129.jpg Why Do Wetlands Protect Towns From Storms? Wetlands, like salt marshes and mangroves, act like a sponge and a speed bump for storm water. They are places where land and sea mix. Their plants slow the flow, and their shallow https://socialmedia.xdme.com/tony/videos-book6/page-129.mp4 https://www.youtube.com/embed/pId5899ZNLE 122 2026-10-02T01:43:14+00:00 yes https://xdme.com/watch-book6-q130.html https://xdme.com/book6-thumbs/page-130.jpg Why Is Plastic in the Ocean a Problem? Plastic is built not to rot, so it lasts a very long time in the sea. Waves and sunlight break it into smaller and smaller bits, but those bits don't turn into food. Animals can ea https://socialmedia.xdme.com/tony/videos-book6/page-130.mp4 https://www.youtube.com/embed/9rXisnDeyTA 127 2026-10-02T02:07:28+00:00 yes https://xdme.com/watch-book6-q131.html https://xdme.com/book6-thumbs/page-131.jpg Why Do Helpers Cut Six-Pack Rings? Plastic six-pack rings are loops that can trap animals. A loop can slip over a bird's neck or a turtle's flipper, and it can tighten as the animal grows. Cutting every loop removes https://socialmedia.xdme.com/tony/videos-book6/page-131.mp4 https://www.youtube.com/embed/5cocU5YM_II 121 2026-10-02T02:34:24+00:00 yes https://xdme.com/watch-book6-q132.html https://xdme.com/book6-thumbs/page-132.jpg Why Do Sea Turtles Eat Bags? Sea turtles eat jellyfish. A pale plastic bag floating in the water can look a lot like one. But a bag can block a turtle's gut, and that can make the turtle very sick. https://socialmedia.xdme.com/tony/videos-book6/page-132.mp4 https://www.youtube.com/embed/7sWh75csEZc 119 2026-10-02T02:49:59+00:00 yes https://xdme.com/watch-book6-q133.html https://xdme.com/book6-thumbs/page-133.jpg Why Is Oil in Water So Hard to Clean? Oil and water don't mix. Spilled oil floats, spreads into a thin film, and gets pushed around by wind. It sticks to feathers and marsh grass. https://socialmedia.xdme.com/tony/videos-book6/page-133.mp4 https://www.youtube.com/embed/UFWeB4abqMc 124 2026-10-02T03:19:37+00:00 yes https://xdme.com/watch-book6-q134.html https://xdme.com/book6-thumbs/page-134.jpg Why Do Beaches Need a Cleanup Day? The tide drops new trash on the beach, again and again. It is like a delivery service nobody ordered. A cleanup day is when many people pick up litter with bags and gloves, so the https://socialmedia.xdme.com/tony/videos-book6/page-134.mp4 https://www.youtube.com/embed/pEnjjqxBKbw 122 2026-10-02T03:43:41+00:00 yes https://xdme.com/watch-book6-q135.html https://xdme.com/book6-thumbs/page-135.jpg Why Do Some Sunscreens Hurt Reefs? Some chemical filters in sunscreen wash off swimmers and into the water. A coral reef is a living neighborhood of tiny animals. On a reef that's already stressed, those chemicals c https://socialmedia.xdme.com/tony/videos-book6/page-135.mp4 https://www.youtube.com/embed/YYZbVE4MnLE 123 2026-10-02T04:25:09+00:00 yes https://xdme.com/watch-book6-q136.html https://xdme.com/book6-thumbs/page-136.jpg Why Do We Measure the Ocean's Temperature? The ocean is like Earth's giant thermometer. Ships, buoys, satellites, and diving robots all take its temperature. One reading is a snapshot, but many readings tell a story. https://socialmedia.xdme.com/tony/videos-book6/page-136.mp4 https://www.youtube.com/embed/XnvPdd-yQRg 127 2026-10-02T05:02:58+00:00 yes https://xdme.com/watch-book6-q137.html https://xdme.com/book6-thumbs/page-137.jpg Why Is Sea Level Rising? Sea level is rising for two main reasons. First, warm water takes up a little more room, which is called thermal expansion. Second, ice on land melts and adds extra water to the se https://socialmedia.xdme.com/tony/videos-book6/page-137.mp4 https://www.youtube.com/embed/HTzZ6b0WRUA 126 2026-10-02T05:44:49+00:00 yes https://xdme.com/watch-book6-q138.html https://xdme.com/book6-thumbs/page-138.jpg Why Do Ice Sheets Matter to a Beach Far Away? Greenland and Antarctica hold huge ice sheets on land. When that ice melts or slides into the sea, it adds water to the whole ocean, because the ocean is one connected bowl. So a f https://socialmedia.xdme.com/tony/videos-book6/page-138.mp4 https://www.youtube.com/embed/XBEiD_zIC10 122 2026-10-02T06:01:23+00:00 yes https://xdme.com/watch-book6-q139.html https://xdme.com/book6-thumbs/page-139.jpg Why Does Extra Carbon Dioxide Change Seawater? The ocean drinks in some of the extra carbon dioxide that we put in the air by burning fuel. Carbon dioxide and water make a weak acid, so the sea becomes a little less basic. Scie https://socialmedia.xdme.com/tony/videos-book6/page-139.mp4 https://www.youtube.com/embed/7pxb5TDz81s 133 2026-10-02T06:49:08+00:00 yes https://xdme.com/watch-book6-q140.html https://xdme.com/book6-thumbs/page-140.jpg Why Do Scientists Tag Fish and Turtles? You can't follow a turtle across the ocean on a bike! So scientists use small tags and satellite packs, so animals can report where they feed, nest, and hide. A tag is like a postc https://socialmedia.xdme.com/tony/videos-book6/page-140.mp4 https://www.youtube.com/embed/xg84bIEA_as 125 2026-10-02T07:08:06+00:00 yes https://xdme.com/watch-book6-q141.html https://xdme.com/book6-thumbs/page-141.jpg Why Is a Marine Park a Kind of Fence? A marine park, or marine reserve, marks off a part of the sea where fishing, anchoring, or collecting is limited or stopped. The fence isn't made of boards. It's made of rules! https://socialmedia.xdme.com/tony/videos-book6/page-141.mp4 https://www.youtube.com/embed/zI7o5wTYrqk 128 2026-10-02T07:27:30+00:00 yes https://xdme.com/watch-book6-q142.html https://xdme.com/book6-thumbs/page-142.jpg Why Do Fishers Use Limits and Seasons? A limit caps how many fish a boat may keep. A season closes the water during spawning, when fish are making babies. Both leave breeders in the water, so there are still fish later. https://socialmedia.xdme.com/tony/videos-book6/page-142.mp4 https://www.youtube.com/embed/9w75YBh2lKU 125 2026-10-02T07:43:14+00:00 yes https://xdme.com/watch-book6-q143.html https://xdme.com/book6-thumbs/page-143.jpg Why Should You Put a Shell Back If a Creature Is Inside? A pretty shell on the beach might have a snail, a hermit crab, or a clam inside. Taking it home means taking a living animal away from its home in the sea. That pretty house is sti https://socialmedia.xdme.com/tony/videos-book6/page-143.mp4 https://www.youtube.com/embed/gkDBM61fWm4 118 2026-10-02T07:58:32+00:00 yes https://xdme.com/watch-book6-q144.html https://xdme.com/book6-thumbs/page-144.jpg Why Is Dumping Aquarium Fish in the Sea a Bad Idea? Aquarium fish, plants, and snails can survive and breed in places they don't belong. If they escape into the wild, they can crowd out the native animals. A tank pet can become a wi https://socialmedia.xdme.com/tony/videos-book6/page-144.mp4 https://www.youtube.com/embed/MD7WbKOy1yI 121 2026-10-02T08:11:29+00:00 yes https://xdme.com/watch-book6-q145.html https://xdme.com/book6-thumbs/page-145.jpg Why Do Ships Have Rules About Ballast Water? Ships take in ballast water to stay balanced, and let it out later. That water can carry tiny animals, plants, and larvae across the ocean. A ship's belly can sneak a whole zoo fro https://socialmedia.xdme.com/tony/videos-book6/page-145.mp4 https://www.youtube.com/embed/bjEmc9CZy9c 121 2026-10-02T08:28:06+00:00 yes https://xdme.com/watch-book6-q146.html https://xdme.com/book6-thumbs/page-146.jpg Why Do Some Coasts Restore Dunes? A dune is a sand hill held together by roots. It's a living wall that can grow back after a storm! Some towns plant beach grass and put up sand fences to help dunes rebuild. https://socialmedia.xdme.com/tony/videos-book6/page-146.mp4 https://www.youtube.com/embed/hu4HO7403h4 123 2026-10-02T08:41:09+00:00 yes https://xdme.com/watch-book6-q147.html https://xdme.com/book6-thumbs/page-147.jpg Why Should a Tide-Pool Visit Be Look, Don't Poke? A tide pool is like a tiny bathtub neighborhood for anemones, crabs, and small fish. Poking or turning rocks can crush animals or dry them out. To them, fingers can be giant earthq https://socialmedia.xdme.com/tony/videos-book6/page-147.mp4 https://www.youtube.com/embed/oZCpM9ps7iM 123 2026-10-02T08:44:16+00:00 yes https://xdme.com/watch-book6-q148.html https://xdme.com/book6-thumbs/page-148.jpg Why Does Turning Off Extra Lights Help Hatchling Turtles? Baby sea turtles hatch at night and crawl toward the brightest, lowest horizon, which is usually the sea. But street lights and porch lights can confuse them and pull them inland i https://socialmedia.xdme.com/tony/videos-book6/page-148.mp4 https://www.youtube.com/embed/Uw9lVKE_KfQ 121 2026-10-02T09:03:34+00:00 yes https://xdme.com/watch-book6-q149.html https://xdme.com/book6-thumbs/page-149.jpg Why Do Kids' Small Habits Still Matter for the Ocean? Most ocean trash and chemicals start on land, on streets, in yards, and at picnic tables. Rain and wind carry leftovers into drains and rivers, and rivers flow to the sea. So small https://socialmedia.xdme.com/tony/videos-book6/page-149.mp4 https://www.youtube.com/embed/lt93bWN94_g 122 2026-10-02T09:27:34+00:00 yes https://xdme.com/watch-book6-q150.html https://xdme.com/book6-thumbs/page-150.jpg Why Is the Ocean Worth a Whole Expedition? The ocean makes rain, makes much of our oxygen, carries heat, and hides mountains and coral cities. It touches our weather, our food, and our stories. Our whole expedition has show https://socialmedia.xdme.com/tony/videos-book6/page-150.mp4 https://www.youtube.com/embed/Z-3AUlshLoU 126 2026-10-02T09:32:36+00:00 yes https://xdme.com/watch-book7-q001.html https://xdme.com/book7-thumbs/page-001.jpg Why Do Clouds Form in the Sky? A cloud is not a puffy pillow. It is billions of tiny water droplets floating together. The air around you always holds invisible water, called water vapor. https://socialmedia.xdme.com/tony/videos-book7/page-001.mp4 https://www.youtube.com/embed/vCi3baXVcd8 122 2026-10-02T16:09:47+00:00 yes https://xdme.com/watch-book7-q002.html https://xdme.com/book7-thumbs/page-002.jpg Why Are Some Clouds Fluffy and Some Flat? Clouds come in lots of shapes, and the shape is a clue about the air around them. Fluffy clouds are called cumulus and form where warm air rises in bubbles. Flat, gray blankets of https://socialmedia.xdme.com/tony/videos-book7/page-002.mp4 https://www.youtube.com/embed/mm4kXd50ydM 125 2026-10-02T10:23:48+00:00 yes https://xdme.com/watch-book7-q003.html https://xdme.com/book7-thumbs/page-003.jpg Why Do Clouds Look White? Sunlight looks white, but it is really a mix of every color of the rainbow. A cloud is full of tiny water droplets that bounce sunlight in every direction. Because all the colors b https://socialmedia.xdme.com/tony/videos-book7/page-003.mp4 https://www.youtube.com/embed/q-q3hkFR33Q 117 2026-10-02T10:28:51+00:00 yes https://xdme.com/watch-book7-q004.html https://xdme.com/book7-thumbs/page-004.jpg Why Do Storm Clouds Look Gray or Black? Storm clouds look dark because they are thick, tall, and packed with water droplets and ice. That much material blocks and scatters sunlight, so very little light gets through to t https://socialmedia.xdme.com/tony/videos-book7/page-004.mp4 https://www.youtube.com/embed/muQD0G_iVDU 116 2026-10-02T10:33:26+00:00 yes https://xdme.com/watch-book7-q005.html https://xdme.com/book7-thumbs/page-005.jpg Why Does Fog Hug the Ground? Fog is simply a cloud that touches the ground. It forms when the air near the ground cools enough for invisible water vapor to turn into tiny droplets. That is why you can walk rig https://socialmedia.xdme.com/tony/videos-book7/page-005.mp4 https://www.youtube.com/embed/zG6uwafz_sM 122 2026-10-02T10:38:30+00:00 yes https://xdme.com/watch-book7-q006.html https://xdme.com/book7-thumbs/page-006.jpg Why Is Fog Thicker in the Morning? Fog is often thickest around sunrise, after the coldest part of the night. All night long the ground gives off heat and cools the air near it. By morning, that air can get cold eno https://socialmedia.xdme.com/tony/videos-book7/page-006.mp4 https://www.youtube.com/embed/vjtEg4QQxw4 117 2026-10-02T10:43:03+00:00 yes https://xdme.com/watch-book7-q007.html https://xdme.com/book7-thumbs/page-007.jpg Why Does Dew Sparkle on Grass? Dew is made of tiny beads of water that appear on grass overnight. At night the grass cools down, and invisible water vapor in the air touches it and turns into liquid droplets. Th https://socialmedia.xdme.com/tony/videos-book7/page-007.mp4 https://www.youtube.com/embed/5vGxdCjTF7g 118 2026-10-02T10:45:36+00:00 yes https://xdme.com/watch-book7-q008.html https://xdme.com/book7-thumbs/page-008.jpg Why Does Rain Fall as Drops, Not One Big Splash? Inside a cloud there are millions of tiny droplets that are too light to fall. They bump into each other and join up, growing bigger and bigger. Once a drop is heavy enough, it fal https://socialmedia.xdme.com/tony/videos-book7/page-008.mp4 https://www.youtube.com/embed/a2DdGuNWnqY 118 2026-10-02T10:52:11+00:00 yes https://xdme.com/watch-book7-q009.html https://xdme.com/book7-thumbs/page-009.jpg Why Do Raindrops Look Like Teardrops in Cartoons? In cartoons, raindrops have a pointy top and a round bottom, like a teardrop. But real falling raindrops are shaped more like rounded hamburger buns. The teardrop is art, not physi https://socialmedia.xdme.com/tony/videos-book7/page-009.mp4 https://www.youtube.com/embed/3oM702wN3XM 121 2026-10-02T10:55:15+00:00 yes https://xdme.com/watch-book7-q010.html https://xdme.com/book7-thumbs/page-010.jpg Why Does Drizzle Feel Different From a Downpour? Drizzle and downpours are both rain, but the drops are very different sizes. Drizzle drops are tiny and light, so they float down gently. Downpour drops are bigger and heavier, and https://socialmedia.xdme.com/tony/videos-book7/page-010.mp4 https://www.youtube.com/embed/zb9zZWeTc1k 119 2026-10-02T11:01:21+00:00 yes https://xdme.com/watch-book7-q011.html https://xdme.com/book7-thumbs/page-011.jpg Why Does Rain Smell So Good After a Dry Spell? That fresh smell after rain is called petrichor. It comes from oils made by plants and tiny living things in the soil. When raindrops hit dry ground, they puff those scents into th https://socialmedia.xdme.com/tony/videos-book7/page-011.mp4 https://www.youtube.com/embed/ZaMq6Im57q8 119 2026-10-02T11:06:54+00:00 yes https://xdme.com/watch-book7-q012.html https://xdme.com/book7-thumbs/page-012.jpg Why Do Puddles Form and Then Disappear? A puddle forms where rain collects faster than the ground can soak it up. Then it disappears in two ways: some water seeps down into the soil, and some evaporates into the air as i https://socialmedia.xdme.com/tony/videos-book7/page-012.mp4 https://www.youtube.com/embed/_XZmDVLznoI 126 2026-10-02T11:12:27+00:00 yes https://xdme.com/watch-book7-q013.html https://xdme.com/book7-thumbs/page-013.jpg Why Does Water Drip From Leaves After Rain? Leaves catch rain like tiny umbrellas, and they hold on to a lot of water. After the rain stops, the stored water slowly slides off in drips. It is like a second rain, coming from https://socialmedia.xdme.com/tony/videos-book7/page-013.mp4 https://www.youtube.com/embed/BWchUreL4kQ 120 2026-10-02T11:23:03+00:00 yes https://xdme.com/watch-book7-q014.html https://xdme.com/book7-thumbs/page-014.jpg Why Can You See Your Breath on a Cold Day? Your breath is warm and full of invisible water vapor from inside your body. On a cold day, that warm air meets chilly air right outside your mouth. The vapor cools quickly and tur https://socialmedia.xdme.com/tony/videos-book7/page-014.mp4 https://www.youtube.com/embed/tUGlqbyy0uo 118 2026-10-02T11:25:36+00:00 yes https://xdme.com/watch-book7-q015.html https://xdme.com/book7-thumbs/page-015.jpg Why Does Steam Rise From a Hot Sidewalk After Rain? When rain falls on hot pavement, the water can start to rise again right away. The sidewalk is much warmer than the rain, so the leftover water heats up quickly. It turns into vapo https://socialmedia.xdme.com/tony/videos-book7/page-015.mp4 https://www.youtube.com/embed/hGF8OLAC1U4 128 2026-10-02T11:38:42+00:00 yes https://xdme.com/watch-book7-q016.html https://xdme.com/book7-thumbs/page-016.jpg Why Do Mountains Make Their Own Clouds? Mountains can build clouds all on their own. When wind meets a mountain, the air has nowhere to go but up. As it rises, it cools, and that makes a cloud. https://socialmedia.xdme.com/tony/videos-book7/page-016.mp4 https://www.youtube.com/embed/7mVPgnPIpYo 116 2026-10-02T11:41:13+00:00 yes https://xdme.com/watch-book7-q017.html https://xdme.com/book7-thumbs/page-017.jpg Why Is There Fog Near Lakes and Rivers? Lakes and rivers keep adding invisible water vapor to the air above them. When cool night air settles over that moist air, the vapor can turn into tiny droplets. That wraps the sho https://socialmedia.xdme.com/tony/videos-book7/page-017.mp4 https://www.youtube.com/embed/JUzkGiGH3KA 119 2026-10-02T11:52:19+00:00 yes https://xdme.com/watch-book7-q018.html https://xdme.com/book7-thumbs/page-018.jpg Why Do Some Days Feel Sticky Before It Rains? Before many storms, the air is full of water vapor, so the humidity is high. When the air is that damp, your sweat has a hard time drying off. That leftover moisture on your skin i https://socialmedia.xdme.com/tony/videos-book7/page-018.mp4 https://www.youtube.com/embed/sBLb29mhlMQ 121 2026-10-02T11:54:51+00:00 yes https://xdme.com/watch-book7-q019.html https://xdme.com/book7-thumbs/page-019.jpg Why Does Hail Fall as Icy Balls? Hail is a ball of ice that forms inside a thunderstorm. Strong winds that blow upward, called updrafts, toss raindrops high into freezing air. That is why hail falls as icy balls, https://socialmedia.xdme.com/tony/videos-book7/page-019.mp4 https://www.youtube.com/embed/xCYuhGxiZgQ 121 2026-10-02T12:14:28+00:00 yes https://xdme.com/watch-book7-q020.html https://xdme.com/book7-thumbs/page-020.jpg Why Does Sleet Bounce and Snow Float? Sleet and snow both fall in cold weather, but they feel very different. Sleet is made of small, hard pellets of ice, so it bounces. Snowflakes are fluffy crystals that hold air, so https://socialmedia.xdme.com/tony/videos-book7/page-020.mp4 https://www.youtube.com/embed/3l9JopXSxpM 122 2026-10-02T12:16:59+00:00 yes https://xdme.com/watch-book7-q021.html https://xdme.com/book7-thumbs/page-021.jpg Why Does Frost Paint Windows? On very cold mornings, windows can wake up covered in ferny, feathery patterns. That is frost, and it is made by invisible water vapor in the air. The vapor turns straight into ice https://socialmedia.xdme.com/tony/videos-book7/page-021.mp4 https://www.youtube.com/embed/WmcI2xa50GE 124 2026-10-02T13:00:37+00:00 yes https://xdme.com/watch-book7-q022.html https://xdme.com/book7-thumbs/page-022.jpg Why Do Clouds Sometimes Look Like Animals? When you see a cloud shaped like a dragon, your brain is doing something clever. Brains love finding faces and animals in random shapes. This is called pareidolia. https://socialmedia.xdme.com/tony/videos-book7/page-022.mp4 https://www.youtube.com/embed/2_zqrV2VrmM 119 2026-10-02T13:02:38+00:00 yes https://xdme.com/watch-book7-q023.html https://xdme.com/book7-thumbs/page-023.jpg Why Can Airplanes Fly Through Clouds? A cloud looks like a solid pillow, but it is not solid at all. It is mostly air, with tiny droplets spaced far apart. So a plane can slip right through, like walking through a mist https://socialmedia.xdme.com/tony/videos-book7/page-023.mp4 https://www.youtube.com/embed/1eJo31GdiMU 120 2026-10-02T13:26:16+00:00 yes https://xdme.com/watch-book7-q024.html https://xdme.com/book7-thumbs/page-024.jpg Why Do Weather Balloons Go So High? Weather balloons carry little sensors called radiosondes up into the sky. They rise far above the clouds, into thin air, to measure temperature, humidity, and wind. Forecasters use https://socialmedia.xdme.com/tony/videos-book7/page-024.mp4 https://www.youtube.com/embed/fkxY-izhiqg 124 2026-10-02T13:28:17+00:00 yes https://xdme.com/watch-book7-q025.html https://xdme.com/book7-thumbs/page-025.jpg Why Do Scientists Name Cloud Types in Latin? Scientists around the world study clouds, but they speak many different languages. So they use Latin names, like cumulus, stratus, and cirrus, that anyone can share. It works like https://socialmedia.xdme.com/tony/videos-book7/page-025.mp4 https://www.youtube.com/embed/pn2Cyk-oq2s 127 2026-10-02T13:49:54+00:00 yes https://xdme.com/watch-book7-q026.html https://xdme.com/book7-thumbs/page-026.jpg Why Do Thunderstorms Build So Fast? On a hot, humid afternoon, a calm blue sky can turn into a thunderstorm in less than an hour. Hot, moist air rockets upward, and it cools as it rises. Scientists call that unstable https://socialmedia.xdme.com/tony/videos-book7/page-026.mp4 https://www.youtube.com/embed/pJT3T83LjFA 124 2026-10-02T13:51:55+00:00 yes https://xdme.com/watch-book7-q027.html https://xdme.com/book7-thumbs/page-027.jpg Why Does Thunder Rumble After Lightning? Lightning and thunder happen at exactly the same moment. But you see the flash first and hear the boom later. That is because light travels much faster than sound. https://socialmedia.xdme.com/tony/videos-book7/page-027.mp4 https://www.youtube.com/embed/EWo3z7sSth0 121 2026-10-02T14:17:02+00:00 yes https://xdme.com/watch-book7-q028.html https://xdme.com/book7-thumbs/page-028.jpg Why Is Lightning So Bright? A flash of lightning can light up the whole sky, even in the middle of the night. That is because the lightning channel gets incredibly hot, hotter than the surface of the Sun. Ver https://socialmedia.xdme.com/tony/videos-book7/page-028.mp4 https://www.youtube.com/embed/SV0H0Jb2kw0 122 2026-10-02T14:19:34+00:00 yes https://xdme.com/watch-book7-q029.html https://xdme.com/book7-thumbs/page-029.jpg Why Does Lightning Zigzag? Lightning never travels in a straight line. It zigzags and branches across the sky. That is because air is not the same everywhere, so electricity finds its way in short steps. https://socialmedia.xdme.com/tony/videos-book7/page-029.mp4 https://www.youtube.com/embed/UY6UowpRTwU 121 2026-10-02T14:45:40+00:00 yes https://xdme.com/watch-book7-q030.html https://xdme.com/book7-thumbs/page-030.jpg Why Do We Count Seconds After a Flash? Counting the seconds between a flash of lightning and the boom of thunder tells you how far away the storm is. That helps you know if the storm is coming closer or moving away. It https://socialmedia.xdme.com/tony/videos-book7/page-030.mp4 https://www.youtube.com/embed/xy9k4asYuRo 119 2026-10-02T14:47:41+00:00 yes https://xdme.com/watch-book7-q031.html https://xdme.com/book7-thumbs/page-031.jpg Why Is Metal Not a Lightning Magnet the Way Myths Say? Many people believe metal pulls lightning toward it like a magnet, but that is a myth. Metal does not attract lightning. What matters most is how tall something is and how easy a p https://socialmedia.xdme.com/tony/videos-book7/page-031.mp4 https://www.youtube.com/embed/b9nCgjNQsX4 121 2026-10-02T15:14:18+00:00 yes https://xdme.com/watch-book7-q032.html https://xdme.com/book7-thumbs/page-032.jpg Why Do Tall Trees and Towers Get Struck More Often? Lightning often hits the tallest handy point. Tall trees and towers stick up into the part of the sky where the storm's electricity is. That gives lightning a shorter, easier path https://socialmedia.xdme.com/tony/videos-book7/page-032.mp4 https://www.youtube.com/embed/TSc5gZKX5xA 121 2026-10-02T15:16:20+00:00 yes https://xdme.com/watch-book7-q033.html https://xdme.com/book7-thumbs/page-033.jpg Why Is a Car Usually Safer in a Storm (But Not Always)? A hard-topped car with its windows up can protect you from lightning, but only sometimes. If lightning strikes it, the metal shell helps carry the electricity around the outside. T https://socialmedia.xdme.com/tony/videos-book7/page-033.mp4 https://www.youtube.com/embed/5g7cENPQpUk 121 2026-10-02T15:37:57+00:00 yes https://xdme.com/watch-book7-q034.html https://xdme.com/book7-thumbs/page-034.jpg Why Should You Avoid Open Fields in Lightning? An open field has no tall buildings or trees, so a person standing in it becomes one of the tallest things around. That makes you a risky target for lightning. Flat and lonely is b https://socialmedia.xdme.com/tony/videos-book7/page-034.mp4 https://www.youtube.com/embed/homY1YuVYcQ 119 2026-10-02T15:39:58+00:00 yes https://xdme.com/watch-book7-q035.html https://xdme.com/book7-thumbs/page-035.jpg Why Does Thunder Shake Windows? Thunder is a sound, and sound is a wave that pushes on the air. A loud, close thunderclap pushes hard enough to make windows rattle. Windows shaking is just energy traveling throug https://socialmedia.xdme.com/tony/videos-book7/page-035.mp4 https://www.youtube.com/embed/o3SyE14PYps 119 2026-10-02T16:09:51+00:00 yes https://xdme.com/watch-book7-q036.html https://xdme.com/book7-thumbs/page-036.jpg Why Do Some Storms Make Hail the Size of Marbles? Some thunderstorms make hail as big as marbles, or even bigger. That happens when the storm has very strong updrafts that keep ice floating high up for longer. The longer a hailsto https://socialmedia.xdme.com/tony/videos-book7/page-036.mp4 https://www.youtube.com/embed/H8AeHPhX2po 122 2026-10-02T16:09:52+00:00 yes https://xdme.com/watch-book7-q037.html https://xdme.com/book7-thumbs/page-037.jpg Why Do Tornadoes Spin? A tornado is a spinning column of air that reaches from a storm cloud to the ground. It starts with winds that blow in different directions at different heights. Under the right co https://socialmedia.xdme.com/tony/videos-book7/page-037.mp4 https://www.youtube.com/embed/x1kLftKJBwA 123 2026-10-02T16:12:05+00:00 yes https://xdme.com/watch-book7-q038.html https://xdme.com/book7-thumbs/page-038.jpg Why Is a Tornado Watch Different From a Warning? A tornado watch and a tornado warning sound alike, but they mean very different things. A watch means a tornado could happen, so be ready. A warning means one is happening or about https://socialmedia.xdme.com/tony/videos-book7/page-038.mp4 https://www.youtube.com/embed/PrSKqksKYf8 120 2026-10-02T16:15:06+00:00 yes https://xdme.com/watch-book7-q039.html https://xdme.com/book7-thumbs/page-039.jpg Why Do Hurricanes Have an “Eye”? A hurricane is a giant spinning storm made of clouds, wind, and rain. In the very middle, there is a calm spot called the eye. Air sinks there, so the clouds clear and the winds di https://socialmedia.xdme.com/tony/videos-book7/page-039.mp4 https://www.youtube.com/embed/fHfgIJ-sSzM 140 2026-10-02T10:16:42+00:00 yes https://xdme.com/watch-book7-q040.html https://xdme.com/book7-thumbs/page-040.jpg Why Do Hurricanes Need Warm Ocean Water? A hurricane is like an engine, and warm ocean water is its fuel. The sea has to be about 26 degrees Celsius, or 80 degrees Fahrenheit, or warmer, and that warm water has to go down https://socialmedia.xdme.com/tony/videos-book7/page-040.mp4 https://www.youtube.com/embed/zuY53W8XvfY 134 2026-10-02T10:19:14+00:00 yes https://xdme.com/watch-book7-q041.html https://xdme.com/book7-thumbs/page-041.jpg Why Do Storm Names Get Retired? Strong storms get names so people can talk about them quickly and clearly. If a storm causes terrible damage, its name is retired out of respect, like retiring a sports jersey. Tha https://socialmedia.xdme.com/tony/videos-book7/page-041.mp4 https://www.youtube.com/embed/c4HVw8ffEwI 120 2026-10-02T10:23:17+00:00 yes https://xdme.com/watch-book7-q042.html https://xdme.com/book7-thumbs/page-042.jpg Why Does the Sky Turn Greenish Before Some Storms? Sometimes the sky turns an eerie green before a strong storm. Huge, thick storm clouds scatter sunlight in odd ways, and that can tint the sky greenish. It is a clue that something https://socialmedia.xdme.com/tony/videos-book7/page-042.mp4 https://www.youtube.com/embed/NQhUtKhbWbM 124 2026-10-02T10:28:52+00:00 yes https://xdme.com/watch-book7-q043.html https://xdme.com/book7-thumbs/page-043.jpg Why Do Power Lines Go Out in Storms? Electricity travels along power lines on tall poles, and storms can hit those lines hard. Strong wind can knock down trees and poles, and lightning can send a surge through the wir https://socialmedia.xdme.com/tony/videos-book7/page-043.mp4 https://www.youtube.com/embed/6K_w3uJ8Z1c 127 2026-10-02T10:33:57+00:00 yes https://xdme.com/watch-book7-q044.html https://xdme.com/book7-thumbs/page-044.jpg Why Do Weather Sirens Howl? A weather siren is a giant outdoor loudspeaker. Its job is to warn people outside when dangerous weather is near, so they can get to shelter quickly. The howl means: take action no https://socialmedia.xdme.com/tony/videos-book7/page-044.mp4 https://www.youtube.com/embed/kudVdsv68RA 120 2026-10-02T10:38:30+00:00 yes https://xdme.com/watch-book7-q045.html https://xdme.com/book7-thumbs/page-045.jpg Why Is Shelter in a Basement Safer in a Tornado? In a tornado, the biggest danger is flying debris, like broken glass, boards, and branches. A basement or a low interior room puts more walls and floors between you and that debris https://socialmedia.xdme.com/tony/videos-book7/page-045.mp4 https://www.youtube.com/embed/OuJKveaP2-k 122 2026-10-02T10:41:02+00:00 yes https://xdme.com/watch-book7-q046.html https://xdme.com/book7-thumbs/page-046.jpg Why Do Flash Floods Happen So Quickly? A flash flood is a flood that arrives fast, with little warning. Very hard rain can fall faster than the ground and drains can soak it up, so the water has nowhere to go. Flash mea https://socialmedia.xdme.com/tony/videos-book7/page-046.mp4 https://www.youtube.com/embed/oU2vK7diOvk 126 2026-10-02T10:45:05+00:00 yes https://xdme.com/watch-book7-q047.html https://xdme.com/book7-thumbs/page-047.jpg Why Should You Never Drive Into Flooded Streets? Floodwater is much more powerful than it looks. Just about 30 centimeters, or about a foot, of moving water can float many cars. And you cannot see what is under the muddy water, s https://socialmedia.xdme.com/tony/videos-book7/page-047.mp4 https://www.youtube.com/embed/mXJ-2-beYU0 122 2026-10-02T10:48:08+00:00 yes https://xdme.com/watch-book7-q048.html https://xdme.com/book7-thumbs/page-048.jpg Why Do Blizzards Make It Hard to See? A blizzard is a snowstorm with strong winds and very low visibility. The wind blows snow around so much that the sky and the ground blend together into one white blur. That is call https://socialmedia.xdme.com/tony/videos-book7/page-048.mp4 https://www.youtube.com/embed/Llmc5EZiICA 119 2026-10-02T10:54:14+00:00 yes https://xdme.com/watch-book7-q049.html https://xdme.com/book7-thumbs/page-049.jpg Why Do Ice Storms Coat Everything in Glass? An ice storm happens when rain freezes the moment it touches something cold. It paints every branch, wire, and road with a smooth layer of ice that looks like glass. It is pretty, https://socialmedia.xdme.com/tony/videos-book7/page-049.mp4 https://www.youtube.com/embed/Ddeh29qM96w 117 2026-10-02T10:57:18+00:00 yes https://xdme.com/watch-book7-q050.html https://xdme.com/book7-thumbs/page-050.jpg Why Do Grown-Ups Say “When Thunder Roars, Go Indoors”? Thunder is the sound of lightning, so if you can hear thunder, lightning is close enough to be dangerous. Lightning can strike many kilometers away from the storm, even when the sk https://socialmedia.xdme.com/tony/videos-book7/page-050.mp4 https://www.youtube.com/embed/zf0G8tkyrEM 120 2026-10-02T11:03:23+00:00 yes https://xdme.com/watch-book7-q051.html https://xdme.com/book7-thumbs/page-051.jpg Why Does Wind Blow at All? Wind is simply air that is moving. The Sun heats the Earth unevenly, so some places warm up fast and others stay cooler. Air then moves from areas of high pressure to areas of low https://socialmedia.xdme.com/tony/videos-book7/page-051.mp4 https://www.youtube.com/embed/dH09Xxu3irQ 115 2026-10-02T11:08:56+00:00 yes https://xdme.com/watch-book7-q052.html https://xdme.com/book7-thumbs/page-052.jpg Why Is a Breeze Soft and a Gale Strong? Wind is air moving from high pressure to low pressure. If the pressure difference is small, you feel a soft breeze. If the pressure difference is large, you get a gale, a strong wi https://socialmedia.xdme.com/tony/videos-book7/page-052.mp4 https://www.youtube.com/embed/oVgIb_41CXs 114 2026-10-02T11:15:00+00:00 yes https://xdme.com/watch-book7-q053.html https://xdme.com/book7-thumbs/page-053.jpg Why Do Flags Flap and Pinwheels Spin? You can't see wind, but you can see what it does. Moving air pushes on a flag's fabric and on a pinwheel's blades, so they flap and spin. Flags and pinwheels are wind translators t https://socialmedia.xdme.com/tony/videos-book7/page-053.mp4 https://www.youtube.com/embed/i58ugaa22Nc 115 2026-10-02T11:25:05+00:00 yes https://xdme.com/watch-book7-q054.html https://xdme.com/book7-thumbs/page-054.jpg Why Do We Feel Wind More on Hills and Beaches? Wind feels stronger on hills and beaches because there is less in its way. Cities and forests slow the wind down with buildings and trees. Open water and hilltops have almost nothi https://socialmedia.xdme.com/tony/videos-book7/page-054.mp4 https://www.youtube.com/embed/CWk6g-tb-KU 122 2026-10-02T11:27:37+00:00 yes https://xdme.com/watch-book7-q055.html https://xdme.com/book7-thumbs/page-055.jpg Why Does Wind Have Directions Like North and West? We name wind by where it comes from, not where it is going. A north wind blows from the north toward the south. It is like labeling a letter with the sender's address, not the addr https://socialmedia.xdme.com/tony/videos-book7/page-055.mp4 https://www.youtube.com/embed/SCOKHfqtbkg 110 2026-10-02T11:41:15+00:00 yes https://xdme.com/watch-book7-q056.html https://xdme.com/book7-thumbs/page-056.jpg Why Do Weather Vanes Point Into the Wind? A weather vane is an old-fashioned wind detector that sits on a roof or barn. It spins freely, and the pointer end turns to face into the oncoming wind. So the arrow always points https://socialmedia.xdme.com/tony/videos-book7/page-056.mp4 https://www.youtube.com/embed/pj4TawhWf_Y 112 2026-10-02T11:43:16+00:00 yes https://xdme.com/watch-book7-q057.html https://xdme.com/book7-thumbs/page-057.jpg Why Does High Pressure Often Mean Fair Weather? High pressure often means fair weather. In a high-pressure area, the air is sinking, and sinking air discourages clouds from growing. That usually means clearer skies and calmer we https://socialmedia.xdme.com/tony/videos-book7/page-057.mp4 https://www.youtube.com/embed/CoYicp1ZCSk 112 2026-10-02T11:54:52+00:00 yes https://xdme.com/watch-book7-q058.html https://xdme.com/book7-thumbs/page-058.jpg Why Does Low Pressure Often Mean Storms? Low pressure often means stormier weather. In a low-pressure area, air is rising, and rising air cools and builds clouds. That gives you better chances for rain, wind, and storms. https://socialmedia.xdme.com/tony/videos-book7/page-058.mp4 https://www.youtube.com/embed/gwClRDu1698 115 2026-10-02T16:28:12+00:00 yes https://xdme.com/watch-book7-q059.html https://xdme.com/book7-thumbs/page-059.jpg Why Do Isobars Look Like Squiggly Lines on Maps? Isobars are lines on a weather map that connect places with the same air pressure. Pressure changes from place to place in curvy ways, so the lines wiggle and curl, just like the l https://socialmedia.xdme.com/tony/videos-book7/page-059.mp4 https://www.youtube.com/embed/huS4mHfSO4I 116 2026-10-02T12:19:00+00:00 yes https://xdme.com/watch-book7-q060.html https://xdme.com/book7-thumbs/page-060.jpg Why Do H and L Letters Appear on Weather Maps? On a weather map, a big H marks the center of an area of high pressure. A big L marks the center of an area of low pressure. They are the main characters in the weather story, and https://socialmedia.xdme.com/tony/videos-book7/page-060.mp4 https://www.youtube.com/embed/8YgBlDAhdY8 111 2026-10-02T12:21:31+00:00 yes https://xdme.com/watch-book7-q061.html https://xdme.com/book7-thumbs/page-061.jpg Why Do Fronts Look Like Triangles and Semicircles? A front is the boundary between two different air masses, one cold and one warm. On weather maps, fronts are drawn with a line and little shapes. Cold fronts get blue triangles, an https://socialmedia.xdme.com/tony/videos-book7/page-061.mp4 https://www.youtube.com/embed/TtvrkCq1aGk 119 2026-10-02T13:07:09+00:00 yes https://xdme.com/watch-book7-q062.html https://xdme.com/book7-thumbs/page-062.jpg Why Does a Cold Front Often Bring Sudden Showers? A cold front is where cold air pushes into a warmer area. Cold air is heavier, so it shoves under the warm air and lifts it upward quickly. That fast lift can pop up sudden showers https://socialmedia.xdme.com/tony/videos-book7/page-062.mp4 https://www.youtube.com/embed/nYBVU3t5b2Y 117 2026-10-02T13:09:11+00:00 yes https://xdme.com/watch-book7-q063.html https://xdme.com/book7-thumbs/page-063.jpg Why Does a Warm Front Bring Longer, Gentler Rain? A warm front is where warm air slowly moves in over cooler air. Warm air is lighter, so it glides up over the cool air like a gentle ramp. That slow slope makes wide sheets of clou https://socialmedia.xdme.com/tony/videos-book7/page-063.mp4 https://www.youtube.com/embed/eWOe_HKLHks 114 2026-10-02T13:32:48+00:00 yes https://xdme.com/watch-book7-q064.html https://xdme.com/book7-thumbs/page-064.jpg Why Do Jet Streams Race High Above Us? Jet streams are fast rivers of wind high up in the sky. They blow about 9 to 12 kilometers above the ground, which is where airplanes cruise. They steer storms like highways in the https://socialmedia.xdme.com/tony/videos-book7/page-064.mp4 https://www.youtube.com/embed/eFKlt-JqM3w 113 2026-10-02T13:34:49+00:00 yes https://xdme.com/watch-book7-q065.html https://xdme.com/book7-thumbs/page-065.jpg Why Do Airplanes Care About Wind? Airplanes fly through moving air, so wind matters a lot to them. A tailwind pushes a plane from behind and speeds the trip. A headwind pushes against it and slows it down. https://socialmedia.xdme.com/tony/videos-book7/page-065.mp4 https://www.youtube.com/embed/ucV4Vfz0mMA 121 2026-10-02T13:58:27+00:00 yes https://xdme.com/watch-book7-q066.html https://xdme.com/book7-thumbs/page-066.jpg Why Does Wind Chill Make You Feel Colder? Wind chill is how cold the air feels on your skin when the wind is blowing. Wind steals heat from your skin faster, so the same temperature feels colder. The air itself is not cold https://socialmedia.xdme.com/tony/videos-book7/page-066.mp4 https://www.youtube.com/embed/lBEByvL8MqM 119 2026-10-02T14:01:28+00:00 yes https://xdme.com/watch-book7-q067.html https://xdme.com/book7-thumbs/page-067.jpg Why Do Deserts Get Hot Days and Cold Nights? Deserts can be scorching hot during the day and surprisingly cold at night. Dry air and clear skies let heat escape into space after sunset. So the temperature can swing by 20 degr https://socialmedia.xdme.com/tony/videos-book7/page-067.mp4 https://www.youtube.com/embed/a1tgGYkqRuA 119 2026-10-02T14:26:05+00:00 yes https://xdme.com/watch-book7-q068.html https://xdme.com/book7-thumbs/page-068.jpg Why Do Cities Feel Warmer than Countryside? Cities are often warmer than the countryside around them. Pavement, roofs, and buildings soak up the Sun's heat and release it slowly in the evening. Scientists call this the urban https://socialmedia.xdme.com/tony/videos-book7/page-068.mp4 https://www.youtube.com/embed/-LiA-y52yxU 119 2026-10-02T14:28:36+00:00 yes https://xdme.com/watch-book7-q069.html https://xdme.com/book7-thumbs/page-069.jpg Why Do We Measure Wind in Knots or Mph? Wind speed can be measured in different units, just like distance can be measured in kilometers or miles. On land, many places use miles per hour or kilometers per hour. Sailors an https://socialmedia.xdme.com/tony/videos-book7/page-069.mp4 https://www.youtube.com/embed/4ZRUhkAIHew 125 2026-10-02T14:54:43+00:00 yes https://xdme.com/watch-book7-q070.html https://xdme.com/book7-thumbs/page-070.jpg Why Do Anemometers Spin? An anemometer is a tool that measures how fast the wind is blowing. A common kind has three or four little cups on arms. The wind catches the cups and makes them spin. https://socialmedia.xdme.com/tony/videos-book7/page-070.mp4 https://www.youtube.com/embed/9ue139bNgzQ 114 2026-10-02T14:56:43+00:00 yes https://xdme.com/watch-book7-q071.html https://xdme.com/book7-thumbs/page-071.jpg Why Do Barometers Help Forecast? A barometer is a tool that measures air pressure. Air pressure goes up and down as weather systems move in and out. Watching the pressure rise or fall gives hints about what weathe https://socialmedia.xdme.com/tony/videos-book7/page-071.mp4 https://www.youtube.com/embed/-TotgmZvMMk 113 2026-10-02T15:20:51+00:00 yes https://xdme.com/watch-book7-q072.html https://xdme.com/book7-thumbs/page-072.jpg Why Do Weather Apps Show Different Numbers? Two weather apps can show different numbers for the same time and place. That is because they can use different computer models, different weather stations, and different update ti https://socialmedia.xdme.com/tony/videos-book7/page-072.mp4 https://www.youtube.com/embed/A2lY2t_Tdw4 116 2026-10-02T15:22:51+00:00 yes https://xdme.com/watch-book7-q073.html https://xdme.com/book7-thumbs/page-073.jpg Why Do Satellites Watch Earth From Space? Weather satellites are like cameras and thermometers in space, looking down at the Earth. From high above, they can see huge storms, clouds, and temperatures all at once. They are https://socialmedia.xdme.com/tony/videos-book7/page-073.mp4 https://www.youtube.com/embed/h97StvFwhEo 118 2026-10-02T15:44:29+00:00 yes https://xdme.com/watch-book7-q074.html https://xdme.com/book7-thumbs/page-074.jpg Why Do Doppler Radars See Rain Before It Arrives? Doppler radar sends out pulses of radio waves and listens for the echoes that bounce back. Raindrops, hail, and snow bounce those waves back, so radar can see precipitation far awa https://socialmedia.xdme.com/tony/videos-book7/page-074.mp4 https://www.youtube.com/embed/ogLAdhM3Qkw 124 2026-10-02T16:09:55+00:00 yes https://xdme.com/watch-book7-q075.html https://xdme.com/book7-thumbs/page-075.jpg Why Do Meteorologists Still Go Outside? Meteorologists have amazing tools, like satellites, radar, and computers. But people still go outside to launch balloons, check instruments, and use their own eyes. That is because https://socialmedia.xdme.com/tony/videos-book7/page-075.mp4 https://www.youtube.com/embed/uJXdsA5tVNQ 122 2026-10-02T16:09:56+00:00 yes https://xdme.com/watch-book7-q076.html https://xdme.com/book7-thumbs/page-076.jpg Why Do We Have Seasons? We have seasons because the Earth is tilted as it travels around the Sun. The tilt changes how directly sunlight hits your part of the world as the year goes on. Direct sunlight me https://socialmedia.xdme.com/tony/videos-book7/page-076.mp4 https://www.youtube.com/embed/A5KDJJgBAFk 121 2026-10-02T16:09:58+00:00 yes https://xdme.com/watch-book7-q077.html https://xdme.com/book7-thumbs/page-077.jpg Why Is Summer Hotter than Winter Where You Live? Summer is hotter because of a tilt! Earth leans as it travels around the Sun. In summer, your part of the world leans toward the Sun, so light hits more directly and days last long https://socialmedia.xdme.com/tony/videos-book7/page-077.mp4 https://www.youtube.com/embed/Auj63NFqGF8 117 2026-10-02T10:20:44+00:00 yes https://xdme.com/watch-book7-q078.html https://xdme.com/book7-thumbs/page-078.jpg Why Are Seasons Flipped in the Other Hemisphere? Seasons are flipped because Earth is tilted, like a giant teeter-totter. When the north leans toward the Sun, the south leans away. So one side's summer is the other side's winter! https://socialmedia.xdme.com/tony/videos-book7/page-078.mp4 https://www.youtube.com/embed/P6FUqbj379k 122 2026-10-02T10:26:50+00:00 yes https://xdme.com/watch-book7-q079.html https://xdme.com/book7-thumbs/page-079.jpg Why Does the Sun Feel Stronger at Noon? The Sun feels stronger around noon because it is at its highest point in the sky. When the Sun is high, its light takes a shorter path through the air, so less light is lost along https://socialmedia.xdme.com/tony/videos-book7/page-079.mp4 https://www.youtube.com/embed/Hl0v7s4863A 122 2026-10-02T10:31:23+00:00 yes https://xdme.com/watch-book7-q080.html https://xdme.com/book7-thumbs/page-080.jpg Why Do Long Summer Days Feel Endless? Long summer days feel endless because the Sun really does stay up longer! Earth's tilt points your half of the world toward the Sun in summer, so the Sun is above the horizon for m https://socialmedia.xdme.com/tony/videos-book7/page-080.mp4 https://www.youtube.com/embed/vyumkWA0UqQ 120 2026-10-02T10:35:57+00:00 yes https://xdme.com/watch-book7-q081.html https://xdme.com/book7-thumbs/page-081.jpg Why Do Short Winter Days Feel Cozy and Dark? Winter days are short because your part of Earth is tilted away from the Sun. The Sun stays low and is up for fewer hours, so sunset comes early and darkness arrives sooner. That m https://socialmedia.xdme.com/tony/videos-book7/page-081.mp4 https://www.youtube.com/embed/UXWK1dF6Owg 125 2026-10-02T11:18:31+00:00 yes https://xdme.com/watch-book7-q082.html https://xdme.com/book7-thumbs/page-082.jpg Why Do Leaves Change Color in Autumn? Leaves change color in autumn because trees stop making green chlorophyll. Shorter days and cooler weather tell trees to get ready for winter. As the green fades, hidden yellows, o https://socialmedia.xdme.com/tony/videos-book7/page-082.mp4 https://www.youtube.com/embed/DLNbNcDcLCY 118 2026-10-02T10:50:09+00:00 yes https://xdme.com/watch-book7-q083.html https://xdme.com/book7-thumbs/page-083.jpg Why Do Some Places Stay Warm All Year? Some places stay warm all year because their location keeps the sunshine strong all year long. Near the equator, the Sun stays high in the sky, and warm oceans help keep the heat s https://socialmedia.xdme.com/tony/videos-book7/page-083.mp4 https://www.youtube.com/embed/Nu42Sqtr1Ms 123 2026-10-02T10:53:13+00:00 yes https://xdme.com/watch-book7-q084.html https://xdme.com/book7-thumbs/page-084.jpg Why Do the Poles Stay Cold? The poles stay cold because sunlight reaches them at a low angle, and they spend months in darkness. Weak, slanted sunlight plus long polar nights is a recipe for a freezer belt. W https://socialmedia.xdme.com/tony/videos-book7/page-084.mp4 https://www.youtube.com/embed/wsai7HJDDGk 131 2026-10-02T10:59:19+00:00 yes https://xdme.com/watch-book7-q085.html https://xdme.com/book7-thumbs/page-085.jpg Why Does the Equator Get So Much Heat? The equator gets so much heat because the Sun stays high in the sky there most of the year. High Sun means strong, direct sunshine, so Earth's middle gets a big dose of energy. It https://socialmedia.xdme.com/tony/videos-book7/page-085.mp4 https://www.youtube.com/embed/b802O__ngCo 119 2026-10-02T11:02:22+00:00 yes https://xdme.com/watch-book7-q086.html https://xdme.com/book7-thumbs/page-086.jpg Why Does Humidity Make Hot Days Feel Hotter? Humid air makes hot days feel hotter because it slows down your body's cooling system. When you sweat, the sweat evaporates and takes heat away from your skin. In very humid air, s https://socialmedia.xdme.com/tony/videos-book7/page-086.mp4 https://www.youtube.com/embed/ReFJqUkM0W4 117 2026-10-02T11:10:26+00:00 yes https://xdme.com/watch-book7-q087.html https://xdme.com/book7-thumbs/page-087.jpg Why Does Dry Air Make Cold Days Feel Sharper? Dry air makes cold days feel sharper because it pulls moisture out of your skin and lips. Cold air can't hold much water vapor, so winter air is often very dry. Dry, cold air can n https://socialmedia.xdme.com/tony/videos-book7/page-087.mp4 https://www.youtube.com/embed/s5218glAlAE 117 2026-10-02T11:20:32+00:00 yes https://xdme.com/watch-book7-q088.html https://xdme.com/book7-thumbs/page-088.jpg Why Do Heat Waves Stick Around? Heat waves stick around because of a stuck area of high pressure, sometimes called a heat dome. A high-pressure area can park over a region for days, and it keeps the hot air from https://socialmedia.xdme.com/tony/videos-book7/page-088.mp4 https://www.youtube.com/embed/V_FykxVQ5u8 123 2026-10-02T11:23:04+00:00 yes https://xdme.com/watch-book7-q089.html https://xdme.com/book7-thumbs/page-089.jpg Why Do Cold Snaps Arrive So Suddenly? Cold snaps arrive suddenly because a big mass of cold air can surge in behind a weather front. These cold air masses come from icy places, like near the poles or a snowy continent. https://socialmedia.xdme.com/tony/videos-book7/page-089.mp4 https://www.youtube.com/embed/YJBg-hnovWw 126 2026-10-02T11:34:40+00:00 yes https://xdme.com/watch-book7-q090.html https://xdme.com/book7-thumbs/page-090.jpg Why Does Snow Cover Keep the Ground Insulated? Snow keeps the ground insulated because fluffy snow traps lots of tiny pockets of air. Air is a poor conductor of heat, so a snow blanket slows heat from escaping the soil. Snow ca https://socialmedia.xdme.com/tony/videos-book7/page-090.mp4 https://www.youtube.com/embed/UZ4S_64Dlzk 125 2026-10-02T11:36:41+00:00 yes https://xdme.com/watch-book7-q091.html https://xdme.com/book7-thumbs/page-091.jpg Why Do Gardens Need Different Planting Months? Gardens need different planting months because plants need the right mix of warmth, light, and no frost. Every place has its own pattern of seasons, so planting calendars follow lo https://socialmedia.xdme.com/tony/videos-book7/page-091.mp4 https://www.youtube.com/embed/aCQbbTATUVI 121 2026-10-02T11:50:18+00:00 yes https://xdme.com/watch-book7-q092.html https://xdme.com/book7-thumbs/page-092.jpg Why Do Birds Migrate with the Seasons? Many birds migrate with the seasons to follow food and find safe weather for nesting. When winter makes insects and plants scarce, they travel to places with more food. Migration i https://socialmedia.xdme.com/tony/videos-book7/page-092.mp4 https://www.youtube.com/embed/hXbVZW8tws0 122 2026-10-02T11:52:50+00:00 yes https://xdme.com/watch-book7-q093.html https://xdme.com/book7-thumbs/page-093.jpg Why Do Bears and Other Animals Slow Down in Winter? Bears and other animals slow down in winter because food is scarce and cold weather costs a lot of energy. Slowing the body down saves energy, so they can survive until spring. Res https://socialmedia.xdme.com/tony/videos-book7/page-093.mp4 https://www.youtube.com/embed/jd4msNVJ0S4 121 2026-10-02T12:09:56+00:00 yes https://xdme.com/watch-book7-q094.html https://xdme.com/book7-thumbs/page-094.jpg Why Does Climate Mean More than Today’s Weather? Weather is what the sky is doing today, and it can change from hour to hour. Climate is the long-term pattern of weather in a place, averaged over many years. So one chilly day doe https://socialmedia.xdme.com/tony/videos-book7/page-094.mp4 https://www.youtube.com/embed/9rx5iqlX2Ow 120 2026-10-02T12:12:57+00:00 yes https://xdme.com/watch-book7-q095.html https://xdme.com/book7-thumbs/page-095.jpg Why Do Scientists Track Climate Over Many Years? Scientists track climate over many years because one lucky warm week can fool you. Long records show real trends, and they separate steady changes from random ups and downs. Patien https://socialmedia.xdme.com/tony/videos-book7/page-095.mp4 https://www.youtube.com/embed/UMX0EuVvoKE 124 2026-10-02T12:56:04+00:00 yes https://xdme.com/watch-book7-q096.html https://xdme.com/book7-thumbs/page-096.jpg Why Do Tree Rings and Ice Cores Hold Climate Clues? Tree rings and ice cores hold climate clues because they store a yearly record of the past. Each year, a tree adds a ring and the ice adds a layer, and both are shaped by that year https://socialmedia.xdme.com/tony/videos-book7/page-096.mp4 https://www.youtube.com/embed/dQ0fZl6sm0M 119 2026-10-02T12:58:36+00:00 yes https://xdme.com/watch-book7-q097.html https://xdme.com/book7-thumbs/page-097.jpg Why Can One Hot Day Not Prove the Climate Is Changing? One hot day can't prove the climate is changing because one day is just weather. Weather jumps up and down naturally, so scientists look for long patterns across many places and ma https://socialmedia.xdme.com/tony/videos-book7/page-097.mp4 https://www.youtube.com/embed/xyjRh3GS9B0 121 2026-10-02T13:22:14+00:00 yes https://xdme.com/watch-book7-q098.html https://xdme.com/book7-thumbs/page-098.jpg Why Do Oceans Store So Much Heat? Oceans store so much heat because water can hold a huge amount of heat energy. They soak up energy from the Sun and release it slowly, which shapes climates around the world. Ocean https://socialmedia.xdme.com/tony/videos-book7/page-098.mp4 https://www.youtube.com/embed/RLY4gxL8pSg 124 2026-10-02T13:24:15+00:00 yes https://xdme.com/watch-book7-q099.html https://xdme.com/book7-thumbs/page-099.jpg Why Do Volcanoes Temporarily Cool the Planet? Big volcanic eruptions can cool the planet for a while because they launch tiny particles high into the sky. Those particles reflect some sunlight back to space, like a planetary s https://socialmedia.xdme.com/tony/videos-book7/page-099.mp4 https://www.youtube.com/embed/Ud1N_nXAS38 126 2026-10-02T13:45:22+00:00 yes https://xdme.com/watch-book7-q100.html https://xdme.com/book7-thumbs/page-100.jpg Why Does Caring for Earth Help Weather and Climate? Caring for Earth helps weather and climate because healthy air, water, and nature support a steady, safer world. Trees cool the air, wetlands soak up floods, and clean energy and l https://socialmedia.xdme.com/tony/videos-book7/page-100.mp4 https://www.youtube.com/embed/tb4jM8PwEjM 123 2026-10-02T13:47:54+00:00 yes https://xdme.com/watch-book7-q101.html https://xdme.com/book7-thumbs/page-101.jpg Why Is the Daytime Sky Blue? The daytime sky is blue because air scatters blue light more than other colors. Sunlight looks white, but it is really a mix of all the rainbow colors. Blue light gets bounced arou https://socialmedia.xdme.com/tony/videos-book7/page-101.mp4 https://www.youtube.com/embed/ZC-FVfH0o8E 121 2026-10-02T14:14:31+00:00 yes https://xdme.com/watch-book7-q102.html https://xdme.com/book7-thumbs/page-102.jpg Why Do Sunsets Glow Orange and Pink? Sunsets glow orange and pink because the Sun's light has to travel through much more air to reach you. Along that long path, most of the blue light is scattered away. That leaves t https://socialmedia.xdme.com/tony/videos-book7/page-102.mp4 https://www.youtube.com/embed/q4BWL3cAaF4 116 2026-10-02T14:17:02+00:00 yes https://xdme.com/watch-book7-q103.html https://xdme.com/book7-thumbs/page-103.jpg Why Does the Sky Look Redder After Wildfires or Dust? The sky looks redder after wildfires or dust storms because extra tiny particles in the air change the light. Smoke and dust scatter and filter sunlight, taking out blues and green https://socialmedia.xdme.com/tony/videos-book7/page-103.mp4 https://www.youtube.com/embed/IZmJQI9SRyQ 125 2026-10-02T14:39:09+00:00 yes https://xdme.com/watch-book7-q104.html https://xdme.com/book7-thumbs/page-104.jpg Why Do Rainbows Need Both Sun and Rain? Rainbows need both sun and rain because sunlight has to pass through raindrops to make colors. Each raindrop bends and reflects light, and splits it into colors. No rain, no classi https://socialmedia.xdme.com/tony/videos-book7/page-104.mp4 https://www.youtube.com/embed/x0JVH4oKmr4 113 2026-10-02T14:41:40+00:00 yes https://xdme.com/watch-book7-q105.html https://xdme.com/book7-thumbs/page-105.jpg Why Is a Rainbow Curved? A rainbow is curved because every raindrop sends colors back to you at a specific angle. All the drops at that same angle from your eyes form a circle in the sky. From the ground, https://socialmedia.xdme.com/tony/videos-book7/page-105.mp4 https://www.youtube.com/embed/x52gZW9VVDA 118 2026-10-02T15:08:16+00:00 yes https://xdme.com/watch-book7-q106.html https://xdme.com/book7-thumbs/page-106.jpg Why Do Rainbows Show a Set Order of Colors? Rainbows show a set order of colors because each color bends by a slightly different amount. Red bends least and violet bends most, so they leave the raindrop at slightly different https://socialmedia.xdme.com/tony/videos-book7/page-106.mp4 https://www.youtube.com/embed/4mabmrM1O_M 116 2026-10-02T15:10:17+00:00 yes https://xdme.com/watch-book7-q107.html https://xdme.com/book7-thumbs/page-107.jpg Why Can You Sometimes See a Double Rainbow? You sometimes see a double rainbow because light can bounce twice inside raindrops. The second bounce makes a fainter bow outside the main one, and its colors are reversed. A bonus https://socialmedia.xdme.com/tony/videos-book7/page-107.mp4 https://www.youtube.com/embed/tvC3z40sz_E 116 2026-10-02T15:31:23+00:00 yes https://xdme.com/watch-book7-q108.html https://xdme.com/book7-thumbs/page-108.jpg Why Can’t You Walk to the End of a Rainbow? You can't walk to the end of a rainbow because a rainbow isn't a place. It depends on where you stand and where the Sun is. When you move, the rainbow seems to move with you. https://socialmedia.xdme.com/tony/videos-book7/page-108.mp4 https://www.youtube.com/embed/-ZRk4ujhLS4 116 2026-10-02T15:35:56+00:00 yes https://xdme.com/watch-book7-q109.html https://xdme.com/book7-thumbs/page-109.jpg Why Do Soap Bubbles Show Rainbow Colors? Soap bubbles show rainbow colors because their walls are incredibly thin, and light waves interact inside them. Some colors cancel out, and others get stronger, creating shimmering https://socialmedia.xdme.com/tony/videos-book7/page-109.mp4 https://www.youtube.com/embed/RnmvnpoSQyM 122 2026-10-02T16:10:00+00:00 yes https://xdme.com/watch-book7-q110.html https://xdme.com/book7-thumbs/page-110.jpg Why Do Oil Slicks Shimmer Like Tiny Rainbows? Oil slicks shimmer like tiny rainbows because a very thin layer of oil on water works like a bubble wall. Light bounces off the top and bottom of the oil film, and the waves interf https://socialmedia.xdme.com/tony/videos-book7/page-110.mp4 https://www.youtube.com/embed/WIOl2Vl3BcU 116 2026-10-02T16:10:00+00:00 yes https://xdme.com/watch-book7-q111.html https://xdme.com/book7-thumbs/page-111.jpg Why Does Moonlight Look Silvery, Not Yellow-Hot? Moonlight looks silvery because the Moon only reflects sunlight, and it reflects just a small part of it. The Moon's gray surface is dim, so by the time the light reaches your eyes https://socialmedia.xdme.com/tony/videos-book7/page-111.mp4 https://www.youtube.com/embed/GD779RSfUTc 119 2026-10-02T16:15:07+00:00 yes https://xdme.com/watch-book7-q112.html https://xdme.com/book7-thumbs/page-112.jpg Why Do Stars Twinkle? Stars twinkle because their light passes through Earth's moving, bumpy air before it reaches your eyes. The air bends starlight a little, and the bending changes quickly, which mak https://socialmedia.xdme.com/tony/videos-book7/page-112.mp4 https://www.youtube.com/embed/dj55qGaZwTY 119 2026-10-02T16:18:08+00:00 yes https://xdme.com/watch-book7-q113.html https://xdme.com/book7-thumbs/page-113.jpg Why Does the Moon Have a Halo Sometimes? The Moon has a halo sometimes because ice crystals high in the sky bend its light into a ring. These crystals are in thin, high clouds called cirrus clouds. A lunar halo is a cryst https://socialmedia.xdme.com/tony/videos-book7/page-113.mp4 https://www.youtube.com/embed/uI8_Su1aYno 113 2026-10-02T16:20:40+00:00 yes https://xdme.com/watch-book7-q114.html https://xdme.com/book7-thumbs/page-114.jpg Why Do Sundogs Appear Beside the Sun? Sundogs are bright, glowing spots that sometimes appear on both sides of the Sun. They form when sunlight shines through tiny flat ice crystals floating in thin, wispy clouds high https://socialmedia.xdme.com/tony/videos-book7/page-114.mp4 https://www.youtube.com/embed/MO_vxgcGCvY 131 2026-10-02T10:21:46+00:00 yes https://xdme.com/watch-book7-q115.html https://xdme.com/book7-thumbs/page-115.jpg Why Does the Sky Look Purple Before a Storm? Sometimes the sky turns a moody purple before wild weather arrives. Thick storm clouds and tiny bits in the air scatter and soak up sunlight in odd ways. That mixes unusual colors, https://socialmedia.xdme.com/tony/videos-book7/page-115.mp4 https://www.youtube.com/embed/wVpfemlcvSY 124 2026-10-02T10:26:19+00:00 yes https://xdme.com/watch-book7-q116.html https://xdme.com/book7-thumbs/page-116.jpg Why Do Shadows Get Long in the Evening? In the evening your shadow can stretch out like a giant, many times taller than you! A shadow forms when your body blocks sunlight. When the Sun is low in the sky, the light arrive https://socialmedia.xdme.com/tony/videos-book7/page-116.mp4 https://www.youtube.com/embed/w3bQgF8pCbg 117 2026-10-02T10:31:24+00:00 yes https://xdme.com/watch-book7-q117.html https://xdme.com/book7-thumbs/page-117.jpg Why Does Snow Look So Bright White? Fresh snow can look dazzling on a sunny day! A snowflake is a tiny ice crystal with lots of flat, shiny sides. Snow bounces back almost all the colors of sunlight, and that is why https://socialmedia.xdme.com/tony/videos-book7/page-117.mp4 https://www.youtube.com/embed/1jtiVCW9obc 120 2026-10-02T10:36:29+00:00 yes https://xdme.com/watch-book7-q118.html https://xdme.com/book7-thumbs/page-118.jpg Why Do Clouds Turn Pink at Sunrise? At sunrise, clouds can glow in soft pink, like a blush on the sky. When the Sun is low, its light has a very long trip through the air. The blues scatter away on the way, so pink a https://socialmedia.xdme.com/tony/videos-book7/page-118.mp4 https://www.youtube.com/embed/mRz_XCxIRxI 121 2026-10-02T10:40:31+00:00 yes https://xdme.com/watch-book7-q119.html https://xdme.com/book7-thumbs/page-119.jpg Why Does Twilight Linger After Sunset? After the Sun sets, the sky does not turn black right away. That soft glow is called twilight. The Sun is below the horizon, but its light still shines on the high, thin air above https://socialmedia.xdme.com/tony/videos-book7/page-119.mp4 https://www.youtube.com/embed/KPFyuQUYcc0 123 2026-10-02T10:43:34+00:00 yes https://xdme.com/watch-book7-q120.html https://xdme.com/book7-thumbs/page-120.jpg Why Do Northern Lights Paint the Night (Aurora)? Sometimes the night sky near the poles shimmers with green and pink ribbons called the aurora. Charged particles from the Sun crash into gases in the air high above Earth. The cras https://socialmedia.xdme.com/tony/videos-book7/page-120.mp4 https://www.youtube.com/embed/9t-LsA9UZ6A 124 2026-10-02T10:47:37+00:00 yes https://xdme.com/watch-book7-q121.html https://xdme.com/book7-thumbs/page-121.jpg Why Do Mirages Shimmer on Hot Roads? On a hot day, a faraway road can look wet and shiny even when it is completely dry. That trick is called a mirage. Hot air near the ground bends light from the sky, so you see a pa https://socialmedia.xdme.com/tony/videos-book7/page-121.mp4 https://www.youtube.com/embed/SipoXoFADZ0 115 2026-10-02T10:50:40+00:00 yes https://xdme.com/watch-book7-q122.html https://xdme.com/book7-thumbs/page-122.jpg Why Does Glass Make Light Bend? Look through a glass of water, and a straw can seem broken or bent! Light slows down when it travels into glass or water. That change in speed bends its path, and that is why glass https://socialmedia.xdme.com/tony/videos-book7/page-122.mp4 https://www.youtube.com/embed/hYPnlLM2kAc 124 2026-10-02T10:56:47+00:00 yes https://xdme.com/watch-book7-q123.html https://xdme.com/book7-thumbs/page-123.jpg Why Do Sunglasses Help on Bright Days? On a bright day, you squint and your eyes feel tired and glary. Good sunglasses make the light dimmer and cut down glare, and the right ones also block harmful UV rays. That is why https://socialmedia.xdme.com/tony/videos-book7/page-123.mp4 https://www.youtube.com/embed/8Eryy2LeWMs 127 2026-10-02T10:59:50+00:00 yes https://xdme.com/watch-book7-q124.html https://xdme.com/book7-thumbs/page-124.jpg Why Does a Prism Split White Light? Shine a flashlight through a prism, and a rainbow pops out of the other side! White light is secretly a team of colors. Each color bends a different amount in glass, and that is wh https://socialmedia.xdme.com/tony/videos-book7/page-124.mp4 https://www.youtube.com/embed/Ddpyhe2PcyU 121 2026-10-02T11:05:54+00:00 yes https://xdme.com/watch-book7-q125.html https://xdme.com/book7-thumbs/page-125.jpg Why Do Photographers Chase “Golden Hour”? Photographers love the time just after sunrise and just before sunset. It is called golden hour. The Sun is low, so its light is warm, soft, and gentle. https://socialmedia.xdme.com/tony/videos-book7/page-125.mp4 https://www.youtube.com/embed/R9h6jQ42DDw 126 2026-10-02T11:13:28+00:00 yes https://xdme.com/watch-book7-q126.html https://xdme.com/book7-thumbs/page-126.jpg Why Do Weather Forecasts Help Families Plan? Should you pack a raincoat, or sunscreen? A forecast helps you decide! Forecasts use clues from the sky to guess what the weather will do next. https://socialmedia.xdme.com/tony/videos-book7/page-126.mp4 https://www.youtube.com/embed/EMrlsLyBCbc 129 2026-10-02T11:18:01+00:00 yes https://xdme.com/watch-book7-q127.html https://xdme.com/book7-thumbs/page-127.jpg Why Are Forecasts Better for Tomorrow than Next Month? A forecast for tomorrow is usually very good, but a forecast for next month is mostly a guess. The atmosphere is chaotic, so tiny errors in our measurements grow bigger as time goe https://socialmedia.xdme.com/tony/videos-book7/page-127.mp4 https://www.youtube.com/embed/ApXPq2RsKVk 127 2026-10-02T11:29:37+00:00 yes https://xdme.com/watch-book7-q128.html https://xdme.com/book7-thumbs/page-128.jpg Why Do Weather Stations Sit in Open Spots? Weather stations measure the air, and they sit out in wide open spaces. Buildings, trees, and hot pavement can change the wind, rain, and temperature around them. Open spots help t https://socialmedia.xdme.com/tony/videos-book7/page-128.mp4 https://www.youtube.com/embed/GTFIzEbr5OU 131 2026-10-02T11:32:39+00:00 yes https://xdme.com/watch-book7-q129.html https://xdme.com/book7-thumbs/page-129.jpg Why Do Kids’ School Apps Send Weather Alerts? Sometimes your family's phone buzzes with a weather alert, even when the sky looks calm. An alert pings when a watch or warning affects your area. It is like a digital tap on the s https://socialmedia.xdme.com/tony/videos-book7/page-129.mp4 https://www.youtube.com/embed/yGfpwuMjAdE 124 2026-10-02T11:45:47+00:00 yes https://xdme.com/watch-book7-q130.html https://xdme.com/book7-thumbs/page-130.jpg Why Should You Respect a Severe Weather Watch? A severe weather watch means dangerous weather could happen soon, even if the sky looks fine right now. Conditions are right for storms to form. So we stay tuned and get ready, and https://socialmedia.xdme.com/tony/videos-book7/page-130.mp4 https://www.youtube.com/embed/d_Dk5z3A070 123 2026-10-02T11:48:18+00:00 yes https://xdme.com/watch-book7-q131.html https://xdme.com/book7-thumbs/page-131.jpg Why Is a Warning More Urgent than a Watch? A watch says storms could happen. A warning says danger is happening now, or is about to. That means there is no time to wait around. https://socialmedia.xdme.com/tony/videos-book7/page-131.mp4 https://www.youtube.com/embed/c-35Z6YlR7U 123 2026-10-02T11:59:54+00:00 yes https://xdme.com/watch-book7-q132.html https://xdme.com/book7-thumbs/page-132.jpg Why Do We Practice Storm Drills? Drills teach your body and brain exactly what to do before a storm arrives. Practicing makes the steps feel familiar. Then, if a real storm comes, you can move calmly without havin https://socialmedia.xdme.com/tony/videos-book7/page-132.mp4 https://www.youtube.com/embed/wfu_EBn0x7M 117 2026-10-02T12:02:25+00:00 yes https://xdme.com/watch-book7-q133.html https://xdme.com/book7-thumbs/page-133.jpg Why Is a Weather Radio Still Useful? Phones are handy, but a weather radio has a special job. It listens for official weather alerts and announces them day and night. It keeps working when phones or power struggle, an https://socialmedia.xdme.com/tony/videos-book7/page-133.mp4 https://www.youtube.com/embed/_-i7WxkglXg 126 2026-10-02T12:23:32+00:00 yes https://xdme.com/watch-book7-q134.html https://xdme.com/book7-thumbs/page-134.jpg Why Pack a Small Go-Bag Before Storm Season? A go-bag is a small bag, packed ahead of time, with things your family might need in a storm. If you ever have to shelter or leave with grown-ups, you will not need to scramble aro https://socialmedia.xdme.com/tony/videos-book7/page-134.mp4 https://www.youtube.com/embed/kooblsWviVs 119 2026-10-02T12:26:03+00:00 yes https://xdme.com/watch-book7-q135.html https://xdme.com/book7-thumbs/page-135.jpg Why Stay Away From Windows in a Big Storm? In a big storm, one of the safest rules is to stay away from windows. Strong wind can throw branches and other objects through glass. Glass can break and cause injuries, so an insi https://socialmedia.xdme.com/tony/videos-book7/page-135.mp4 https://www.youtube.com/embed/MpQKiBjW2Zg 119 2026-10-02T13:09:41+00:00 yes https://xdme.com/watch-book7-q136.html https://xdme.com/book7-thumbs/page-136.jpg Why Unplug Gadgets Before Lightning Arrives? Lightning is incredibly powerful, and it can zap electronics even if it does not hit your house directly. A lightning surge can race through wires and fry gadgets. Before a storm, https://socialmedia.xdme.com/tony/videos-book7/page-136.mp4 https://www.youtube.com/embed/OVIo8_4DEOo 132 2026-10-02T13:11:43+00:00 yes https://xdme.com/watch-book7-q137.html https://xdme.com/book7-thumbs/page-137.jpg Why Wear Layers on Changeable Spring Days? Spring can start out chilly, turn warm by lunch, and get windy or rainy in the afternoon! Layers of clothes trap warm air, and you can add or remove them as the weather changes. Th https://socialmedia.xdme.com/tony/videos-book7/page-137.mp4 https://www.youtube.com/embed/jyVhVVwu5ro 119 2026-10-02T13:36:50+00:00 yes https://xdme.com/watch-book7-q138.html https://xdme.com/book7-thumbs/page-138.jpg Why Drink Water on Hot, Humid Days? On a hot, sticky day, your body works extra hard to stay cool. It sweats, and that sweat is mostly water that leaves your body. Drinking water replaces what you lose and helps you https://socialmedia.xdme.com/tony/videos-book7/page-138.mp4 https://www.youtube.com/embed/asTtMAuzobI 117 2026-10-02T13:39:21+00:00 yes https://xdme.com/watch-book7-q139.html https://xdme.com/book7-thumbs/page-139.jpg Why Never Play in Drainage Ditches After Rain? A ditch after a rainstorm might look like a fun place to splash. It is not safe! Ditches collect lots of rain very quickly, and the water can move fast, with hidden currents undern https://socialmedia.xdme.com/tony/videos-book7/page-139.mp4 https://www.youtube.com/embed/QTqXxyoAfj8 126 2026-10-02T14:05:29+00:00 yes https://xdme.com/watch-book7-q140.html https://xdme.com/book7-thumbs/page-140.jpg Why Check the Sky Before a Picnic or Hike? A picnic or hike is much more fun when you are not caught in a storm. Storm clouds can build fast, and you might be far from shelter. A quick look at the sky and the forecast can w https://socialmedia.xdme.com/tony/videos-book7/page-140.mp4 https://www.youtube.com/embed/BPK-_bnqYoA 124 2026-10-02T14:08:00+00:00 yes https://xdme.com/watch-book7-q141.html https://xdme.com/book7-thumbs/page-141.jpg Why Do Farmers Watch the Weather So Closely? Farmers spend their days outdoors, and the weather is like their daily boss. Rain, frost, heat, and wind decide when to plant, water, and harvest, and how to care for animals. A su https://socialmedia.xdme.com/tony/videos-book7/page-141.mp4 https://www.youtube.com/embed/EGSVglfaFcc 122 2026-10-02T14:34:36+00:00 yes https://xdme.com/watch-book7-q142.html https://xdme.com/book7-thumbs/page-142.jpg Why Do Pilots and Sailors Need Forecasts? Airplanes and ships travel for hours across big open spaces, and weather changes along the way. Pilots and sailors need to know about wind, waves, clouds, and storms before they le https://socialmedia.xdme.com/tony/videos-book7/page-142.mp4 https://www.youtube.com/embed/r_yT7O-bE6k 122 2026-10-02T14:37:08+00:00 yes https://xdme.com/watch-book7-q143.html https://xdme.com/book7-thumbs/page-143.jpg Why Can Citizen Scientists Help Weather Research? You do not need a lab coat to help real scientists. Volunteers report rain, snow depth, and sky conditions from their own backyards. Those many small reports give scientists lots o https://socialmedia.xdme.com/tony/videos-book7/page-143.mp4 https://www.youtube.com/embed/LriDARwjTck 130 2026-10-02T15:03:44+00:00 yes https://xdme.com/watch-book7-q144.html https://xdme.com/book7-thumbs/page-144.jpg Why Keep a Simple Weather Journal? A weather journal is a notebook where you write down what the sky is doing each day. Writing trains your eyes to notice details like temperature, clouds, and wind. Patterns show up https://socialmedia.xdme.com/tony/videos-book7/page-144.mp4 https://www.youtube.com/embed/-h6kHRgVDE0 118 2026-10-02T15:06:15+00:00 yes https://xdme.com/watch-book7-q145.html https://xdme.com/book7-thumbs/page-145.jpg Why Learn Local Emergency Signals? Many towns have special ways to warn people about danger, like sirens, text alerts, and radio or TV messages. Each signal has a meaning, and the meanings can differ from place to p https://socialmedia.xdme.com/tony/videos-book7/page-145.mp4 https://www.youtube.com/embed/xHUEldlCk9o 130 2026-10-02T15:28:53+00:00 yes https://xdme.com/watch-book7-q146.html https://xdme.com/book7-thumbs/page-146.jpg Why Help Neighbors After a Storm (with Grown-Ups)? After a storm passes, people nearby might have a hard time. Some neighbors need a check-in, some need help with small clean-up, and some need to charge a phone. Kind, careful help https://socialmedia.xdme.com/tony/videos-book7/page-146.mp4 https://www.youtube.com/embed/_5StDonOTac 126 2026-10-02T15:31:54+00:00 yes https://xdme.com/watch-book7-q147.html https://xdme.com/book7-thumbs/page-147.jpg Why Clean Gutters and Secure Trampolines Before Wind? Before a windy, rainy storm, grown-ups often clear gutters and tie down trampolines. Blocked gutters can overflow, and loose objects can be flung by the wind. Doing it ahead of tim https://socialmedia.xdme.com/tony/videos-book7/page-147.mp4 https://www.youtube.com/embed/Y3J7era_AzE 124 2026-10-02T16:10:03+00:00 yes https://xdme.com/watch-book7-q148.html https://xdme.com/book7-thumbs/page-148.jpg Why Is Sunscreen Still Useful on Cloudy Days? A gray, cloudy day can fool you into thinking you cannot get sunburned. Clouds block some light, but a lot of the invisible UV rays can still get through. Sunscreen still protects https://socialmedia.xdme.com/tony/videos-book7/page-148.mp4 https://www.youtube.com/embed/LS7ww-5gTbA 128 2026-10-02T16:10:04+00:00 yes https://xdme.com/watch-book7-q149.html https://xdme.com/book7-thumbs/page-149.jpg Why Talk About Feelings After Scary Storms? Loud thunder and howling wind can leave kids with big feelings, and that is completely normal. Your brain remembers scary moments, and talking helps it sort them out. Sharing your https://socialmedia.xdme.com/tony/videos-book7/page-149.mp4 https://www.youtube.com/embed/ny1jL-Ijau4 122 2026-10-02T16:18:09+00:00 yes https://xdme.com/watch-book7-q150.html https://xdme.com/book7-thumbs/page-150.jpg Why Does Asking “Why?” Make You a Weather Detective? Every time you ask why, you become a detective hunting for clues in the sky. Asking why makes you notice details, test ideas, and stay careful. It builds sharp observation, safety https://socialmedia.xdme.com/tony/videos-book7/page-150.mp4 https://www.youtube.com/embed/NxcnK7oiwFI 130 2026-10-02T16:21:11+00:00 yes https://xdme.com/watch-book8-q001.html https://xdme.com/book8-thumbs/page-001.jpg Why Can You See Only a Few Thousand Stars with Just Your Eyes? You see only a few thousand stars because most stars are too faint or too far away for your eyes alone! On a very dark, clear night, you can spot roughly 2,500 stars at once. Our g https://socialmedia.xdme.com/tony/videos-book8/page-001.mp4 https://www.youtube.com/embed/DgQslgSqefM 125 2026-10-04T02:12:59+00:00 yes https://xdme.com/watch-book8-q002.html https://xdme.com/book8-thumbs/page-002.jpg Why Are Some Stars Brighter than Others? Some stars look brighter for two reasons: how powerful they really are, and how close they are! A giant star can shine like a floodlight, while a small star nearby can look bright https://socialmedia.xdme.com/tony/videos-book8/page-002.mp4 https://www.youtube.com/embed/YnkUncSLwDE 122 2026-10-02T17:30:14+00:00 yes https://xdme.com/watch-book8-q003.html https://xdme.com/book8-thumbs/page-003.jpg Why Is the Night Sky Dark If There Are So Many Stars? The night sky is dark even with so many stars because the universe has a limited age, so light from the farthest stars has not reached us yet. The universe is also expanding, which https://socialmedia.xdme.com/tony/videos-book8/page-003.mp4 https://www.youtube.com/embed/V6FZnP-hyio 120 2026-10-04T02:13:00+00:00 yes https://xdme.com/watch-book8-q004.html https://xdme.com/book8-thumbs/page-004.jpg Why Do So Many Star Names, Like Altair and Aldebaran, Start with “Al-”? Many star names start with Al because long ago, Arab astronomers named them! In Arabic, the word al means the. So Altair means the flyer, and Aldebaran means the follower. https://socialmedia.xdme.com/tony/videos-book8/page-004.mp4 https://www.youtube.com/embed/MDordVJrr3A 125 2026-10-04T02:13:00+00:00 yes https://xdme.com/watch-book8-q005.html https://xdme.com/book8-thumbs/page-005.jpg Why Do Astronomers Agree on 88 Official Constellations? Astronomers agree on 88 constellations so everyone can talk about the same part of the sky! People long ago drew star pictures, but different places drew different ones. In 1922, a https://socialmedia.xdme.com/tony/videos-book8/page-005.mp4 https://www.youtube.com/embed/larUwuIJcq8 128 2026-10-04T02:13:01+00:00 yes https://xdme.com/watch-book8-q006.html https://xdme.com/book8-thumbs/page-006.jpg Why Do the Moon and Planets Follow the Same Path Across the Sky? The Moon and planets follow the same path because they all travel in a flat plane around the Sun! The planets orbit the Sun in a flat, pancake-shaped sheet. From Earth, that sheet https://socialmedia.xdme.com/tony/videos-book8/page-006.mp4 https://www.youtube.com/embed/Oi0Hu4GcfCI 122 2026-10-04T02:13:02+00:00 yes https://xdme.com/watch-book8-q007.html https://xdme.com/book8-thumbs/page-007.jpg Why Can’t You See Stars During the Day? We can't see stars in the day because the Sun makes the sky too bright! Sunlight bounces around in our air and fills the sky with bright blue light. That glare hides the faint star https://socialmedia.xdme.com/tony/videos-book8/page-007.mp4 https://www.youtube.com/embed/zPp1M4up2js 109 2026-10-02T17:10:00+00:00 yes https://xdme.com/watch-book8-q008.html https://xdme.com/book8-thumbs/page-008.jpg Why Can You See Different Constellations in Winter than in Summer? You see different constellations in winter and summer because Earth travels around the Sun! As the months pass, Earth moves along its orbit, so at night we face a different part of https://socialmedia.xdme.com/tony/videos-book8/page-008.mp4 https://www.youtube.com/embed/-CpwUm0PqiI 124 2026-10-04T02:13:02+00:00 yes https://xdme.com/watch-book8-q009.html https://xdme.com/book8-thumbs/page-009.jpg Why Is the Milky Way a Pale Band? The Milky Way is a pale band because we live inside a giant flat galaxy of stars! When you look along the galaxy's flat edge, millions of far away suns blend into a soft, milky riv https://socialmedia.xdme.com/tony/videos-book8/page-009.mp4 https://www.youtube.com/embed/_uqAOVuSRMU 118 2026-10-02T17:44:26+00:00 yes https://xdme.com/watch-book8-q010.html https://xdme.com/book8-thumbs/page-010.jpg Why Do City Lights Hide the Stars? City lights hide the stars because they make the night sky glow! Streetlights and signs bounce light into the air, and that skyglow washes out faint stars, like a bright room makes https://socialmedia.xdme.com/tony/videos-book8/page-010.mp4 https://www.youtube.com/embed/8YLuNRslDFw 112 2026-10-02T17:46:57+00:00 yes https://xdme.com/watch-book8-q011.html https://xdme.com/book8-thumbs/page-011.jpg Why Do Different Cultures See Different Pictures in the Same Stars? Different cultures see different pictures because stars are just dots, and imagination connects them! People everywhere noticed the same bright patterns and made up stories to reme https://socialmedia.xdme.com/tony/videos-book8/page-011.mp4 https://www.youtube.com/embed/d9PlNeSXSng 122 2026-10-04T02:13:03+00:00 yes https://xdme.com/watch-book8-q012.html https://xdme.com/book8-thumbs/page-012.jpg Why Do Stars Have Different Colors? Stars have different colors because they have different temperatures! Hotter stars glow blue-white. Cooler stars glow orange or red. https://socialmedia.xdme.com/tony/videos-book8/page-012.mp4 https://www.youtube.com/embed/YojZKE3n8TY 117 2026-10-02T17:52:31+00:00 yes https://xdme.com/watch-book8-q013.html https://xdme.com/book8-thumbs/page-013.jpg Why Do We Say Starlight Is Old Light? Starlight is old light because light takes time to travel! The rays from distant stars left years, or even centuries, ago, so tonight's sparkle is a postcard from the past. Looking https://socialmedia.xdme.com/tony/videos-book8/page-013.mp4 https://www.youtube.com/embed/zuawB38yAiQ 111 2026-10-02T17:55:33+00:00 yes https://xdme.com/watch-book8-q014.html https://xdme.com/book8-thumbs/page-014.jpg Why Do Some ‘Stars’ Move Across the Sky in Minutes? Some moving 'stars' are really satellites or the International Space Station reflecting sunlight! Real stars stay put in their patterns while Earth turns slowly. Fast movers are us https://socialmedia.xdme.com/tony/videos-book8/page-014.mp4 https://www.youtube.com/embed/L1BLknWs2Qg 119 2026-10-02T17:58:04+00:00 yes https://xdme.com/watch-book8-q015.html https://xdme.com/book8-thumbs/page-015.jpg Why Does the Big Dipper Help Find the North Star? The Big Dipper helps because two of its stars point straight to the North Star! Follow the line they make, about five times the gap between them, and you land near Polaris. Pointer https://socialmedia.xdme.com/tony/videos-book8/page-015.mp4 https://www.youtube.com/embed/MgwvtSp7OfM 106 2026-10-02T18:00:36+00:00 yes https://xdme.com/watch-book8-q016.html https://xdme.com/book8-thumbs/page-016.jpg Why Does the North Star Barely Seem to Move? The North Star barely moves because Earth's spin axis points almost right at it! Other stars seem to wheel around it all night, while Polaris sits almost still. It's the hub of the https://socialmedia.xdme.com/tony/videos-book8/page-016.mp4 https://www.youtube.com/embed/QoX3FbEiloc 115 2026-10-02T18:03:38+00:00 yes https://xdme.com/watch-book8-q017.html https://xdme.com/book8-thumbs/page-017.jpg Why Do Southern Skies Show Different Stars? Southern skies show different stars because people in the south look toward a different half of space! Their 'up' points at southern constellations that northerners rarely see. You https://socialmedia.xdme.com/tony/videos-book8/page-017.mp4 https://www.youtube.com/embed/1RRmTptye10 112 2026-10-02T18:06:40+00:00 yes https://xdme.com/watch-book8-q018.html https://xdme.com/book8-thumbs/page-018.jpg Why Do Star Clusters Look Like Glitter Piles? Star clusters look like glitter piles because hundreds or even thousands of stars can be born together from one giant cloud! Gravity keeps many of them together as a sparkling fami https://socialmedia.xdme.com/tony/videos-book8/page-018.mp4 https://www.youtube.com/embed/UlPfHxb3C-A 117 2026-10-02T18:09:41+00:00 yes https://xdme.com/watch-book8-q019.html https://xdme.com/book8-thumbs/page-019.jpg Why Do Nebulae Look Like Colorful Clouds? Nebulae look like colorful clouds because they really are giant clouds of gas and dust in space! Hot stars light them up, or dark dust lanes make shadowy shapes, painting pinks, bl https://socialmedia.xdme.com/tony/videos-book8/page-019.mp4 https://www.youtube.com/embed/f8PY8gOONak 118 2026-10-02T18:12:13+00:00 yes https://xdme.com/watch-book8-q020.html https://xdme.com/book8-thumbs/page-020.jpg Why Will Some Stars Someday Become Supernovas? Some stars become supernovas because they are very massive and burn through their fuel fast. Then they collapse and explode in a giant blast that spreads new elements into space fo https://socialmedia.xdme.com/tony/videos-book8/page-020.mp4 https://www.youtube.com/embed/DR4SWbZYXfQ 118 2026-10-02T18:15:15+00:00 yes https://xdme.com/watch-book8-q021.html https://xdme.com/book8-thumbs/page-021.jpg Why Do Binary Stars Orbit Each Other? Binary stars orbit each other because many stars are born as pairs! Their gravity locks them in a dance, so they circle a shared balance point like cosmic dance partners. Two suns https://socialmedia.xdme.com/tony/videos-book8/page-021.mp4 https://www.youtube.com/embed/AsvrnWp1Mkg 112 2026-10-02T18:17:47+00:00 yes https://xdme.com/watch-book8-q022.html https://xdme.com/book8-thumbs/page-022.jpg Why Are Black Holes Hard to See, and How Do We Find Them? Black holes are hard to see because no light can escape from them! A black hole is a place where gravity is so strong that even light can't get out. So astronomers hunt for clues a https://socialmedia.xdme.com/tony/videos-book8/page-022.mp4 https://www.youtube.com/embed/CqIUuuAslAY 126 2026-10-04T02:13:04+00:00 yes https://xdme.com/watch-book8-q023.html https://xdme.com/book8-thumbs/page-023.jpg Why Do Galaxies Look Like Spirals, Ovals, or Blobs? Galaxies have different shapes because gravity, spin, and collisions shape them over billions of years! Spirals have arms full of young stars, while ellipticals look smoother and r https://socialmedia.xdme.com/tony/videos-book8/page-023.mp4 https://www.youtube.com/embed/qLkwCKjTf_k 122 2026-10-02T18:23:52+00:00 yes https://xdme.com/watch-book8-q024.html https://xdme.com/book8-thumbs/page-024.jpg Why Does a Nearby Star Seem to Jump When Earth Moves? A nearby star seems to jump because you are looking at it from two different places! As Earth circles the Sun, a nearby star seems to shift against faraway stars. This is called pa https://socialmedia.xdme.com/tony/videos-book8/page-024.mp4 https://www.youtube.com/embed/ao6AGPmB8jg 124 2026-10-04T02:13:04+00:00 yes https://xdme.com/watch-book8-q025.html https://xdme.com/book8-thumbs/page-025.jpg Why Do People Still Stare at Stars with Just Their Eyes? People still stare at stars with just their eyes because it trains attention, and it connects us to the same sky that ancient navigators used! Telescopes help, but wonder starts wi https://socialmedia.xdme.com/tony/videos-book8/page-025.mp4 https://www.youtube.com/embed/vfChDIC6tWM 116 2026-10-02T18:29:26+00:00 yes https://xdme.com/watch-book8-q026.html https://xdme.com/book8-thumbs/page-026.jpg Why Does the Moon Look Upside Down in Australia? The Moon looks upside down in Australia because Earth is a ball! Australia is in the Southern Hemisphere, so people there stand tilted the other way compared with the north. When t https://socialmedia.xdme.com/tony/videos-book8/page-026.mp4 https://www.youtube.com/embed/F3uZBDI7an0 117 2026-10-04T02:13:05+00:00 yes https://xdme.com/watch-book8-q027.html https://xdme.com/book8-thumbs/page-027.jpg Why Is There a New Moon You Can’t See? At new Moon, the Moon is hidden by geometry! The Moon sits roughly between Earth and the Sun, so its lit side faces away from us, and the dark side faces Earth. That makes it nearl https://socialmedia.xdme.com/tony/videos-book8/page-027.mp4 https://www.youtube.com/embed/UXX5rw0k7Qg 108 2026-10-02T18:35:30+00:00 yes https://xdme.com/watch-book8-q028.html https://xdme.com/book8-thumbs/page-028.jpg Why Does a Full Moon Look So Round and Bright? A full Moon looks round and bright because we see its whole sunlit face! Earth sits roughly between the Sun and the Moon, so the Moon glows like a silver coin. Full means the entir https://socialmedia.xdme.com/tony/videos-book8/page-028.mp4 https://www.youtube.com/embed/p1cu-glbUXY 108 2026-10-02T18:38:32+00:00 yes https://xdme.com/watch-book8-q029.html https://xdme.com/book8-thumbs/page-029.jpg Why Does the Moon Seem to Follow Your Car? The Moon seems to follow your car because it is incredibly far away! The Moon is about 384,000 kilometers from Earth. A few kilometers of driving barely change where it appears in https://socialmedia.xdme.com/tony/videos-book8/page-029.mp4 https://www.youtube.com/embed/rUaDdFCMQY8 118 2026-10-04T02:13:06+00:00 yes https://xdme.com/watch-book8-q030.html https://xdme.com/book8-thumbs/page-030.jpg Why Does the Moon Rise and Set? The Moon rises and sets because Earth rotates! As our planet turns, the Moon seems to climb up, drift across the sky, and sink down, just like the Sun, but on its own schedule. Moo https://socialmedia.xdme.com/tony/videos-book8/page-030.mp4 https://www.youtube.com/embed/LcrB1vJx42U 110 2026-10-02T18:44:05+00:00 yes https://xdme.com/watch-book8-q031.html https://xdme.com/book8-thumbs/page-031.jpg Why Does Moonrise Time Change Each Day? Moonrise gets later each day because the Moon orbits Earth, sliding eastward among the stars! That extra travel means it rises about 30 to 60 minutes later each day. The Moon is th https://socialmedia.xdme.com/tony/videos-book8/page-031.mp4 https://www.youtube.com/embed/x4dCrcHciCU 112 2026-10-02T18:46:37+00:00 yes https://xdme.com/watch-book8-q032.html https://xdme.com/book8-thumbs/page-032.jpg Why Are There Two High Tides a Day, Not One? Most coasts get two high tides a day because the Moon stretches the ocean into two bulges! The Moon pulls hardest on the nearest ocean, less on Earth, and least on the far ocean. T https://socialmedia.xdme.com/tony/videos-book8/page-032.mp4 https://www.youtube.com/embed/9kEC6t9nRmY 116 2026-10-04T02:13:06+00:00 yes https://xdme.com/watch-book8-q033.html https://xdme.com/book8-thumbs/page-033.jpg Why Are Some Tides Especially High (Spring Tides)? Spring tides are especially high because the Sun and Moon line up! At new or full Moon, their pulls add together, so the oceans bulge more. They happen all year round, not just in https://socialmedia.xdme.com/tony/videos-book8/page-033.mp4 https://www.youtube.com/embed/JVOvP6FO3VA 110 2026-10-02T18:52:11+00:00 yes https://xdme.com/watch-book8-q034.html https://xdme.com/book8-thumbs/page-034.jpg Why Do Bright Streaks Spray Out From a Few Spots on the Moon? The bright streaks on the Moon come from space rocks that crashed into it! When a space rock hits the Moon, it throws out bright, fresh material that spreads far from the crater in https://socialmedia.xdme.com/tony/videos-book8/page-034.mp4 https://www.youtube.com/embed/-SMWoemmeGU 124 2026-10-04T02:13:07+00:00 yes https://xdme.com/watch-book8-q035.html https://xdme.com/book8-thumbs/page-035.jpg Why Can You Sometimes See the Dark Part of a Crescent Moon? You can sometimes see the dark part of a crescent Moon because of Earthshine! Sunlight bounces off Earth onto the Moon's night side, gently lighting the rest of the disk like a gho https://socialmedia.xdme.com/tony/videos-book8/page-035.mp4 https://www.youtube.com/embed/ra1nbSb58gs 111 2026-10-02T18:57:17+00:00 yes https://xdme.com/watch-book8-q036.html https://xdme.com/book8-thumbs/page-036.jpg Why Do Lunar Eclipses Turn the Moon Reddish? A lunar eclipse turns the Moon reddish because Earth blocks direct sunlight! But bent rays through our air, especially the red ones, still reach the Moon and paint it copper. Eclip https://socialmedia.xdme.com/tony/videos-book8/page-036.mp4 https://www.youtube.com/embed/hWxHVFT1_oo 113 2026-10-02T19:00:18+00:00 yes https://xdme.com/watch-book8-q037.html https://xdme.com/book8-thumbs/page-037.jpg Why Are Solar Eclipses Rarer to See From Your Town? Total solar eclipses are rare in any one town because the Moon's shadow on Earth is a small, moving bull's-eye! Only people inside that narrow path see a total eclipse. Most places https://socialmedia.xdme.com/tony/videos-book8/page-037.mp4 https://www.youtube.com/embed/q6DN-PN_xk4 121 2026-10-02T19:02:51+00:00 yes https://xdme.com/watch-book8-q038.html https://xdme.com/book8-thumbs/page-038.jpg Why Does the Moon Have Craters? The Moon has craters because asteroids and comets smashed into it for billions of years! With almost no air or weather to erase the scars, craters stay as cosmic footprints. The Mo https://socialmedia.xdme.com/tony/videos-book8/page-038.mp4 https://www.youtube.com/embed/qmJ0Y0j5pMQ 117 2026-10-02T19:05:52+00:00 yes https://xdme.com/watch-book8-q039.html https://xdme.com/book8-thumbs/page-039.jpg Why Are There Dark Patches on the Moon? The dark patches on the Moon are ancient lava plains! Long ago, lava flooded huge basins and cooled into smooth plains called maria, which means seas. They are darker rock, not rea https://socialmedia.xdme.com/tony/videos-book8/page-039.mp4 https://www.youtube.com/embed/Xd3xV_IccJU 115 2026-10-02T19:08:25+00:00 yes https://xdme.com/watch-book8-q040.html https://xdme.com/book8-thumbs/page-040.jpg Why Is Moon Dust So Clingy for Astronauts? Moon dust is clingy because the grains are tiny, sharp, and jagged! There is no water or wind on the Moon to round them off, so static electricity and jagged edges make the dust st https://socialmedia.xdme.com/tony/videos-book8/page-040.mp4 https://www.youtube.com/embed/axd5oT0WEH0 114 2026-10-02T19:11:26+00:00 yes https://xdme.com/watch-book8-q041.html https://xdme.com/book8-thumbs/page-041.jpg Why Is There Almost No Weather on the Moon? There is almost no weather on the Moon because it has almost no air! The Moon's gravity is too weak to hold a thick atmosphere, so there is no wind, rain, or clouds, only silent, d https://socialmedia.xdme.com/tony/videos-book8/page-041.mp4 https://www.youtube.com/embed/nKi-3T3cPBA 111 2026-10-02T19:13:58+00:00 yes https://xdme.com/watch-book8-q042.html https://xdme.com/book8-thumbs/page-042.jpg Why Does Daylight on the Moon Last About Two Earth Weeks? A day on the Moon lasts about two Earth weeks because the Moon spins very slowly! One lunar daytime is roughly 14 Earth days of sunlight, followed by about 14 days of night. A luna https://socialmedia.xdme.com/tony/videos-book8/page-042.mp4 https://www.youtube.com/embed/RWP-fuBY-W4 116 2026-10-04T02:13:08+00:00 yes https://xdme.com/watch-book8-q043.html https://xdme.com/book8-thumbs/page-043.jpg Why Did Apollo Astronauts Bounce When They Walked? Apollo astronauts bounced because Moon gravity is about one-sixth of Earth's! The same leg push flings you higher and farther, and the hops look like slow-motion dancing. Less grav https://socialmedia.xdme.com/tony/videos-book8/page-043.mp4 https://www.youtube.com/embed/n7Gc26Mr-YY 113 2026-10-02T19:19:32+00:00 yes https://xdme.com/watch-book8-q044.html https://xdme.com/book8-thumbs/page-044.jpg Why Does the Moon Help Keep Earth’s Tilt Steadier? The Moon helps keep Earth's tilt steady! Its gravity acts like a stabilizing buddy for the way Earth leans as it spins. A steadier tilt helps our seasons stay more predictable over https://socialmedia.xdme.com/tony/videos-book8/page-044.mp4 https://www.youtube.com/embed/ert5yXxe9x0 116 2026-10-02T19:22:05+00:00 yes https://xdme.com/watch-book8-q045.html https://xdme.com/book8-thumbs/page-045.jpg Why Can the Moon Occult (Cover) a Star or Planet? The Moon can occult, or cover, a star or planet because it drifts east among the stars! As it moves, it can slide in front of a star or planet and briefly hide it, like a sky eclip https://socialmedia.xdme.com/tony/videos-book8/page-045.mp4 https://www.youtube.com/embed/SQOTR2vvHww 116 2026-10-02T19:25:07+00:00 yes https://xdme.com/watch-book8-q046.html https://xdme.com/book8-thumbs/page-046.jpg Why Do Calendars Sometimes Have a ‘Blue Moon’? A Blue Moon is not really blue! The name usually means the second full Moon in one calendar month. It is about timing, not color, and "once in a blue Moon" means something very rar https://socialmedia.xdme.com/tony/videos-book8/page-046.mp4 https://www.youtube.com/embed/yMRwDa4sFVY 106 2026-10-02T19:27:38+00:00 yes https://xdme.com/watch-book8-q047.html https://xdme.com/book8-thumbs/page-047.jpg Why Does the Moon Look Bright If Its Rock Is as Dark as Old Pavement? The Moon looks bright because it is lit by the Sun, and the night sky around it is dark! The Moon's rock reflects only about 12 percent of the sunlight that hits it, a bit like wor https://socialmedia.xdme.com/tony/videos-book8/page-047.mp4 https://www.youtube.com/embed/_1K4QhhgtAE 120 2026-10-04T02:13:08+00:00 yes https://xdme.com/watch-book8-q048.html https://xdme.com/book8-thumbs/page-048.jpg Why Is the Moon Slowly Drifting Away From Earth? The Moon is drifting away because ocean tides pass a little of Earth's spin energy to it! That nudges the Moon about 3.8 centimeters farther away each year. That is about how fast https://socialmedia.xdme.com/tony/videos-book8/page-048.mp4 https://www.youtube.com/embed/ljyIVERDDM8 118 2026-10-04T02:13:09+00:00 yes https://xdme.com/watch-book8-q049.html https://xdme.com/book8-thumbs/page-049.jpg Why Did People Once Think the Moon Made People ‘Loony’? People once thought the Moon made people loony because old myths linked full Moons to odd behavior! But science doesn't support a moonlight mind-control effect. Bright nights do ch https://socialmedia.xdme.com/tony/videos-book8/page-049.mp4 https://www.youtube.com/embed/lW-UmF10Vo4 114 2026-10-02T19:35:48+00:00 yes https://xdme.com/watch-book8-q050.html https://xdme.com/book8-thumbs/page-050.jpg Why Do Future Explorers Still Want to Return to the Moon? Future explorers want to return to the Moon because it is a nearby lab for science! It is a place to practice for deeper space, and to study water ice, rocks, and new technology. T https://socialmedia.xdme.com/tony/videos-book8/page-050.mp4 https://www.youtube.com/embed/spumf0x-0-4 121 2026-10-02T19:38:49+00:00 yes https://xdme.com/watch-book8-q051.html https://xdme.com/book8-thumbs/page-051.jpg Why Is the Sun a Star, Not a Planet? The Sun is a star because it makes its own light! Deep inside, it fuses hydrogen and releases gigantic energy. Planets don't do that. https://socialmedia.xdme.com/tony/videos-book8/page-051.mp4 https://www.youtube.com/embed/XVZJZIwJtbQ 125 2026-10-02T19:41:22+00:00 yes https://xdme.com/watch-book8-q052.html https://xdme.com/book8-thumbs/page-052.jpg Why Does the Sun's Middle Spin Faster than Its Top and Bottom? The Sun's middle spins faster because the Sun is a giant ball of hot gas, not solid rock! Different parts of a gas ball can turn at different speeds. The Sun's middle spins once in https://socialmedia.xdme.com/tony/videos-book8/page-052.mp4 https://www.youtube.com/embed/a84wk_qstAM 125 2026-10-04T02:13:10+00:00 yes https://xdme.com/watch-book8-q053.html https://xdme.com/book8-thumbs/page-053.jpg Why Must You Never Stare at the Sun? Never stare at the Sun, because sunlight can permanently damage your eyes! It's so bright and strong that it can hurt the delicate parts at the back of your eye. Even a quick look https://socialmedia.xdme.com/tony/videos-book8/page-053.mp4 https://www.youtube.com/embed/mSc5aGtb6_M 119 2026-10-02T19:46:56+00:00 yes https://xdme.com/watch-book8-q054.html https://xdme.com/book8-thumbs/page-054.jpg Why Are Planet Orbits Ovals, Not Perfect Circles? Planet orbits are ovals because of how the Sun's pull and a planet's sideways speed work together! Together they shape the path into a slightly stretched circle called an ellipse. https://socialmedia.xdme.com/tony/videos-book8/page-054.mp4 https://www.youtube.com/embed/xpp4Q_LaD54 118 2026-10-04T02:13:10+00:00 yes https://xdme.com/watch-book8-q055.html https://xdme.com/book8-thumbs/page-055.jpg Why Is Mercury So Extremely Hot and Cold? Mercury is both super hot and super cold because it's the closest planet to the Sun, and it has almost no air! Air works like a blanket, holding heat in. Mercury has none, so heat https://socialmedia.xdme.com/tony/videos-book8/page-055.mp4 https://www.youtube.com/embed/9PUg-dTz5hw 121 2026-10-04T02:13:12+00:00 yes https://xdme.com/watch-book8-q056.html https://xdme.com/book8-thumbs/page-056.jpg Why Is Venus Hotter than Mercury Even Farther Out? Venus is hotter than Mercury because it's wrapped in a very thick blanket of carbon dioxide gas! That traps heat in a runaway greenhouse effect. So distance isn't the only thermost https://socialmedia.xdme.com/tony/videos-book8/page-056.mp4 https://www.youtube.com/embed/fcn6zdY8PTw 120 2026-10-02T19:56:03+00:00 yes https://xdme.com/watch-book8-q057.html https://xdme.com/book8-thumbs/page-057.jpg Why Is Earth Called the Goldilocks Planet? Earth is called the Goldilocks planet because conditions here are just right! Not too hot, not too cold, so liquid water can stay on the surface. Liquid water is key for life as we https://socialmedia.xdme.com/tony/videos-book8/page-057.mp4 https://www.youtube.com/embed/8o47HrjcQ_U 118 2026-10-02T19:58:35+00:00 yes https://xdme.com/watch-book8-q058.html https://xdme.com/book8-thumbs/page-058.jpg Why Does the Red Planet Have Blue Sunsets? Mars has blue sunsets because its fine dust scatters light in a different way than Earth's air! Rusty iron dust makes Mars look red. But that same fine dust scatters light so the s https://socialmedia.xdme.com/tony/videos-book8/page-058.mp4 https://www.youtube.com/embed/g2b1gLiZNk8 119 2026-10-04T02:13:13+00:00 yes https://xdme.com/watch-book8-q059.html https://xdme.com/book8-thumbs/page-059.jpg Why Do Mars Rovers Need Tough Wheels and Brains? Mars rovers need tough wheels and clever brains because Mars is rocky, sandy, and cold. Plus, radio messages from Earth take a long time to arrive! So rovers must roll carefully an https://socialmedia.xdme.com/tony/videos-book8/page-059.mp4 https://www.youtube.com/embed/T7VGJBz9pA4 122 2026-10-02T20:04:09+00:00 yes https://xdme.com/watch-book8-q060.html https://xdme.com/book8-thumbs/page-060.jpg Why Is Jupiter a Gas Giant? Jupiter is a gas giant because it's made mostly of hydrogen and helium gas, with no solid ground like Earth's crust! You couldn't stand on it. As you go deeper, the gas gets thicke https://socialmedia.xdme.com/tony/videos-book8/page-060.mp4 https://www.youtube.com/embed/zsBNEoPiCl0 117 2026-10-02T20:06:41+00:00 yes https://xdme.com/watch-book8-q061.html https://xdme.com/book8-thumbs/page-061.jpg Why Does Jupiter Have a Great Red Spot? Jupiter has a Great Red Spot because it's a gigantic storm that has been spinning for hundreds of years! It's bigger than Earth itself. Jupiter spins very fast and has a thick atmo https://socialmedia.xdme.com/tony/videos-book8/page-061.mp4 https://www.youtube.com/embed/E0ihSIP0ymo 120 2026-10-02T20:09:12+00:00 yes https://xdme.com/watch-book8-q062.html https://xdme.com/book8-thumbs/page-062.jpg Why Does Titan, One of Saturn's Moons, Have Thick Orange Air? Titan has thick orange air because sunlight turns its gases into an orange haze! Titan is the only moon with a thick atmosphere, made mostly of nitrogen with a little methane. Sunl https://socialmedia.xdme.com/tony/videos-book8/page-062.mp4 https://www.youtube.com/embed/sVPsbqJDkX0 120 2026-10-04T02:13:16+00:00 yes https://xdme.com/watch-book8-q063.html https://xdme.com/book8-thumbs/page-063.jpg Why Does Neptune Have the Fastest Winds in the Solar System? Neptune has the fastest winds because its own inner heat stirs its thick atmosphere! Neptune gets very little sunlight, yet its winds blow up to about 2,000 kilometers per hour. Sc https://socialmedia.xdme.com/tony/videos-book8/page-063.mp4 https://www.youtube.com/embed/4vKT8bg5UiI 128 2026-10-04T02:13:18+00:00 yes https://xdme.com/watch-book8-q064.html https://xdme.com/book8-thumbs/page-064.jpg Why Are Uranus and Neptune Called Ice Giants? Uranus and Neptune are called ice giants because they hold lots of water, ammonia, and methane, which astronomers call ices, mixed in with gases! That's a different recipe from Jup https://socialmedia.xdme.com/tony/videos-book8/page-064.mp4 https://www.youtube.com/embed/xhXMn6CwYnM 123 2026-10-02T20:17:17+00:00 yes https://xdme.com/watch-book8-q065.html https://xdme.com/book8-thumbs/page-065.jpg Why Does Uranus Roll on Its Side? Uranus rolls on its side because its spin axis is tipped over about 98 degrees! Scientists think a giant object may have crashed into it long ago. So Uranus spins like a ball rolli https://socialmedia.xdme.com/tony/videos-book8/page-065.mp4 https://www.youtube.com/embed/wM13NeTcX-U 118 2026-10-02T20:20:19+00:00 yes https://xdme.com/watch-book8-q066.html https://xdme.com/book8-thumbs/page-066.jpg Why Is Pluto Now Called a Dwarf Planet? Pluto is called a dwarf planet because astronomers refined what the word planet means! Pluto orbits the Sun and is round, but it hasn't cleared other objects out of its path. It's https://socialmedia.xdme.com/tony/videos-book8/page-066.mp4 https://www.youtube.com/embed/uq5tY3TRwnQ 122 2026-10-02T20:22:50+00:00 yes https://xdme.com/watch-book8-q067.html https://xdme.com/book8-thumbs/page-067.jpg Why Do Some Planets Have Dozens of Moons? Some planets have dozens of moons because strong gravity can capture passing objects, and it can also keep leftover pieces from the planet's formation circling nearby. Giant planet https://socialmedia.xdme.com/tony/videos-book8/page-067.mp4 https://www.youtube.com/embed/EcSLtXSkUdE 124 2026-10-02T20:25:23+00:00 yes https://xdme.com/watch-book8-q068.html https://xdme.com/book8-thumbs/page-068.jpg Why Is the Asteroid Belt Between Mars and Jupiter? The asteroid belt sits between Mars and Jupiter because leftover rocky pieces there never grew into a full planet. Jupiter's strong gravity stirred the region and kept them apart. https://socialmedia.xdme.com/tony/videos-book8/page-068.mp4 https://www.youtube.com/embed/C8d3G-ARe68 121 2026-10-02T20:28:24+00:00 yes https://xdme.com/watch-book8-q069.html https://xdme.com/book8-thumbs/page-069.jpg Why Do Inner Planets Take Less Time to Orbit the Sun? Inner planets take less time to orbit the Sun because they have shorter paths and move faster! The Sun's gravity is stronger close to it. Mercury zips around in only 88 Earth days, https://socialmedia.xdme.com/tony/videos-book8/page-069.mp4 https://www.youtube.com/embed/Y1Cnhzlrc8c 125 2026-10-02T20:30:56+00:00 yes https://xdme.com/watch-book8-q070.html https://xdme.com/book8-thumbs/page-070.jpg Why Will the Sun Keep Shining for Billions of Years? The Sun will keep shining for billions of years because it has plenty of fuel left! The Sun is about 4.6 billion years old and has enough hydrogen fuel to shine for roughly 5 billi https://socialmedia.xdme.com/tony/videos-book8/page-070.mp4 https://www.youtube.com/embed/9Es85h72eg4 118 2026-10-04T02:13:19+00:00 yes https://xdme.com/watch-book8-q071.html https://xdme.com/book8-thumbs/page-071.jpg Why Is a Day on Venus Longer than Its Year? A day on Venus is longer than its year because Venus spins incredibly slowly! Venus takes about 243 Earth days to turn around once. But it circles the Sun in only about 225 Earth d https://socialmedia.xdme.com/tony/videos-book8/page-071.mp4 https://www.youtube.com/embed/xaWut_nKc18 121 2026-10-04T02:13:20+00:00 yes https://xdme.com/watch-book8-q072.html https://xdme.com/book8-thumbs/page-072.jpg Why Do Planets Sometimes Look Like They Go Backward? Planets sometimes look like they go backward because of a trick of perspective! When Earth catches up to and passes an outer planet, that planet seems to loop back against the star https://socialmedia.xdme.com/tony/videos-book8/page-072.mp4 https://www.youtube.com/embed/XYoM7vt7za0 116 2026-10-02T20:38:32+00:00 yes https://xdme.com/watch-book8-q073.html https://xdme.com/book8-thumbs/page-073.jpg Why Is the Sun’s Surface Speckled with Sunspots? The Sun's surface is speckled with sunspots, which are patches where magnetic knots make the surface cooler. So those patches look darker than their surroundings. Sunspot numbers r https://socialmedia.xdme.com/tony/videos-book8/page-073.mp4 https://www.youtube.com/embed/Sx6J1KVFVhs 124 2026-10-02T20:41:03+00:00 yes https://xdme.com/watch-book8-q074.html https://xdme.com/book8-thumbs/page-074.jpg Why Does Solar Wind Shape a Huge Bubble Around the Planets? The Sun blows a stream of charged particles into space called the solar wind. It pushes outward so far that it inflates a huge bubble around the planets, called the heliosphere. It https://socialmedia.xdme.com/tony/videos-book8/page-074.mp4 https://www.youtube.com/embed/kaOttpUkNdQ 114 2026-10-02T20:43:34+00:00 yes https://xdme.com/watch-book8-q075.html https://xdme.com/book8-thumbs/page-075.jpg Why Do Scientists Still Discover New Small Worlds? Scientists still discover new small worlds because telescopes and sky surveys keep getting better! Icy bodies in the outer solar system are dim and far away, so they hide until lig https://socialmedia.xdme.com/tony/videos-book8/page-075.mp4 https://www.youtube.com/embed/mtOFo9EJeWE 121 2026-10-02T20:47:06+00:00 yes https://xdme.com/watch-book8-q076.html https://xdme.com/book8-thumbs/page-076.jpg Why Do Rockets Turn and Roll Shortly After Liftoff? Rockets turn and roll after liftoff so they can head in the right direction for their orbit! Soon after liftoff, many rockets twist around their long axis in a roll program. After https://socialmedia.xdme.com/tony/videos-book8/page-076.mp4 https://www.youtube.com/embed/XBtycsjZdSs 116 2026-10-04T02:13:20+00:00 yes https://xdme.com/watch-book8-q077.html https://xdme.com/book8-thumbs/page-077.jpg Why Do Rockets Drop Stages as They Climb? Rockets drop stages as they climb because empty tanks are dead weight! Staging drops the empties, so the next engines only lift what's left. It's smarter climbing, like a backpack https://socialmedia.xdme.com/tony/videos-book8/page-077.mp4 https://www.youtube.com/embed/FFmT92g4JVY 120 2026-10-02T17:10:03+00:00 yes https://xdme.com/watch-book8-q078.html https://xdme.com/book8-thumbs/page-078.jpg Why Do Rockets Rise Slowly at First and Then Speed Up? Rockets rise slowly at first because they are very heavy when they are full of fuel! At liftoff, a rocket's engines barely beat gravity. As fuel burns away, the rocket gets lighter https://socialmedia.xdme.com/tony/videos-book8/page-078.mp4 https://www.youtube.com/embed/OaSmqS9DrSc 111 2026-10-04T02:13:21+00:00 yes https://xdme.com/watch-book8-q079.html https://xdme.com/book8-thumbs/page-079.jpg Why Do Astronauts on the Space Station See About 16 Sunrises a Day? Astronauts see about 16 sunrises a day because the space station circles Earth super fast! The station orbits Earth about every 90 minutes. So it passes from daylight into darkness https://socialmedia.xdme.com/tony/videos-book8/page-079.mp4 https://www.youtube.com/embed/R399dHvw9Pc 128 2026-10-04T02:13:22+00:00 yes https://xdme.com/watch-book8-q080.html https://xdme.com/book8-thumbs/page-080.jpg Why Do Astronauts Grow a Little Taller in Space? Astronauts grow a little taller in space because gravity stops squeezing their spines! Without gravity squeezing down, the cushions between the bones of the spine spread out. Astro https://socialmedia.xdme.com/tony/videos-book8/page-080.mp4 https://www.youtube.com/embed/oDnJTK5qvhU 116 2026-10-04T02:13:45+00:00 yes https://xdme.com/watch-book8-q081.html https://xdme.com/book8-thumbs/page-081.jpg Why Do Satellites Stay Up Without Flapping Wings? Satellites stay up without flapping wings because they move sideways so fast that, as they fall, Earth curves away beneath them! Orbit is high-speed falling in a circle. They don't https://socialmedia.xdme.com/tony/videos-book8/page-081.mp4 https://www.youtube.com/embed/K2iZ8FZ4R0s 123 2026-10-02T17:10:16+00:00 yes https://xdme.com/watch-book8-q082.html https://xdme.com/book8-thumbs/page-082.jpg Why Are Communications Satellites Often Parked High Above the Equator? Communications satellites are often parked high above the equator because in a geostationary orbit, a satellite matches Earth's spin and seems to hover over one spot! That's perfec https://socialmedia.xdme.com/tony/videos-book8/page-082.mp4 https://www.youtube.com/embed/rnn6FdMRsk8 120 2026-10-02T17:10:17+00:00 yes https://xdme.com/watch-book8-q083.html https://xdme.com/book8-thumbs/page-083.jpg Why Do GPS Satellites Need Einstein's Help? GPS satellites need Einstein's help because their clocks tick a little differently from clocks on the ground! Clocks tick slightly differently up high and at high speed, so enginee https://socialmedia.xdme.com/tony/videos-book8/page-083.mp4 https://www.youtube.com/embed/bZrfbDxYwnY 117 2026-10-04T02:13:46+00:00 yes https://xdme.com/watch-book8-q084.html https://xdme.com/book8-thumbs/page-084.jpg Why Does the International Space Station Need Constant Boosts? The International Space Station needs constant boosts because even at its height, there's a trace of thin air that creates drag. Without occasional reboosts, the station would slow https://socialmedia.xdme.com/tony/videos-book8/page-084.mp4 https://www.youtube.com/embed/M1WHBIIeWVc 120 2026-10-02T17:10:23+00:00 yes https://xdme.com/watch-book8-q085.html https://xdme.com/book8-thumbs/page-085.jpg Why Do Astronauts Exercise Every Day in Space? Astronauts exercise every day in space because without Earth's usual gravity load, bones and muscles weaken. Workouts fight that, so bodies stay stronger for the trip home. They ex https://socialmedia.xdme.com/tony/videos-book8/page-085.mp4 https://www.youtube.com/embed/5zIQ1udd_lw 119 2026-10-02T17:10:26+00:00 yes https://xdme.com/watch-book8-q086.html https://xdme.com/book8-thumbs/page-086.jpg Why Is Space Food Sticky or Packed in Pouches? Space food is sticky or packed in pouches because crumbs and floating blobs are hazards! Without gravity, nothing stays put on a plate. Sticky, wet, or pouch foods behave better in https://socialmedia.xdme.com/tony/videos-book8/page-086.mp4 https://www.youtube.com/embed/OAWmFgS4PYc 120 2026-10-02T17:10:27+00:00 yes https://xdme.com/watch-book8-q087.html https://xdme.com/book8-thumbs/page-087.jpg Why Do Launches Pause for Weather Sometimes? Launches pause for weather because lightning, strong winds, and clouds can endanger rockets and crews! Range safety teams wait for safer skies. Spaceflight still respects Earth's w https://socialmedia.xdme.com/tony/videos-book8/page-087.mp4 https://www.youtube.com/embed/UaCH_3DGiDQ 118 2026-10-02T17:10:28+00:00 yes https://xdme.com/watch-book8-q088.html https://xdme.com/book8-thumbs/page-088.jpg Why Do Heat Shields Glow on the Way Home? Heat shields glow on the way home because a returning spacecraft slams into air at orbital speed! That squeezes and heats the air into a fiery glowing plasma, and the shield takes https://socialmedia.xdme.com/tony/videos-book8/page-088.mp4 https://www.youtube.com/embed/lC-WgClrVPU 116 2026-10-02T17:10:29+00:00 yes https://xdme.com/watch-book8-q089.html https://xdme.com/book8-thumbs/page-089.jpg Why Do Space Toilets Use Air Flow, Not Water Swirls? Space toilets use airflow instead of water because there's no gravity to pull things down! Without gravity, water won't fall into a bowl. Fans pull waste away safely instead. https://socialmedia.xdme.com/tony/videos-book8/page-089.mp4 https://www.youtube.com/embed/q_WsgmMdP-E 121 2026-10-02T17:10:31+00:00 yes https://xdme.com/watch-book8-q090.html https://xdme.com/book8-thumbs/page-090.jpg Why Do Astronauts Sleep in Sleeping Bags Clipped to Walls? Astronauts sleep in sleeping bags clipped to walls because you can't really lie down without gravity! The bags keep sleepers from drifting into instruments in the middle of a dream https://socialmedia.xdme.com/tony/videos-book8/page-090.mp4 https://www.youtube.com/embed/OYmPx8Ms2ko 114 2026-10-02T17:10:34+00:00 yes https://xdme.com/watch-book8-q091.html https://xdme.com/book8-thumbs/page-091.jpg Why Are Clean Rooms Used Before Launch? Clean rooms are used before launch because dust and tiny germs can ruin delicate instruments or contaminate science samples! Ultra-clean assembly keeps spacecraft healthy. Even a s https://socialmedia.xdme.com/tony/videos-book8/page-091.mp4 https://www.youtube.com/embed/MDRxfJJnzu0 113 2026-10-02T17:12:35+00:00 yes https://xdme.com/watch-book8-q092.html https://xdme.com/book8-thumbs/page-092.jpg Why Do Mission Control Teams Work in Shifts? Mission control teams work in shifts because spaceflight runs 24 hours a day, 7 days a week! Teams hand off to each other so someone is always watching the systems, the science, an https://socialmedia.xdme.com/tony/videos-book8/page-092.mp4 https://www.youtube.com/embed/qIbwKxVboU0 122 2026-10-02T17:15:07+00:00 yes https://xdme.com/watch-book8-q093.html https://xdme.com/book8-thumbs/page-093.jpg Why Do Spacewalkers Tether Themselves? Spacewalkers tether themselves because there is no air to slow you down and no ground to stop you, so a gentle push could send you floating away from the station. Tethers and handh https://socialmedia.xdme.com/tony/videos-book8/page-093.mp4 https://www.youtube.com/embed/XCOQTrRzXmc 119 2026-10-02T17:18:09+00:00 yes https://xdme.com/watch-book8-q094.html https://xdme.com/book8-thumbs/page-094.jpg Why Do Rockets Launch Toward the East Often? Rockets often launch toward the east because Earth already spins eastward! Launching east borrows that free speed, saving fuel on the way to orbit. At the equator, the ground itsel https://socialmedia.xdme.com/tony/videos-book8/page-094.mp4 https://www.youtube.com/embed/LaHWbJWBEvQ 119 2026-10-02T17:20:40+00:00 yes https://xdme.com/watch-book8-q095.html https://xdme.com/book8-thumbs/page-095.jpg Why Are Reusable Rockets a Big Deal? Reusable rockets are a big deal because landing and flying boosters again cuts cost and waste! More flights mean more science and more chances to explore. Before, rockets were thro https://socialmedia.xdme.com/tony/videos-book8/page-095.mp4 https://www.youtube.com/embed/0MdXemSfXmU 120 2026-10-02T17:23:41+00:00 yes https://xdme.com/watch-book8-q096.html https://xdme.com/book8-thumbs/page-096.jpg Why Do Cubesats Hitch Rides to Space? Cubesats hitch rides to space because they're tiny, standardized satellites that can share rocket room! Students and companies can afford small experiments on big launches. A basic https://socialmedia.xdme.com/tony/videos-book8/page-096.mp4 https://www.youtube.com/embed/qPqsy45UnEI 120 2026-10-02T17:26:12+00:00 yes https://xdme.com/watch-book8-q097.html https://xdme.com/book8-thumbs/page-097.jpg Why Is Radio Delay a Problem Toward Mars? Radio delay is a problem toward Mars because even light-speed signals take minutes each way! Conversations turn into slow voicemail. So probes and rovers need onboard smarts to mak https://socialmedia.xdme.com/tony/videos-book8/page-097.mp4 https://www.youtube.com/embed/J4gzUNxfrcw 118 2026-10-02T17:30:15+00:00 yes https://xdme.com/watch-book8-q098.html https://xdme.com/book8-thumbs/page-098.jpg Why Do Astronauts Train Underwater? Astronauts train underwater because neutral buoyancy pools mimic floating! Suits and tools behave somewhat like they do on a spacewalk, without leaving Earth. In the pool, the wate https://socialmedia.xdme.com/tony/videos-book8/page-098.mp4 https://www.youtube.com/embed/hFm_eEpyKjs 122 2026-10-02T17:33:48+00:00 yes https://xdme.com/watch-book8-q099.html https://xdme.com/book8-thumbs/page-099.jpg Why Do Spacecraft Need Many Computers and Backups? Spacecraft need many computers and backups because radiation and failures happen! Redundant systems keep missions alive when one computer hiccups. If one computer fails, another ca https://socialmedia.xdme.com/tony/videos-book8/page-099.mp4 https://www.youtube.com/embed/H3-w_jvPpgI 128 2026-10-02T17:39:22+00:00 yes https://xdme.com/watch-book8-q100.html https://xdme.com/book8-thumbs/page-100.jpg Why Would a Trip to Mars Take Months? A trip to Mars would take months because Mars is very, very far away! A trip takes about seven months each way, and crews might wait over a year for the planets to line up for home https://socialmedia.xdme.com/tony/videos-book8/page-100.mp4 https://www.youtube.com/embed/QtkDG0wF5Xo 121 2026-10-04T02:13:46+00:00 yes https://xdme.com/watch-book8-q101.html https://xdme.com/book8-thumbs/page-101.jpg Why Do Some Meteors Blaze Into Fireballs? Some meteors blaze into fireballs because the space rock is bigger than most! Pea-sized and bigger rocks heat the air so strongly that they flare brighter than planets. Sometimes y https://socialmedia.xdme.com/tony/videos-book8/page-101.mp4 https://www.youtube.com/embed/7329Ovg8rSc 112 2026-10-04T02:13:47+00:00 yes https://xdme.com/watch-book8-q102.html https://xdme.com/book8-thumbs/page-102.jpg Why Are Meteor Showers Named After Constellations? Meteor showers are named after constellations because their streaks seem to come from that part of the sky! If you trace the streaks backward, they all appear to start from one spo https://socialmedia.xdme.com/tony/videos-book8/page-102.mp4 https://www.youtube.com/embed/64iwe1KPNgY 113 2026-10-02T17:50:00+00:00 yes https://xdme.com/watch-book8-q103.html https://xdme.com/book8-thumbs/page-103.jpg Why Do Some Meteorites Make Craters on Earth? Some meteorites make craters because bigger, tougher space rocks survive the dive and crash into the ground with huge energy! Most space rocks burn up in the air. But a large stron https://socialmedia.xdme.com/tony/videos-book8/page-103.mp4 https://www.youtube.com/embed/twZagxuJCzg 115 2026-10-02T17:53:02+00:00 yes https://xdme.com/watch-book8-q104.html https://xdme.com/book8-thumbs/page-104.jpg Why Do Some Comets Glow Green? Some comets glow green because sunlight makes a special gas around the comet's head glow! Sunlight makes gases around a comet's head glow, and a molecule made of two carbon atoms g https://socialmedia.xdme.com/tony/videos-book8/page-104.mp4 https://www.youtube.com/embed/Y6l4xVXDmMQ 109 2026-10-04T02:13:49+00:00 yes https://xdme.com/watch-book8-q105.html https://xdme.com/book8-thumbs/page-105.jpg Why Does a Comet Move Fastest When It Passes Nearest the Sun? A comet moves fastest near the Sun because the Sun's gravity pulls harder when it is closer! The comet falls faster toward the Sun, then slows as it climbs away. It is like a rolle https://socialmedia.xdme.com/tony/videos-book8/page-105.mp4 https://www.youtube.com/embed/Akl0b2VKV-s 114 2026-10-04T02:13:52+00:00 yes https://xdme.com/watch-book8-q106.html https://xdme.com/book8-thumbs/page-106.jpg Why Do Asteroids and Comets Matter for Earth’s History? Asteroids and comets matter for Earth's history because their impacts helped shape our young planet! They may even have delivered water and organics, the chemical building blocks o https://socialmedia.xdme.com/tony/videos-book8/page-106.mp4 https://www.youtube.com/embed/LpIvZ8Eikew 118 2026-10-02T18:01:07+00:00 yes https://xdme.com/watch-book8-q107.html https://xdme.com/book8-thumbs/page-107.jpg Why Do Scientists Sample Asteroids with Spacecraft? Scientists sample asteroids with spacecraft because the grains are time capsules from the birth of the solar system! Asteroids have hardly changed in billions of years, so they kee https://socialmedia.xdme.com/tony/videos-book8/page-107.mp4 https://www.youtube.com/embed/P-qlDY8FmAY 118 2026-10-02T18:04:09+00:00 yes https://xdme.com/watch-book8-q108.html https://xdme.com/book8-thumbs/page-108.jpg Why Is Liquid Water a Big Deal When Hunting Life? Liquid water is a big deal when hunting for life because every living thing we know needs it! Water lets the chemicals inside living things mix, move, and react. Finding it elsewhe https://socialmedia.xdme.com/tony/videos-book8/page-108.mp4 https://www.youtube.com/embed/RA4sxERXCPs 118 2026-10-02T18:06:40+00:00 yes https://xdme.com/watch-book8-q109.html https://xdme.com/book8-thumbs/page-109.jpg Why Might Icy Moons Hide Oceans? Icy moons might hide oceans because a giant planet's pull can flex them and make heat inside! That inner warmth can melt some of the ice deep down. So under a thick ice shell, ther https://socialmedia.xdme.com/tony/videos-book8/page-109.mp4 https://www.youtube.com/embed/Qs1GTs6jAlk 113 2026-10-02T18:09:42+00:00 yes https://xdme.com/watch-book8-q110.html https://xdme.com/book8-thumbs/page-110.jpg Why Do Europa and Enceladus Excite Astrobiologists? Europa and Enceladus excite astrobiologists because they seem to hide oceans of liquid water! Astrobiologists are scientists who study the chances of life beyond Earth. Ocean world https://socialmedia.xdme.com/tony/videos-book8/page-110.mp4 https://www.youtube.com/embed/AZqeeeHUDrE 128 2026-10-02T18:12:44+00:00 yes https://xdme.com/watch-book8-q111.html https://xdme.com/book8-thumbs/page-111.jpg Why Haven’t We Found Definite Alien Life Yet? We haven't found definite alien life yet because space is vast, life may be rare, and our searches are still young! Not finding proof so far does not mean there is nothing out ther https://socialmedia.xdme.com/tony/videos-book8/page-111.mp4 https://www.youtube.com/embed/tPpcZgrZ8XY 117 2026-10-02T18:15:16+00:00 yes https://xdme.com/watch-book8-q112.html https://xdme.com/book8-thumbs/page-112.jpg Why Can Astronomers Find Planets They Can’t See? Astronomers can find planets they can't see by looking for wobbles and dips! A planet's gravity tugs its star, making it wobble. A planet crossing in front of the star blocks a lit https://socialmedia.xdme.com/tony/videos-book8/page-112.mp4 https://www.youtube.com/embed/88hZ_MhPkwA 113 2026-10-04T02:13:53+00:00 yes https://xdme.com/watch-book8-q113.html https://xdme.com/book8-thumbs/page-113.jpg Why Is the Habitable Zone Different Around Other Stars? The habitable zone is different around other stars because each star has a different heat! The habitable zone is the just-right distance where a planet could have liquid water. Hot https://socialmedia.xdme.com/tony/videos-book8/page-113.mp4 https://www.youtube.com/embed/1sDT9chJ8jo 112 2026-10-02T18:20:50+00:00 yes https://xdme.com/watch-book8-q114.html https://xdme.com/book8-thumbs/page-114.jpg Why Do SETI Projects Listen for Radio Signals? SETI projects listen for radio signals because radio waves can cross huge distances in space! SETI stands for Search for Extraterrestrial Intelligence. Scientists listen for patter https://socialmedia.xdme.com/tony/videos-book8/page-114.mp4 https://www.youtube.com/embed/u9g0canHRF0 122 2026-10-02T18:23:53+00:00 yes https://xdme.com/watch-book8-q115.html https://xdme.com/book8-thumbs/page-115.jpg Why Is Mars’s Methane a Curious Clue? Methane on Mars is a curious clue because it can come from geology or from tiny living microbes! Methane is a gas made of carbon and hydrogen. Spotting it makes scientists ask care https://socialmedia.xdme.com/tony/videos-book8/page-115.mp4 https://www.youtube.com/embed/twEJmUAYoks 118 2026-10-02T18:26:24+00:00 yes https://xdme.com/watch-book8-q116.html https://xdme.com/book8-thumbs/page-116.jpg Why Do Biosignatures Need Careful Checking? Biosignatures need careful checking because non-living chemistry can fake life-like signals! A biosignature is a sign that life might be present, like a certain gas or pattern. So https://socialmedia.xdme.com/tony/videos-book8/page-116.mp4 https://www.youtube.com/embed/htRSqyMs-Ew 123 2026-10-02T18:29:57+00:00 yes https://xdme.com/watch-book8-q117.html https://xdme.com/book8-thumbs/page-117.jpg Why Clean Spacecraft Before Visiting Ocean Worlds? We clean spacecraft before visiting ocean worlds so we don't bring Earth germs to alien seas! If Earth microbes hitched a ride, they could confuse our science and might even harm u https://socialmedia.xdme.com/tony/videos-book8/page-117.mp4 https://www.youtube.com/embed/3VuoKlTq_rw 120 2026-10-02T18:32:59+00:00 yes https://xdme.com/watch-book8-q118.html https://xdme.com/book8-thumbs/page-118.jpg Why Are Extremophiles on Earth Important for Space Biology? Extremophiles on Earth are important for space biology because they show how tough life can be! These are microbes that love acid, heat, salt, or cold. They help scientists imagine https://socialmedia.xdme.com/tony/videos-book8/page-118.mp4 https://www.youtube.com/embed/uR5iIMYYKu0 123 2026-10-02T18:35:31+00:00 yes https://xdme.com/watch-book8-q119.html https://xdme.com/book8-thumbs/page-119.jpg Why Do Meteor Showers Feel Safer than Asteroid Movies? Meteor showers feel safer than asteroid movies because shower meteors are tiny and burn up high in the sky! The streaks you see are usually grains of dust or sand, not big rocks. C https://socialmedia.xdme.com/tony/videos-book8/page-119.mp4 https://www.youtube.com/embed/4gShLp3pHIE 122 2026-10-02T18:38:33+00:00 yes https://xdme.com/watch-book8-q120.html https://xdme.com/book8-thumbs/page-120.jpg Why Do Comets Have Nuclei That Look Dark and Lumpy? Comet nuclei look dark and lumpy because they are dusty, rocky ices shaped by jets and time! Close-up photos from spacecraft show that they are not shiny ice cubes at all. A dirty https://socialmedia.xdme.com/tony/videos-book8/page-120.mp4 https://www.youtube.com/embed/4HxXH1Zsd14 119 2026-10-02T18:41:04+00:00 yes https://xdme.com/watch-book8-q121.html https://xdme.com/book8-thumbs/page-121.jpg Why Collect Antarctic Meteorites? Scientists collect Antarctic meteorites because dark rocks stand out on white ice, and moving ice gathers them together! Meteorites fall all over Earth, but they are hard to find i https://socialmedia.xdme.com/tony/videos-book8/page-121.mp4 https://www.youtube.com/embed/tVmjGN38UJQ 114 2026-10-02T18:44:07+00:00 yes https://xdme.com/watch-book8-q122.html https://xdme.com/book8-thumbs/page-122.jpg Why Might Organic Molecules Arrive From Space? Organic molecules might arrive from space because some meteorites and comets contain them! Organic molecules are carbon-based building blocks, like amino acids. Space chemistry can https://socialmedia.xdme.com/tony/videos-book8/page-122.mp4 https://www.youtube.com/embed/PAi0sqUa1Ow 122 2026-10-02T18:46:38+00:00 yes https://xdme.com/watch-book8-q123.html https://xdme.com/book8-thumbs/page-123.jpg Why Do Dust Tails of Comets Sometimes Cause Meteor Showers Later? Comets can cause meteor showers later because they leave dusty trails behind them! Earth crosses these old trails as it travels around the Sun. The crumbs hit our air, and we see t https://socialmedia.xdme.com/tony/videos-book8/page-123.mp4 https://www.youtube.com/embed/kqRU9WQaIlM 119 2026-10-02T18:49:40+00:00 yes https://xdme.com/watch-book8-q124.html https://xdme.com/book8-thumbs/page-124.jpg Why Map Near-Earth Asteroids? We map near-Earth asteroids so we can know their paths early and predict close approaches! Knowing where they travel lets us practice ideas for nudging an asteroid away, if that is https://socialmedia.xdme.com/tony/videos-book8/page-124.mp4 https://www.youtube.com/embed/OaXKdfpVUdQ 118 2026-10-02T18:52:12+00:00 yes https://xdme.com/watch-book8-q125.html https://xdme.com/book8-thumbs/page-125.jpg Why Keep Asking If We’re Alone? We keep asking if we're alone because it is one of science's biggest questions! Each careful search, on Mars, on moons, and around faraway stars, teaches us something. We learn abo https://socialmedia.xdme.com/tony/videos-book8/page-125.mp4 https://www.youtube.com/embed/NGE8Joxq1k0 121 2026-10-02T18:54:45+00:00 yes https://xdme.com/watch-book8-q126.html https://xdme.com/book8-thumbs/page-126.jpg Why Do Big Telescopes Use Mirrors Instead of Lenses? Telescopes use mirrors or lenses because they collect far more light than your eye and focus it! More light makes faint objects brighter, and focusing makes details sharper. A bigg https://socialmedia.xdme.com/tony/videos-book8/page-126.mp4 https://www.youtube.com/embed/faRvnlK2G74 118 2026-10-04T02:13:53+00:00 yes https://xdme.com/watch-book8-q127.html https://xdme.com/book8-thumbs/page-127.jpg Why Are Many Top Telescopes on Mountains? Many top telescopes are on mountains because the air up high is thinner, drier, and steadier! Higher, darker sites sit above much of the blurry, wet air and the glow of city lights https://socialmedia.xdme.com/tony/videos-book8/page-127.mp4 https://www.youtube.com/embed/9PgJrkk5q5g 115 2026-10-02T19:00:19+00:00 yes https://xdme.com/watch-book8-q128.html https://xdme.com/book8-thumbs/page-128.jpg Why Put Telescopes in Space? We put telescopes in space to get above the air that blurs and blocks starlight! Up there, there is no twinkle blur, and some kinds of light, like sharp ultraviolet or infrared, ge https://socialmedia.xdme.com/tony/videos-book8/page-128.mp4 https://www.youtube.com/embed/B-LuNPa4kGE 119 2026-10-02T19:02:52+00:00 yes https://xdme.com/watch-book8-q129.html https://xdme.com/book8-thumbs/page-129.jpg Why Does JWST See in Infrared? JWST sees in infrared because that light reveals things that our eyes and ordinary cameras miss! Infrared passes through dust clouds that hide baby stars, and it carries stretched https://socialmedia.xdme.com/tony/videos-book8/page-129.mp4 https://www.youtube.com/embed/zqmJpm8akhE 121 2026-10-02T19:05:54+00:00 yes https://xdme.com/watch-book8-q130.html https://xdme.com/book8-thumbs/page-130.jpg Why Do Radio Telescopes Look Like Giant Dishes? Radio telescopes look like giant dishes because radio waves are long, and you need a big collector to catch the faint ones! Space sends us very faint radio whispers from pulsars, g https://socialmedia.xdme.com/tony/videos-book8/page-130.mp4 https://www.youtube.com/embed/MD4TQ9wtzeA 119 2026-10-02T19:08:56+00:00 yes https://xdme.com/watch-book8-q131.html https://xdme.com/book8-thumbs/page-131.jpg Why Do Astronomers Use Filters and Many Wavelengths? Astronomers use filters and many wavelengths because each color and band of light shows something different! One kind of light may highlight hot gas, another cool dust, and another https://socialmedia.xdme.com/tony/videos-book8/page-131.mp4 https://www.youtube.com/embed/tldcabkGHgc 123 2026-10-02T19:11:27+00:00 yes https://xdme.com/watch-book8-q132.html https://xdme.com/book8-thumbs/page-132.jpg Why Can Adaptive Optics Cancel the Twinkle of Our Air? Adaptive optics cancels twinkle by measuring air blur and correcting it in real time! Special tools and a bendable mirror fix the blur many times a second. That makes ground telesc https://socialmedia.xdme.com/tony/videos-book8/page-132.mp4 https://www.youtube.com/embed/78xJ6DNX08U 112 2026-10-04T02:13:54+00:00 yes https://xdme.com/watch-book8-q133.html https://xdme.com/book8-thumbs/page-133.jpg Why Do Star Parties Share Telescopes? Star parties share telescopes so that everyone can learn and enjoy the night sky together! People bring their telescopes, show what they can see, and take turns looking. Nobody is https://socialmedia.xdme.com/tony/videos-book8/page-133.mp4 https://www.youtube.com/embed/Th8ShT-cdD8 118 2026-10-02T19:17:01+00:00 yes https://xdme.com/watch-book8-q134.html https://xdme.com/book8-thumbs/page-134.jpg Why Do Astronomers Write Down the Date, Time, and Place of Every Sighting? Astronomers write down the date, time, and place of every sighting, because patterns appear when you write things down! You can note the Moon's phases, planets, meteors, and the we https://socialmedia.xdme.com/tony/videos-book8/page-134.mp4 https://www.youtube.com/embed/fz9EmqUg50s 117 2026-10-04T02:13:55+00:00 yes https://xdme.com/watch-book8-q135.html https://xdme.com/book8-thumbs/page-135.jpg Why Do Planetarium Shows Help Even If They’re Not the Real Sky? Planetarium shows help even though they're not the real sky, because they teach you how to read it! They squeeze seasons into minutes, label constellations, and explain motions saf https://socialmedia.xdme.com/tony/videos-book8/page-135.mp4 https://www.youtube.com/embed/-LOMxYOMr40 116 2026-10-02T19:22:06+00:00 yes https://xdme.com/watch-book8-q136.html https://xdme.com/book8-thumbs/page-136.jpg Why Do Your Eyes Need 20 Minutes to See the Stars Well? Your eyes need 20 minutes to see the stars well because they slowly switch to night mode! In the dark, your eyes take about 20 minutes to become much more sensitive to light. A whi https://socialmedia.xdme.com/tony/videos-book8/page-136.mp4 https://www.youtube.com/embed/krwDkRmping 119 2026-10-04T02:13:56+00:00 yes https://xdme.com/watch-book8-q137.html https://xdme.com/book8-thumbs/page-137.jpg Why Do Apps Help , But Eyes Still Matter? Apps help us find and name things fast, but our eyes still matter, because the best detectives use both! Apps name stars and planets in a snap. But your eyes notice meteors, aurora https://socialmedia.xdme.com/tony/videos-book8/page-137.mp4 https://www.youtube.com/embed/gdhJNP8-xVQ 109 2026-10-02T19:27:39+00:00 yes https://xdme.com/watch-book8-q138.html https://xdme.com/book8-thumbs/page-138.jpg Why Do Spectroscopy Rainbows Reveal Star Recipes? Spectroscopy rainbows reveal star recipes, because gases leave fingerprint lines in starlight! When you spread starlight into a rainbow, dark or bright lines appear. Decode the lin https://socialmedia.xdme.com/tony/videos-book8/page-138.mp4 https://www.youtube.com/embed/YU1FeUUyMYc 120 2026-10-02T19:30:13+00:00 yes https://xdme.com/watch-book8-q139.html https://xdme.com/book8-thumbs/page-139.jpg Why Do Citizen Scientists Help Real Missions? Citizen scientists help real missions because people can spot patterns that computers sometimes miss! Space missions collect huge piles of pictures and data. Everyday volunteers he https://socialmedia.xdme.com/tony/videos-book8/page-139.mp4 https://www.youtube.com/embed/pYvNTbtK8_I 121 2026-10-02T19:33:17+00:00 yes https://xdme.com/watch-book8-q140.html https://xdme.com/book8-thumbs/page-140.jpg Why Measure the Sky in Magnitudes? We measure the sky in magnitudes because it gives everyone the same scale for brightness! In this system, smaller numbers mean brighter objects, and negative numbers mean super bri https://socialmedia.xdme.com/tony/videos-book8/page-140.mp4 https://www.youtube.com/embed/1Un1p4LidCA 121 2026-10-02T19:35:49+00:00 yes https://xdme.com/watch-book8-q141.html https://xdme.com/book8-thumbs/page-141.jpg Why Do Many Telescopes Sit Inside Domes with a Slot That Opens? Many telescopes sit inside domes to stay safe, and the slot opens so they can see the sky! A dome protects a telescope from wind, rain, and dust. The slot opens so the telescope ca https://socialmedia.xdme.com/tony/videos-book8/page-141.mp4 https://www.youtube.com/embed/liKjgI73uD0 116 2026-10-04T02:14:00+00:00 yes https://xdme.com/watch-book8-q142.html https://xdme.com/book8-thumbs/page-142.jpg Why Are Binoculars a Great First ‘Telescope’? Binoculars are a great first telescope because they are portable, show wide star fields, and need little fuss! With them you can see craters on the Moon and even moons around Jupit https://socialmedia.xdme.com/tony/videos-book8/page-142.mp4 https://www.youtube.com/embed/AWY8lyZXWtc 117 2026-10-02T19:41:23+00:00 yes https://xdme.com/watch-book8-q143.html https://xdme.com/book8-thumbs/page-143.jpg Why Align a Finderscope Before Hunting Planets? We align a finderscope before hunting planets, because it helps you center your target before you zoom in! A finderscope is a tiny scope on top that shows a wide view. Alignment sa https://socialmedia.xdme.com/tony/videos-book8/page-143.mp4 https://www.youtube.com/embed/QHjk6t5gb10 113 2026-10-02T19:44:25+00:00 yes https://xdme.com/watch-book8-q144.html https://xdme.com/book8-thumbs/page-144.jpg Why Do Some Images Use False Color? Some images use false color because scientists map invisible light to colors we can see! They also boost contrasts, so that hidden structures pop out. False color is a translation, https://socialmedia.xdme.com/tony/videos-book8/page-144.mp4 https://www.youtube.com/embed/XHtMJ-l7y4w 121 2026-10-02T19:47:27+00:00 yes https://xdme.com/watch-book8-q145.html https://xdme.com/book8-thumbs/page-145.jpg Why Collaborate Across Countries on Big Telescopes? Countries collaborate on big telescopes because giant observatories cost fortunes and need the very best sites! No single country wants to build everything alone, and few could. Sh https://socialmedia.xdme.com/tony/videos-book8/page-145.mp4 https://www.youtube.com/embed/v7_a0FYWceM 122 2026-10-02T19:50:00+00:00 yes https://xdme.com/watch-book8-q146.html https://xdme.com/book8-thumbs/page-146.jpg Why Can a Solar Storm Bother Satellites and Power Grids? A solar storm can bother satellites and power grids because it sends out charged particles! A burst of charged particles from the Sun can jostle Earth's magnetic field and disturb https://socialmedia.xdme.com/tony/videos-book8/page-146.mp4 https://www.youtube.com/embed/jo__EnuHz5s 119 2026-10-04T02:14:01+00:00 yes https://xdme.com/watch-book8-q147.html https://xdme.com/book8-thumbs/page-147.jpg Why Teach Kids to Question Viral ‘Planet’ Photos? We teach kids to question viral planet photos because many are art, composites, or mislabeled! Real sky detectives check the source, the scale, and the date. Skepticism is a scienc https://socialmedia.xdme.com/tony/videos-book8/page-147.mp4 https://www.youtube.com/embed/qYVKVZOsw0I 114 2026-10-02T19:56:04+00:00 yes https://xdme.com/watch-book8-q148.html https://xdme.com/book8-thumbs/page-148.jpg Why Do Light Pollution Laws and Dark-Sky Parks Help? Light pollution laws and dark-sky parks help, because smarter lighting keeps cities safe and stars visible! Dark-sky places protect night ecosystems, and they protect human wonder. https://socialmedia.xdme.com/tony/videos-book8/page-148.mp4 https://www.youtube.com/embed/NzK5fG4gifg 120 2026-10-04T02:14:02+00:00 yes https://xdme.com/watch-book8-q149.html https://xdme.com/book8-thumbs/page-149.jpg Why Is Patience Part of Astronomy? Patience is part of astronomy because clouds win some nights, and skills grow slowly! But the reward is worth it. You build a personal library of real sights that no screen can ful https://socialmedia.xdme.com/tony/videos-book8/page-149.mp4 https://www.youtube.com/embed/08H7hFauatQ 115 2026-10-02T20:01:07+00:00 yes https://xdme.com/watch-book8-q150.html https://xdme.com/book8-thumbs/page-150.jpg Why Does Every Space Answer Lead to a New Question? Every space answer leads to a new question because each discovery opens new puzzles! When astronomers find thousands of planets around other stars, they want to know what those pla https://socialmedia.xdme.com/tony/videos-book8/page-150.mp4 https://www.youtube.com/embed/9jHxvbNZhHw 115 2026-10-04T02:14:02+00:00 yes https://xdme.com/watch-book9-q001.html https://xdme.com/book9-thumbs/page-001.jpg Why Are Ice Cubes Cloudy in the Middle? Ice cubes are cloudy in the middle because freezing pushes tiny bubbles of air to the center! Water freezes from the outside in, and the air and minerals that were dissolved in the https://socialmedia.xdme.com/tony/videos-book9/page-001.mp4 https://www.youtube.com/embed/UKFOpRcX4LM 116 2026-10-02T21:12:32+00:00 yes https://xdme.com/watch-book9-q002.html https://xdme.com/book9-thumbs/page-002.jpg Why Does Ice Cream in a Bag Need Salty Ice? Ice cream in a bag needs salty ice because salt makes the ice colder than ice alone! Salty ice melts at a lower temperature, so the icy salt water gets colder than freezing. That s https://socialmedia.xdme.com/tony/videos-book9/page-002.mp4 https://www.youtube.com/embed/TWY_iNADG6c 118 2026-10-02T21:12:46+00:00 yes https://xdme.com/watch-book9-q003.html https://xdme.com/book9-thumbs/page-003.jpg Why Does Mayonnaise Stay Creamy When Oil and Water Usually Split? Mayonnaise stays creamy because egg yolk has emulsifiers that hold oil and water together! Oil and water usually push apart, but emulsifiers grab both of them. Tiny oil droplets st https://socialmedia.xdme.com/tony/videos-book9/page-003.mp4 https://www.youtube.com/embed/zyf2wyPzeFg 118 2026-10-02T21:12:47+00:00 yes https://xdme.com/watch-book9-q004.html https://xdme.com/book9-thumbs/page-004.jpg Why Does Pepper Run Away From a Drop of Dish Soap? Pepper runs away from soap because soap breaks the tight skin on the top of water! Water's surface is held tight by surface tension. Soap loosens that grip, so the water around it https://socialmedia.xdme.com/tony/videos-book9/page-004.mp4 https://www.youtube.com/embed/lByF5NbDAIo 119 2026-10-02T21:12:48+00:00 yes https://xdme.com/watch-book9-q005.html https://xdme.com/book9-thumbs/page-005.jpg Why Does Sugar Stop Dissolving If You Keep Adding It? Sugar stops dissolving because water can only hold so much of it! When the water is full, the extra sugar just sinks to the bottom. Warmer water can hold more, so it dissolves more https://socialmedia.xdme.com/tony/videos-book9/page-005.mp4 https://www.youtube.com/embed/oF45Scboi1o 114 2026-10-02T21:12:58+00:00 yes https://xdme.com/watch-book9-q006.html https://xdme.com/book9-thumbs/page-006.jpg Why Does Hot Cocoa Form a Skin on Top? Hot cocoa forms a skin on top because proteins and fats link together as water dries away! The top of the cup loses water into the air, so the milk proteins bunch up and join. That https://socialmedia.xdme.com/tony/videos-book9/page-006.mp4 https://www.youtube.com/embed/Cgarua4_TNc 110 2026-10-02T21:13:08+00:00 yes https://xdme.com/watch-book9-q007.html https://xdme.com/book9-thumbs/page-007.jpg Why Does a Drop of Water Make Hot Oil Spit and Pop? Water makes hot oil spit and pop because water turns into steam super fast! Water is heavier than oil, so it sinks and flashes into steam under the oil. The steam blasts hot oil dr https://socialmedia.xdme.com/tony/videos-book9/page-007.mp4 https://www.youtube.com/embed/VSgsOJk5N9Y 119 2026-10-02T21:13:11+00:00 yes https://xdme.com/watch-book9-q008.html https://xdme.com/book9-thumbs/page-008.jpg Why Does Lemon Juice Taste So Sour? Lemon juice tastes so sour because lemons are packed with citric acid! Acid switches on sour receptors on your tongue. It is a zingy warning and a big flavor punch, and kids often https://socialmedia.xdme.com/tony/videos-book9/page-008.mp4 https://www.youtube.com/embed/mVbH9SgpA4I 114 2026-10-02T21:13:18+00:00 yes https://xdme.com/watch-book9-q009.html https://xdme.com/book9-thumbs/page-009.jpg Why Does the Fizzy Mix of Baking Soda and Vinegar Get Cold? The fizzy mix of baking soda and vinegar gets cold because the reaction soaks up heat! As it makes carbon dioxide gas, it pulls warmth from the liquid. Not all reactions give off h https://socialmedia.xdme.com/tony/videos-book9/page-009.mp4 https://www.youtube.com/embed/Wx51a80S6fA 110 2026-10-02T21:13:20+00:00 yes https://xdme.com/watch-book9-q010.html https://xdme.com/book9-thumbs/page-010.jpg Why Does a Hard-Boiled Egg Get a Green-Gray Ring Around the Yolk? A hard-boiled egg gets a green-gray ring because sulfur from the white meets iron in the yolk! It happens when eggs cook for a long time. The ring is harmless, and cooling eggs qui https://socialmedia.xdme.com/tony/videos-book9/page-010.mp4 https://www.youtube.com/embed/R6goPy9385Q 109 2026-10-02T21:13:21+00:00 yes https://xdme.com/watch-book9-q011.html https://xdme.com/book9-thumbs/page-011.jpg Why Does Metal Feel Colder than Wood in the Same Room? Metal feels colder than wood because metal pulls heat out of your hand much faster! Both can be exactly the same temperature as the room. Wood is an insulator, so it pulls heat awa https://socialmedia.xdme.com/tony/videos-book9/page-011.mp4 https://www.youtube.com/embed/JbA3UZKkeqA 111 2026-10-02T21:13:23+00:00 yes https://xdme.com/watch-book9-q012.html https://xdme.com/book9-thumbs/page-012.jpg Why Do Tiny Bubbles Cling to the Pot Before the Water Boils? Tiny bubbles cling to the pot before boiling because air is leaving the water as it warms! Dissolved air cannot stay in warm water, so it forms bubbles on the pot. True boiling com https://socialmedia.xdme.com/tony/videos-book9/page-012.mp4 https://www.youtube.com/embed/Gr_s9Oz-L5E 114 2026-10-02T21:15:04+00:00 yes https://xdme.com/watch-book9-q013.html https://xdme.com/book9-thumbs/page-013.jpg Why Does Pasta Water Get Cloudy? Pasta water gets cloudy because starch leaks out of the noodles! Those tiny starch bits float in the water and make it look milky. Later they help sauces cling to pasta. https://socialmedia.xdme.com/tony/videos-book9/page-013.mp4 https://www.youtube.com/embed/v_AmF4jEcWw 110 2026-10-02T21:17:08+00:00 yes https://xdme.com/watch-book9-q014.html https://xdme.com/book9-thumbs/page-014.jpg Why Does Honey Turn Grainy and Hard in the Jar? Honey turns grainy and hard because some of its sugar slowly lines up into crystals! Honey is mostly sugar with very little water. It is still honey, and gentle warmth melts the cr https://socialmedia.xdme.com/tony/videos-book9/page-014.mp4 https://www.youtube.com/embed/9tnjV6vX5CY 115 2026-10-02T21:19:41+00:00 yes https://xdme.com/watch-book9-q015.html https://xdme.com/book9-thumbs/page-015.jpg Why Do Some Candies Feel Cold When They Dissolve? Some candies feel cold when they dissolve because dissolving takes heat from your mouth! Mint ingredients like menthol also trick your cold sensors. That makes a chilly feeling wit https://socialmedia.xdme.com/tony/videos-book9/page-015.mp4 https://www.youtube.com/embed/4-6ELNuQrGA 112 2026-10-02T21:22:28+00:00 yes https://xdme.com/watch-book9-q016.html https://xdme.com/book9-thumbs/page-016.jpg Why Does Bread Get Stale Even If It Isn’t Moldy? Bread gets stale even without mold because its starch slowly firms up! Moisture shifts around inside the loaf too. Stale is a change in texture, and it is not always spoilage. https://socialmedia.xdme.com/tony/videos-book9/page-016.mp4 https://www.youtube.com/embed/RzI5Me25XBw 114 2026-10-02T21:24:35+00:00 yes https://xdme.com/watch-book9-q017.html https://xdme.com/book9-thumbs/page-017.jpg Why Does Gelatin Turn Liquid Into Wobbly Solid? Gelatin turns liquid into a wobbly solid because proteins form a mesh that traps water! Warm liquid dissolves the gelatin proteins. Cooling lets them link into a net, which is dess https://socialmedia.xdme.com/tony/videos-book9/page-017.mp4 https://www.youtube.com/embed/F24t5z9wFs8 115 2026-10-02T21:27:39+00:00 yes https://xdme.com/watch-book9-q018.html https://xdme.com/book9-thumbs/page-018.jpg Why Do Fizzy Drinks Go Flat? Fizzy drinks go flat because the carbon dioxide gas escapes! When you open a bottle, the pressure drops and bubbles burst out. Warmth and stirring speed up the great gas getaway. https://socialmedia.xdme.com/tony/videos-book9/page-018.mp4 https://www.youtube.com/embed/CwtxtZya6aE 111 2026-10-02T21:30:14+00:00 yes https://xdme.com/watch-book9-q019.html https://xdme.com/book9-thumbs/page-019.jpg Why Does Whipping Cream Become Fluffy? Whipping cream becomes fluffy because whisking traps air in a network of fat! The fat clumps together a little and holds the bubbles in place. It makes a foam you can frost cakes w https://socialmedia.xdme.com/tony/videos-book9/page-019.mp4 https://www.youtube.com/embed/dWDASlC7a60 109 2026-10-02T21:32:17+00:00 yes https://xdme.com/watch-book9-q020.html https://xdme.com/book9-thumbs/page-020.jpg Why Does Lemon Juice Keep Cut Apples From Browning? Lemon juice keeps cut apples from browning because it slows the browning chemistry! It is acidic, and it holds vitamin C, which soaks up oxygen first. That keeps the apple pale and https://socialmedia.xdme.com/tony/videos-book9/page-020.mp4 https://www.youtube.com/embed/ZRIk_1NqnuI 113 2026-10-02T21:35:22+00:00 yes https://xdme.com/watch-book9-q021.html https://xdme.com/book9-thumbs/page-021.jpg Why Do Microwaved Foods Have Hot and Cold Spots? Microwaved food has hot and cold spots because microwaves make strong and weak spots inside the oven! The water in food heats up where the waves are strong. Stirring, turntables, a https://socialmedia.xdme.com/tony/videos-book9/page-021.mp4 https://www.youtube.com/embed/VLfdnAQuoj4 114 2026-10-02T21:37:54+00:00 yes https://xdme.com/watch-book9-q022.html https://xdme.com/book9-thumbs/page-022.jpg Why Does an Old Egg Float in Water? An old egg floats in water because a bigger pocket of air forms inside it over time! The shell has tiny pores, so water slowly escapes and air slips in. Floating is a hint about ag https://socialmedia.xdme.com/tony/videos-book9/page-022.mp4 https://www.youtube.com/embed/11bYGm8jl9M 108 2026-10-02T21:40:27+00:00 yes https://xdme.com/watch-book9-q023.html https://xdme.com/book9-thumbs/page-023.jpg Why Does Salt Make Food Taste More ‘Alive’? Salt makes food taste more alive because it boosts some flavors and balances bitterness! Used wisely, it helps your tongue notice more of the recipe, like turning up the volume on https://socialmedia.xdme.com/tony/videos-book9/page-023.mp4 https://www.youtube.com/embed/Dbnah7sdSJc 113 2026-10-02T21:43:00+00:00 yes https://xdme.com/watch-book9-q024.html https://xdme.com/book9-thumbs/page-024.jpg Why Does Yeast Need Sugar or Starch? Yeast needs sugar or starch because yeast are tiny living things that eat it! They eat sugars and release carbon dioxide gas and flavor. The gas bubbles make dough rise. https://socialmedia.xdme.com/tony/videos-book9/page-024.mp4 https://www.youtube.com/embed/WkE8YpUoUc4 111 2026-10-02T21:45:34+00:00 yes https://xdme.com/watch-book9-q025.html https://xdme.com/book9-thumbs/page-025.jpg Why Is Kitchen Chemistry Safe Science When You’re Careful? Kitchen chemistry is a safe way to explore science when you are careful and have a grown-up helping! Heat, sharp knives, and food allergies all need grown-up guidance. Curiosity pl https://socialmedia.xdme.com/tony/videos-book9/page-025.mp4 https://www.youtube.com/embed/HMVwTt59_Sk 116 2026-10-02T21:48:07+00:00 yes https://xdme.com/watch-book9-q026.html https://xdme.com/book9-thumbs/page-026.jpg Why Does Food Need Smell to Taste ‘Complete’? Food needs smell to taste complete because flavor is taste and smell working as a team! Your taste buds handle the basic tastes, but aroma molecules floating up to your nose build https://socialmedia.xdme.com/tony/videos-book9/page-026.mp4 https://www.youtube.com/embed/UVge_6nKst0 113 2026-10-02T21:50:40+00:00 yes https://xdme.com/watch-book9-q027.html https://xdme.com/book9-thumbs/page-027.jpg Why Is the ‘Tongue Map’ a Myth? The tongue map is a myth because every part of your tongue can taste every taste! Sweet, sour, salty, bitter, and umami receptors are scattered all around. Some spots have a few mo https://socialmedia.xdme.com/tony/videos-book9/page-027.mp4 https://www.youtube.com/embed/gaEOLCneJW4 114 2026-10-02T21:53:14+00:00 yes https://xdme.com/watch-book9-q028.html https://xdme.com/book9-thumbs/page-028.jpg Why Does Milk Calm a Spicy Mouth Better than Water? Milk calms a spicy mouth better than water because the spicy chemical dissolves in fat, not water! Milk has fat and a protein that bind that chemical and wash it away. Water just s https://socialmedia.xdme.com/tony/videos-book9/page-028.mp4 https://www.youtube.com/embed/-Do2m1hUL-M 114 2026-10-02T21:55:56+00:00 yes https://xdme.com/watch-book9-q029.html https://xdme.com/book9-thumbs/page-029.jpg Why Does Cold Water Feel Icier After You Eat Mint? Cold water feels icier after mint because menthol switches on your cold sensors! Those sensors then react more strongly to cool water. Your mouth is not colder, but the signal is l https://socialmedia.xdme.com/tony/videos-book9/page-029.mp4 https://www.youtube.com/embed/slvxs679Nuk 112 2026-10-02T21:58:29+00:00 yes https://xdme.com/watch-book9-q030.html https://xdme.com/book9-thumbs/page-030.jpg Why Do Cravings Happen? Cravings happen because body cues, habits, emotions, smells, and memories all nudge you to say, I want that! Not every craving means your body needs a certain nutrient. Cravings ar https://socialmedia.xdme.com/tony/videos-book9/page-030.mp4 https://www.youtube.com/embed/ptd2lESAfWA 108 2026-10-02T22:01:02+00:00 yes https://xdme.com/watch-book9-q031.html https://xdme.com/book9-thumbs/page-031.jpg Why Does Hunger Make Food Smell Stronger? Hunger makes food smell stronger because your brain turns up its attention to food cues! When you need energy, aromas suddenly seem louder and more persuasive. A hungry nose is a s https://socialmedia.xdme.com/tony/videos-book9/page-031.mp4 https://www.youtube.com/embed/i4Oz0arU7Q4 114 2026-10-02T22:04:05+00:00 yes https://xdme.com/watch-book9-q032.html https://xdme.com/book9-thumbs/page-032.jpg Why Is Umami Called the Fifth Taste? Umami is called the fifth taste because it was found after sweet, sour, salty, and bitter! It senses savory amino acids like glutamate in broths, tomatoes, and cheeses. Cooks use i https://socialmedia.xdme.com/tony/videos-book9/page-032.mp4 https://www.youtube.com/embed/fD6thfHotxM 126 2026-10-02T22:06:38+00:00 yes https://xdme.com/watch-book9-q033.html https://xdme.com/book9-thumbs/page-033.jpg Why Do Some People Dislike Bitter Greens? Some people dislike bitter greens because bitterness can warn of toxins, and sensitivity varies! Genes and experience change how strong bitter tastes feel. Cooking and dressings ca https://socialmedia.xdme.com/tony/videos-book9/page-033.mp4 https://www.youtube.com/embed/q6n6usb17OU 119 2026-10-02T22:09:41+00:00 yes https://xdme.com/watch-book9-q034.html https://xdme.com/book9-thumbs/page-034.jpg Why Does Orange Juice Taste Weird After Toothpaste? Orange juice tastes weird after toothpaste because toothpaste chemicals change how your tongue tastes! They suppress sweetness and boost bitter notes. The citrus tastes off until y https://socialmedia.xdme.com/tony/videos-book9/page-034.mp4 https://www.youtube.com/embed/rNHX6KDQ2YI 120 2026-10-02T22:12:14+00:00 yes https://xdme.com/watch-book9-q035.html https://xdme.com/book9-thumbs/page-035.jpg Why Do Fizzy Drinks Tingle? Fizzy drinks tingle because carbonation tickles your touch and pain sensors in a harmless way! Carbon dioxide turns into a mild acid called carbonic acid in your mouth. Bubbles add https://socialmedia.xdme.com/tony/videos-book9/page-035.mp4 https://www.youtube.com/embed/po2ymuM5ydI 117 2026-10-02T22:14:47+00:00 yes https://xdme.com/watch-book9-q036.html https://xdme.com/book9-thumbs/page-036.jpg Why Can the Smell of One Food Make You Feel Queasy Years Later? A smell can make you queasy years later because your brain links that smell with a bad memory! Maybe you felt sick after a meal, and your brain tries to protect you from repeating https://socialmedia.xdme.com/tony/videos-book9/page-036.mp4 https://www.youtube.com/embed/5qKjTtOH-HI 116 2026-10-02T22:17:57+00:00 yes https://xdme.com/watch-book9-q037.html https://xdme.com/book9-thumbs/page-037.jpg Why Does Food Taste Blander on an Airplane? Food tastes blander on an airplane because the dry, low-pressure cabin air dulls your senses! It dulls your sense of smell and makes taste buds less sensitive. Airlines often use b https://socialmedia.xdme.com/tony/videos-book9/page-037.mp4 https://www.youtube.com/embed/UdIwlHQHo34 115 2026-10-02T22:20:31+00:00 yes https://xdme.com/watch-book9-q038.html https://xdme.com/book9-thumbs/page-038.jpg Why Do Companies Design ‘Crunch’? Companies design crunch because sound and texture tell your brain that food is fresh! A loud, snappy crunch can make snacks feel more satisfying. Ears help you taste chips. https://socialmedia.xdme.com/tony/videos-book9/page-038.mp4 https://www.youtube.com/embed/3nB1OTmmY_g 111 2026-10-02T22:23:36+00:00 yes https://xdme.com/watch-book9-q039.html https://xdme.com/book9-thumbs/page-039.jpg Why Does Sweetness Make You Smile? Sweetness makes you smile because sweet foods used to signal ripe, energy-rich fruit for our ancestors! Brains still light up for sugar. But balance matters for health. https://socialmedia.xdme.com/tony/videos-book9/page-039.mp4 https://www.youtube.com/embed/JpnmB_7q_K4 117 2026-10-02T22:26:07+00:00 yes https://xdme.com/watch-book9-q040.html https://xdme.com/book9-thumbs/page-040.jpg Why Do Pickles Taste Sour and Salty Together? Pickles taste sour and salty together because the brine uses both salt and acid! The acid comes from vinegar or from fermentation. Both signals hit your tongue in one crunchy bite. https://socialmedia.xdme.com/tony/videos-book9/page-040.mp4 https://www.youtube.com/embed/tnpYU7YOutg 118 2026-10-02T22:28:40+00:00 yes https://xdme.com/watch-book9-q041.html https://xdme.com/book9-thumbs/page-041.jpg Why Does Smelling Food Make Your Mouth Water? Smelling food makes your mouth water because your body is getting ready to eat! The smell tells your brain that food is near, so it triggers saliva to help with chewing and tasting https://socialmedia.xdme.com/tony/videos-book9/page-041.mp4 https://www.youtube.com/embed/5YHg06BN8fI 111 2026-10-02T22:31:12+00:00 yes https://xdme.com/watch-book9-q042.html https://xdme.com/book9-thumbs/page-042.jpg Why Do Some Smells Seem ‘Loud’ Even in Tiny Amounts? Some smells seem loud even in tiny amounts because human noses can detect some molecules at super-low doses! Smells like toasted bread or vanilla are easy to notice. Our noses are https://socialmedia.xdme.com/tony/videos-book9/page-042.mp4 https://www.youtube.com/embed/uFCqqlTb1Qg 116 2026-10-02T22:34:16+00:00 yes https://xdme.com/watch-book9-q043.html https://xdme.com/book9-thumbs/page-043.jpg Why Does Temperature Change Flavor? Temperature changes flavor because cold mutes some aromas and sweetness, while warmth releases smells! Warm foods give off more volatile molecules, which are tiny scent pieces. Tha https://socialmedia.xdme.com/tony/videos-book9/page-043.mp4 https://www.youtube.com/embed/1sf_rvmHxfM 118 2026-10-02T22:37:20+00:00 yes https://xdme.com/watch-book9-q044.html https://xdme.com/book9-thumbs/page-044.jpg Why Do Kids’ Favorites Differ From Grown-Ups’? Kids' favorite foods differ from grown-ups' because sensitivity, exposure, culture, and learning shape what we like! Repeated gentle tries can expand the menu without force. Taste https://socialmedia.xdme.com/tony/videos-book9/page-044.mp4 https://www.youtube.com/embed/JVkWkkRoetg 117 2026-10-02T22:39:52+00:00 yes https://xdme.com/watch-book9-q045.html https://xdme.com/book9-thumbs/page-045.jpg Why Is Your Tongue Covered in Tiny Bumps? Your tongue is covered in tiny bumps called papillae, pah-PILL-ee! Some help grip food, and some hold taste buds. So your tongue is both a grabber and a taster. https://socialmedia.xdme.com/tony/videos-book9/page-045.mp4 https://www.youtube.com/embed/UzKL-YMUiBc 106 2026-10-02T22:42:26+00:00 yes https://xdme.com/watch-book9-q046.html https://xdme.com/book9-thumbs/page-046.jpg Why Can the Color of a Plate Change How Food Tastes? The color of a plate can change how food tastes because color sets your expectations! In one study, the same dessert tasted sweeter on a white plate than on a black plate. Your bra https://socialmedia.xdme.com/tony/videos-book9/page-046.mp4 https://www.youtube.com/embed/gMvRmfrmyCM 110 2026-10-02T22:44:59+00:00 yes https://xdme.com/watch-book9-q047.html https://xdme.com/book9-thumbs/page-047.jpg Why Does Salt on Caramel or Chocolate Work? Salt works on caramel or chocolate because opposite tastes can be teammates! A pinch of salt contrasts with sweetness and boosts your attention to aroma. Contrast makes flavors pop https://socialmedia.xdme.com/tony/videos-book9/page-047.mp4 https://www.youtube.com/embed/1PteNa1F6s8 116 2026-10-02T22:48:02+00:00 yes https://xdme.com/watch-book9-q048.html https://xdme.com/book9-thumbs/page-048.jpg Why Do You Get Tired of One Candy Flavor? You get tired of one candy flavor because your brain gets bored of the same flavor! A new taste feels exciting again. Variety wakes up your interest, even when you are still a bit https://socialmedia.xdme.com/tony/videos-book9/page-048.mp4 https://www.youtube.com/embed/TjvnM21bVwE 113 2026-10-02T22:51:06+00:00 yes https://xdme.com/watch-book9-q049.html https://xdme.com/book9-thumbs/page-049.jpg Why Does Smelling Vanilla Make Things Seem Sweeter? Smelling vanilla makes things seem sweeter because your brain mixes smell and taste! Our expectations about aroma nudge how sweet something seems. Vanilla scent can boost sweet wit https://socialmedia.xdme.com/tony/videos-book9/page-049.mp4 https://www.youtube.com/embed/8M4v66FX80E 112 2026-10-02T22:53:39+00:00 yes https://xdme.com/watch-book9-q050.html https://xdme.com/book9-thumbs/page-050.jpg Why Is Mindful Tasting a Superpower? Mindful tasting is a superpower because slowing down helps you notice aroma, texture, and fullness cues! Detectives gather more data about each bite. And you often enjoy food more. https://socialmedia.xdme.com/tony/videos-book9/page-050.mp4 https://www.youtube.com/embed/WV_k_uynfz4 112 2026-10-02T22:56:41+00:00 yes https://xdme.com/watch-book9-q051.html https://xdme.com/book9-thumbs/page-051.jpg Why Do Bakers Let Dough ‘Proof’ Before Baking? Bakers let dough proof before baking because yeast needs time to make gas and flavor! The dough stretches and fills with bubbles as it rests and rises. Proofing is the dough's rest https://socialmedia.xdme.com/tony/videos-book9/page-051.mp4 https://www.youtube.com/embed/f4Y9MY177Vg 109 2026-10-02T22:59:13+00:00 yes https://xdme.com/watch-book9-q052.html https://xdme.com/book9-thumbs/page-052.jpg Why Do Bakers Knead Dough? Bakers knead dough to line up gluten proteins into a stretchy, elastic network! That network holds bubbles and gives bread a pleasant chew. Under-kneaded bread can be dense. https://socialmedia.xdme.com/tony/videos-book9/page-052.mp4 https://www.youtube.com/embed/_19F56P_NHM 112 2026-10-02T23:02:17+00:00 yes https://xdme.com/watch-book9-q053.html https://xdme.com/book9-thumbs/page-053.jpg Why Does Gluten Matter in Wheat Bread? Gluten matters in wheat bread because it is the stretchy protein mesh that gives bread structure! Without it, loaves would not hold their bubbles. They would turn out flat and crum https://socialmedia.xdme.com/tony/videos-book9/page-053.mp4 https://www.youtube.com/embed/oJy3zoj_NTU 111 2026-10-02T23:04:49+00:00 yes https://xdme.com/watch-book9-q054.html https://xdme.com/book9-thumbs/page-054.jpg Why Do Some People Need Gluten-Free Bread? Some people need gluten-free bread because gluten makes them sick! Celiac disease and some sensitivities mean gluten can cause real health problems for them. Other flours and binde https://socialmedia.xdme.com/tony/videos-book9/page-054.mp4 https://www.youtube.com/embed/V1JZIl1sgXg 123 2026-10-02T23:07:52+00:00 yes https://xdme.com/watch-book9-q055.html https://xdme.com/book9-thumbs/page-055.jpg Why Do Some Recipes Need Both Baking Soda and Baking Powder? Some recipes need both baking soda and baking powder because they work in different ways! Baking soda needs an acid in the batter, like buttermilk, to make gas. Baking powder bring https://socialmedia.xdme.com/tony/videos-book9/page-055.mp4 https://www.youtube.com/embed/PQvnbya4sEo 119 2026-10-02T23:10:56+00:00 yes https://xdme.com/watch-book9-q056.html https://xdme.com/book9-thumbs/page-056.jpg Why Must Oven Spring Happen Fast? Oven spring must happen fast because early oven heat makes gases expand before the crust locks in! A good spring makes a taller loaf with a light, airy middle. A late set leaves a https://socialmedia.xdme.com/tony/videos-book9/page-056.mp4 https://www.youtube.com/embed/oOSDpeJFXZY 110 2026-10-02T23:13:30+00:00 yes https://xdme.com/watch-book9-q057.html https://xdme.com/book9-thumbs/page-057.jpg Why Are Some Cookies Chewy and Others Crispy? Some cookies are chewy and others are crispy because moisture decides it! Brown sugar, more butter, and a shorter bake keep cookies chewy. White sugar and a longer bake dry them in https://socialmedia.xdme.com/tony/videos-book9/page-057.mp4 https://www.youtube.com/embed/Tj7h-qAiRWc 113 2026-10-02T23:16:32+00:00 yes https://xdme.com/watch-book9-q058.html https://xdme.com/book9-thumbs/page-058.jpg Why Do Cooks Pat Food Dry Before Browning It? Cooks pat food dry before browning it because water keeps a food's surface near 100 degrees Celsius (212 degrees Fahrenheit)! Browning flavors need hotter temperatures. A dry surfa https://socialmedia.xdme.com/tony/videos-book9/page-058.mp4 https://www.youtube.com/embed/mjVUwb_9jEE 117 2026-10-02T23:19:19+00:00 yes https://xdme.com/watch-book9-q059.html https://xdme.com/book9-thumbs/page-059.jpg Why Does Caramel Need Careful Heat? Caramel needs careful heat because sugar goes from gold to burnt very fast! Sugar melts and browns through a process called caramelization, and a little too far makes it bitter. Me https://socialmedia.xdme.com/tony/videos-book9/page-059.mp4 https://www.youtube.com/embed/ZWg23qXEtro 117 2026-10-02T23:21:52+00:00 yes https://xdme.com/watch-book9-q060.html https://xdme.com/book9-thumbs/page-060.jpg Why Does Steam Help Some Bread Crusts? Steam helps some bread crusts because it keeps the outside flexible while the loaf expands! Later, the steam dries away and the crust turns into a crisp, shiny shell. Bakery ovens https://socialmedia.xdme.com/tony/videos-book9/page-060.mp4 https://www.youtube.com/embed/ce20FbSOJL8 115 2026-10-02T23:24:26+00:00 yes https://xdme.com/watch-book9-q061.html https://xdme.com/book9-thumbs/page-061.jpg Why Do Pancakes Make Bubbles That ‘Tell You’ to Flip? Pancake bubbles tell you when to flip because they show that the underside has set! Gas and steam form bubbles that pop on top when the bottom is firm. Bubble clues beat random fli https://socialmedia.xdme.com/tony/videos-book9/page-061.mp4 https://www.youtube.com/embed/5v0ZWleOmMs 111 2026-10-02T23:27:30+00:00 yes https://xdme.com/watch-book9-q062.html https://xdme.com/book9-thumbs/page-062.jpg Why Does Sourdough Smell Tangy? Sourdough smells tangy because wild yeast and lactic acid bacteria ferment the dough! They make acids and complex aromas. Tang is fermentation's signature. https://socialmedia.xdme.com/tony/videos-book9/page-062.mp4 https://www.youtube.com/embed/BQgoZUoWaOI 114 2026-10-02T23:30:14+00:00 yes https://xdme.com/watch-book9-q063.html https://xdme.com/book9-thumbs/page-063.jpg Why Rest Cookie Dough in the Fridge? Cookie dough rests in the fridge because flour soaks up water, fats firm up, and flavors mellow! Chilled dough spreads less in the oven. It can also taste deeper. https://socialmedia.xdme.com/tony/videos-book9/page-063.mp4 https://www.youtube.com/embed/i_QaOomf2eY 108 2026-10-02T23:32:47+00:00 yes https://xdme.com/watch-book9-q064.html https://xdme.com/book9-thumbs/page-064.jpg Why Do Muffins Get Tunnels If You Mix Too Much? Muffins get tunnels when you mix too much because overmixing builds extra gluten and big gas tunnels! Gentle mixing keeps the crumb tender and even. Lumps can be okay in muffin bat https://socialmedia.xdme.com/tony/videos-book9/page-064.mp4 https://www.youtube.com/embed/dMCDIlRcAWE 109 2026-10-02T23:35:50+00:00 yes https://xdme.com/watch-book9-q065.html https://xdme.com/book9-thumbs/page-065.jpg Why Does Pie Dough Like Cold Butter? Pie dough likes cold butter because cold butter chunks melt in the oven and leave flaky steam pockets! Warm butter blends in completely. That can make a crust tough or greasy. https://socialmedia.xdme.com/tony/videos-book9/page-065.mp4 https://www.youtube.com/embed/1Db3o9uMIbw 105 2026-10-02T23:38:24+00:00 yes https://xdme.com/watch-book9-q066.html https://xdme.com/book9-thumbs/page-066.jpg Why Can a Slammed Oven Door Make a Cake Fall? A cake can fall after a slammed oven door because a baking cake is very fragile at the start! It is full of tiny air bubbles that hold it up. A sudden bang or a rush of cool air ca https://socialmedia.xdme.com/tony/videos-book9/page-066.mp4 https://www.youtube.com/embed/9E0pbtTaqwg 104 2026-10-02T23:40:57+00:00 yes https://xdme.com/watch-book9-q067.html https://xdme.com/book9-thumbs/page-067.jpg Why Measure Flour Carefully? We measure flour carefully because the same cup can hold very different amounts of flour! Too much flour makes baked goods dry and tough. Weighing flour on a scale gives the same a https://socialmedia.xdme.com/tony/videos-book9/page-067.mp4 https://www.youtube.com/embed/f_vtKrAc_1I 111 2026-10-02T23:44:00+00:00 yes https://xdme.com/watch-book9-q068.html https://xdme.com/book9-thumbs/page-068.jpg Why Does Yeast Need Warm Water, Not Hot? Yeast needs warm water, not hot, because yeast is a tiny living thing! Warm water wakes it up, but very hot water can kill it. Dead yeast cannot make bread rise. https://socialmedia.xdme.com/tony/videos-book9/page-068.mp4 https://www.youtube.com/embed/ulBjwd2HNtw 116 2026-10-02T23:46:39+00:00 yes https://xdme.com/watch-book9-q069.html https://xdme.com/book9-thumbs/page-069.jpg Why Do Bagels Get Boiled Before Baking? Bagels get boiled before baking because the quick bath sets the outside of the dough! That makes bagels chewy and shiny. Without it, they would puff up into soft rolls. https://socialmedia.xdme.com/tony/videos-book9/page-069.mp4 https://www.youtube.com/embed/mWxcFNJ4jEE 108 2026-10-02T23:50:11+00:00 yes https://xdme.com/watch-book9-q070.html https://xdme.com/book9-thumbs/page-070.jpg Why Does Laminated Dough Make Croissants Flaky? Laminated dough makes croissants flaky because it has many thin layers of butter and dough! Laminated means made of layers. In the oven, the layers puff apart into crispy leaves. https://socialmedia.xdme.com/tony/videos-book9/page-070.mp4 https://www.youtube.com/embed/ly4ofcGahCY 109 2026-10-02T23:53:47+00:00 yes https://xdme.com/watch-book9-q071.html https://xdme.com/book9-thumbs/page-071.jpg Why Do Ovens Have Hot Spots? Ovens have hot spots because the heat inside is not perfectly even! Some corners are hotter than others. That is why cookies in one spot can brown faster than cookies in another. https://socialmedia.xdme.com/tony/videos-book9/page-071.mp4 https://www.youtube.com/embed/vkT75oU_j2M 113 2026-10-02T23:56:19+00:00 yes https://xdme.com/watch-book9-q072.html https://xdme.com/book9-thumbs/page-072.jpg Why Does Altitude Change Baking Recipes? Altitude changes baking recipes because the air up high is thinner! Thinner air has less pressure pushing down. That changes how fast batter rises and how fast water boils and drie https://socialmedia.xdme.com/tony/videos-book9/page-072.mp4 https://www.youtube.com/embed/Zbb4Xdi5CQA 116 2026-10-02T23:59:23+00:00 yes https://xdme.com/watch-book9-q073.html https://xdme.com/book9-thumbs/page-073.jpg Why Do We Grease or Paper Pans? We grease pans or use paper because baked food likes to stick to metal! A thin layer of fat or a paper liner keeps the batter from gluing on. Then muffins slide out whole and clean https://socialmedia.xdme.com/tony/videos-book9/page-073.mp4 https://www.youtube.com/embed/mmjSkJm2rpI 109 2026-10-03T00:01:56+00:00 yes https://xdme.com/watch-book9-q074.html https://xdme.com/book9-thumbs/page-074.jpg Why Does Bread Sing When It Cools? Fresh bread can sing when it cools because the crust crackles as it changes! The crackling sounds like a tiny song. Bakers listen for it as a sign of a good bake. https://socialmedia.xdme.com/tony/videos-book9/page-074.mp4 https://www.youtube.com/embed/V3tu4TGm3C0 108 2026-10-03T00:04:36+00:00 yes https://xdme.com/watch-book9-q075.html https://xdme.com/book9-thumbs/page-075.jpg Why Is Sharing Baked Bread a Science Celebration? Sharing baked bread is a science celebration because bread is an edible experiment! You turned flour, water, and tiny living yeast into something new. That is chemistry you can but https://socialmedia.xdme.com/tony/videos-book9/page-075.mp4 https://www.youtube.com/embed/lU5sqs8VRuo 111 2026-10-03T00:07:38+00:00 yes https://xdme.com/watch-book9-q076.html https://xdme.com/book9-thumbs/page-076.jpg Why Are Fruits Often Sweet When Ripe? Fruits are often sweet when ripe because plants are making a tasty advertisement! Inside a fruit are seeds, and the plant wants animals to carry them far away. Sweet sugar is the p https://socialmedia.xdme.com/tony/videos-book9/page-076.mp4 https://www.youtube.com/embed/MOApL93rqc4 117 2026-10-02T21:13:26+00:00 yes https://xdme.com/watch-book9-q077.html https://xdme.com/book9-thumbs/page-077.jpg Why Do Bananas Ripen in a Bag Faster? Bananas ripen faster in a bag because they make a gas that tells fruit to ripen! The gas is called ethylene, and it floats out of the banana. A bag traps the gas close, so the frui https://socialmedia.xdme.com/tony/videos-book9/page-077.mp4 https://www.youtube.com/embed/mCUJ2g8arrs 117 2026-10-02T21:13:27+00:00 yes https://xdme.com/watch-book9-q078.html https://xdme.com/book9-thumbs/page-078.jpg Why Is a Tomato a Fruit to Scientists? A tomato is a fruit to scientists because of how it grows! In plant science, a fruit grows from a flower and holds seeds inside. A tomato does exactly that, even though cooks call https://socialmedia.xdme.com/tony/videos-book9/page-078.mp4 https://www.youtube.com/embed/KYN9tRuxhCE 116 2026-10-02T21:13:28+00:00 yes https://xdme.com/watch-book9-q079.html https://xdme.com/book9-thumbs/page-079.jpg Why Do Leafy Greens Wilt in the Fridge? Leafy greens wilt in the fridge because they lose water! Their cells are like tiny balloons filled with water, and the water keeps leaves crisp. When the water leaks out into dry a https://socialmedia.xdme.com/tony/videos-book9/page-079.mp4 https://www.youtube.com/embed/gdRxXHDim_o 112 2026-10-02T21:13:30+00:00 yes https://xdme.com/watch-book9-q080.html https://xdme.com/book9-thumbs/page-080.jpg Why Are Carrots Orange? Carrots are orange because they are packed with an orange pigment called beta-carotene! Your body turns it into vitamin A, which helps your eyes and skin. Long ago, carrots also ca https://socialmedia.xdme.com/tony/videos-book9/page-080.mp4 https://www.youtube.com/embed/ldmJ7RhG6ww 121 2026-10-02T21:13:31+00:00 yes https://xdme.com/watch-book9-q081.html https://xdme.com/book9-thumbs/page-081.jpg Why Do Carrots Taste Sweeter After a Frost? Carrots taste sweeter after a frost because the cold makes them turn stored starch into sugar! Starch tastes plain, but sugar helps protect the carrot from freezing. That is why a https://socialmedia.xdme.com/tony/videos-book9/page-081.mp4 https://www.youtube.com/embed/dv34F8yuIls 120 2026-10-02T21:13:45+00:00 yes https://xdme.com/watch-book9-q082.html https://xdme.com/book9-thumbs/page-082.jpg Why Soak Beans Before Cooking? We soak dried beans because a dry bean is a sleeping seed that needs water to wake up! Soaking lets water move inside, so the bean softens and cooks in less time. But beans must al https://socialmedia.xdme.com/tony/videos-book9/page-082.mp4 https://www.youtube.com/embed/4AlsWJMmtww 117 2026-10-02T21:13:46+00:00 yes https://xdme.com/watch-book9-q083.html https://xdme.com/book9-thumbs/page-083.jpg Why Do Apples Float? Apples float because they have tiny pockets of air inside! That air makes an apple less dense than water, so water pushes it up. Bobbing for apples at a party is really density sci https://socialmedia.xdme.com/tony/videos-book9/page-083.mp4 https://www.youtube.com/embed/4hYxTpWOOP4 111 2026-10-02T21:13:48+00:00 yes https://xdme.com/watch-book9-q084.html https://xdme.com/book9-thumbs/page-084.jpg Why Are Chili Peppers Spicy for Mammals But Not Birds? Chili peppers burn our mouths but not birds' beaks! The spicy chemical is called capsaicin, and mammals feel it as heat and pain. Birds barely notice it, so they can eat the pepper https://socialmedia.xdme.com/tony/videos-book9/page-084.mp4 https://www.youtube.com/embed/j4W1AyokGXk 120 2026-10-02T21:13:50+00:00 yes https://xdme.com/watch-book9-q085.html https://xdme.com/book9-thumbs/page-085.jpg Why Do Onions and Garlic Make Savory Magic? Onions and garlic make savory magic because chopping and cooking change their chemicals! Whole onions and garlic hold sulfur compounds that are mostly locked away. Cutting and cook https://socialmedia.xdme.com/tony/videos-book9/page-085.mp4 https://www.youtube.com/embed/SYMu9eNNf5A 120 2026-10-02T21:13:52+00:00 yes https://xdme.com/watch-book9-q086.html https://xdme.com/book9-thumbs/page-086.jpg Why Is Fiber in Plants Helpful? Fiber in plants is helpful because it helps food move through your body and feeds friendly gut microbes! Fiber is the part of plants that your body cannot fully digest, and that is https://socialmedia.xdme.com/tony/videos-book9/page-086.mp4 https://www.youtube.com/embed/wjCfk7MvM_M 114 2026-10-02T21:13:55+00:00 yes https://xdme.com/watch-book9-q087.html https://xdme.com/book9-thumbs/page-087.jpg Why Do Potatoes Turn Green in Light? Potatoes turn green in light because they make green chlorophyll when they sit in the light! The green color itself is harmless, but the same light can also raise a bitter compound https://socialmedia.xdme.com/tony/videos-book9/page-087.mp4 https://www.youtube.com/embed/JaF-ALZjYJk 119 2026-10-02T21:15:07+00:00 yes https://xdme.com/watch-book9-q088.html https://xdme.com/book9-thumbs/page-088.jpg Why Sprout Seeds on a Windowsill? We sprout seeds on a windowsill to watch a plant wake up! A seed holds a tiny baby plant called an embryo, plus stored food. Warmth, water, and air tell it that it is time to grow. https://socialmedia.xdme.com/tony/videos-book9/page-088.mp4 https://www.youtube.com/embed/k2W1UIFK5jU 109 2026-10-02T21:17:09+00:00 yes https://xdme.com/watch-book9-q089.html https://xdme.com/book9-thumbs/page-089.jpg Why Are Berries Often Tiny and Many? Berries are often tiny and many because small fruits can send out lots of seeds! A plant that makes many berries gets many chances to have its seeds carried away. More tries means https://socialmedia.xdme.com/tony/videos-book9/page-089.mp4 https://www.youtube.com/embed/tu6ZP3--3Nc 120 2026-10-02T21:19:56+00:00 yes https://xdme.com/watch-book9-q090.html https://xdme.com/book9-thumbs/page-090.jpg Why Do Dried Lentils Cook Faster than Dried Chickpeas? Dried lentils cook faster than dried chickpeas because they are smaller and thinner! Both are seeds called legumes, but they are built differently. Size, coat thickness, and starch https://socialmedia.xdme.com/tony/videos-book9/page-090.mp4 https://www.youtube.com/embed/EbtLZ93eDEc 116 2026-10-02T21:22:34+00:00 yes https://xdme.com/watch-book9-q091.html https://xdme.com/book9-thumbs/page-091.jpg Why Do Herbs Smell Strong When Rubbed? Herbs smell strong when rubbed because rubbing breaks tiny oil bags in the leaf! Those oils are full of aroma molecules that float into the air and into your nose. It is like openi https://socialmedia.xdme.com/tony/videos-book9/page-091.mp4 https://www.youtube.com/embed/ygUtuQRBtyM 115 2026-10-02T21:25:06+00:00 yes https://xdme.com/watch-book9-q092.html https://xdme.com/book9-thumbs/page-092.jpg Why Is Corn a Seed, a Grain, and a Vegetable Depending on Talk? Corn can be a seed, a grain, and a vegetable because the words depend on how we use it! Botanically, a corn kernel is a seed. Cooks and farmers use different words for different jo https://socialmedia.xdme.com/tony/videos-book9/page-092.mp4 https://www.youtube.com/embed/idZUsQ_9vZA 116 2026-10-02T21:27:42+00:00 yes https://xdme.com/watch-book9-q093.html https://xdme.com/book9-thumbs/page-093.jpg Why Do Cucumbers Feel Cool? Cucumbers feel cool because they are mostly water! A cucumber is about 95 percent water, so a bite is crisp, wet, and refreshing. Plus, you often eat cucumbers chilled from the fri https://socialmedia.xdme.com/tony/videos-book9/page-093.mp4 https://www.youtube.com/embed/LXeRKflfZEI 116 2026-10-02T21:30:15+00:00 yes https://xdme.com/watch-book9-q094.html https://xdme.com/book9-thumbs/page-094.jpg Why Ferment Cabbage Into Sauerkraut? We ferment cabbage into sauerkraut to make it tangy and last longer! Salt pulls juice out of the cabbage, and friendly bacteria in that juice make acid. That acid keeps the cabbage https://socialmedia.xdme.com/tony/videos-book9/page-094.mp4 https://www.youtube.com/embed/2hXczLCvPq4 118 2026-10-02T21:32:49+00:00 yes https://xdme.com/watch-book9-q095.html https://xdme.com/book9-thumbs/page-095.jpg Why Are Mushrooms Neither Fruits Nor Veggies Exactly? Mushrooms are not exactly fruits or vegetables because they are fungi! Fungi are their own kingdom of life, separate from plants and animals. We cook mushrooms like produce, but th https://socialmedia.xdme.com/tony/videos-book9/page-095.mp4 https://www.youtube.com/embed/6fBvETDUrx4 122 2026-10-02T21:35:23+00:00 yes https://xdme.com/watch-book9-q096.html https://xdme.com/book9-thumbs/page-096.jpg Why Blanch Veggies Before Freezing? We blanch veggies before freezing them to keep their color, flavor, and crunch! Blanching means dipping veggies in boiling water for a short time, then moving them to ice water. It https://socialmedia.xdme.com/tony/videos-book9/page-096.mp4 https://www.youtube.com/embed/mf46B4pVIk0 120 2026-10-02T21:37:56+00:00 yes https://xdme.com/watch-book9-q097.html https://xdme.com/book9-thumbs/page-097.jpg Why Do Citrus Peels Smell Stronger than the Juicy Insides? Citrus peels smell stronger because the peel is packed with little oil glands! The oils are full of aroma molecules, so the outside is a super-powered perfume. The juicy inside is https://socialmedia.xdme.com/tony/videos-book9/page-097.mp4 https://www.youtube.com/embed/T2m-ySpJfmg 113 2026-10-02T21:40:29+00:00 yes https://xdme.com/watch-book9-q098.html https://xdme.com/book9-thumbs/page-098.jpg Why Rotate Crops on Farms? Farmers rotate crops, which means they grow different plants in a field each year! Different plants take and give back different nutrients, and they face different pests. Rotation https://socialmedia.xdme.com/tony/videos-book9/page-098.mp4 https://www.youtube.com/embed/CTih5lov3Nk 118 2026-10-02T21:43:02+00:00 yes https://xdme.com/watch-book9-q099.html https://xdme.com/book9-thumbs/page-099.jpg Why Does Red Cabbage Juice Change Color with Lemon or Baking Soda? Red cabbage juice changes color because it contains pigments that react to acids and bases! It turns pink with acids like lemon juice, and blue-green with bases like baking soda. I https://socialmedia.xdme.com/tony/videos-book9/page-099.mp4 https://www.youtube.com/embed/4CJLjy4qZQ4 116 2026-10-02T21:45:36+00:00 yes https://xdme.com/watch-book9-q100.html https://xdme.com/book9-thumbs/page-100.jpg Why Thank Plants at Dinner? We thank plants at dinner because plants turn sunlight into food! Leaves, roots, seeds, and fruits all come from plants making food through photosynthesis, a word that means puttin https://socialmedia.xdme.com/tony/videos-book9/page-100.mp4 https://www.youtube.com/embed/3cA4nTngoVI 119 2026-10-02T21:48:09+00:00 yes https://xdme.com/watch-book9-q101.html https://xdme.com/book9-thumbs/page-101.jpg Why Do Farms Use Soil So Carefully? Farms use soil carefully because soil is a living factory that grows our food! It holds water, nutrients, and billions of tiny microbes that plants need. Healthy soil grows stronge https://socialmedia.xdme.com/tony/videos-book9/page-101.mp4 https://www.youtube.com/embed/P4kndM8cfeg 116 2026-10-02T21:50:42+00:00 yes https://xdme.com/watch-book9-q102.html https://xdme.com/book9-thumbs/page-102.jpg Why Irrigate Fields? Farmers irrigate fields to give crops steady water when rain does not come! Plants need water to grow, make food, and fill their fruits and seeds. Irrigation delivers water at the https://socialmedia.xdme.com/tony/videos-book9/page-102.mp4 https://www.youtube.com/embed/XZvtwA17TAo 124 2026-10-02T21:53:55+00:00 yes https://xdme.com/watch-book9-q103.html https://xdme.com/book9-thumbs/page-103.jpg Why Do Bees Matter for So Many Foods? Bees matter for so many foods because they pollinate flowers! Pollination helps plants make fruits, seeds, and nuts. With no pollination, there would be far fewer groceries, and ma https://socialmedia.xdme.com/tony/videos-book9/page-103.mp4 https://www.youtube.com/embed/poD_Gp9bfko 118 2026-10-02T21:55:58+00:00 yes https://xdme.com/watch-book9-q104.html https://xdme.com/book9-thumbs/page-104.jpg Why Harvest at Peak Ripeness for Some Crops? Farmers harvest some crops at peak ripeness because flavor and nutrients are best at that moment! After the peak, fruit gets overripe, soft, and may spoil. So picking time is a rac https://socialmedia.xdme.com/tony/videos-book9/page-104.mp4 https://www.youtube.com/embed/FX3BXbUiVR8 121 2026-10-02T21:59:01+00:00 yes https://xdme.com/watch-book9-q105.html https://xdme.com/book9-thumbs/page-105.jpg Why Do Farms and Stores Chill Milk and Meat Quickly? Farms and stores chill milk and meat quickly because cold slows down bacteria! Bacteria grow fast in warm places and slowly in cold ones. Fast cooling keeps these foods safe from t https://socialmedia.xdme.com/tony/videos-book9/page-105.mp4 https://www.youtube.com/embed/BQqUtRBUfSs 116 2026-10-02T22:01:33+00:00 yes https://xdme.com/watch-book9-q106.html https://xdme.com/book9-thumbs/page-106.jpg Why Pasteurize Milk? We pasteurize milk to make it much safer to drink! Pasteurizing means heating milk gently to kill harmful microbes. It is named after the French scientist Louis Pasteur, who showed https://socialmedia.xdme.com/tony/videos-book9/page-106.mp4 https://www.youtube.com/embed/Ttn7MCp6k8w 118 2026-10-02T22:04:06+00:00 yes https://xdme.com/watch-book9-q107.html https://xdme.com/book9-thumbs/page-107.jpg Why Do Eggs Have Dates on Cartons? Eggs have dates on cartons to help stores and families use them while they are freshest! Dates help stores rotate stock, so older cartons are sold first. But how you store eggs mat https://socialmedia.xdme.com/tony/videos-book9/page-107.mp4 https://www.youtube.com/embed/bVdiN2Gy--w 112 2026-10-02T22:06:39+00:00 yes https://xdme.com/watch-book9-q108.html https://xdme.com/book9-thumbs/page-108.jpg Why Truck, Ship, and Fly Food Around the World? We truck, ship, and fly food around the world because climate and seasons limit what grows nearby! Bananas need warm weather, while apples need cool winters. Transport brings varie https://socialmedia.xdme.com/tony/videos-book9/page-108.mp4 https://www.youtube.com/embed/o9-vwO81zL0 118 2026-10-02T22:09:42+00:00 yes https://xdme.com/watch-book9-q109.html https://xdme.com/book9-thumbs/page-109.jpg Why Do ‘Food Miles’ Matter to Some Families? Food miles matter to some families because they measure how far food travels to reach you! More distance can mean more fuel use and more pollution. Local, seasonal food can lower m https://socialmedia.xdme.com/tony/videos-book9/page-109.mp4 https://www.youtube.com/embed/kM4UFV4i5ok 112 2026-10-02T22:12:15+00:00 yes https://xdme.com/watch-book9-q110.html https://xdme.com/book9-thumbs/page-110.jpg Why Package Foods in Different Materials? Foods come in different packages because each material protects in a different way! Glass, cans, cardboard, and plastics guard against light, air, pests, and crushing. But each has https://socialmedia.xdme.com/tony/videos-book9/page-110.mp4 https://www.youtube.com/embed/Au79lGlLRbo 124 2026-10-02T22:15:18+00:00 yes https://xdme.com/watch-book9-q111.html https://xdme.com/book9-thumbs/page-111.jpg Why Do People Can Food in Jars and Cans? People can food in jars and cans to keep it safe for a very long time! Heat-sealing kills microbes and blocks new ones from getting in, so the food needs no fridge until it is open https://socialmedia.xdme.com/tony/videos-book9/page-111.mp4 https://www.youtube.com/embed/hORpbnIdV9s 120 2026-10-02T22:18:00+00:00 yes https://xdme.com/watch-book9-q112.html https://xdme.com/book9-thumbs/page-112.jpg Why Freeze Vegetables? We freeze vegetables to pause spoilage and keep them tasty for months! Cold slows microbes and slows the changes that make food lose quality. Peak-season produce can taste great lo https://socialmedia.xdme.com/tony/videos-book9/page-112.mp4 https://www.youtube.com/embed/MilCbxHi2iw 119 2026-10-02T22:20:33+00:00 yes https://xdme.com/watch-book9-q113.html https://xdme.com/book9-thumbs/page-113.jpg Why Do Grocery Stores Mist Veggies? Grocery stores mist veggies to add humidity so leaves stay crisp and fresh-looking! Leafy greens lose water quickly in dry store air, and then they wilt. A little mist helps, but t https://socialmedia.xdme.com/tony/videos-book9/page-113.mp4 https://www.youtube.com/embed/W-pKMLER3nQ 117 2026-10-02T22:23:04+00:00 yes https://xdme.com/watch-book9-q114.html https://xdme.com/book9-thumbs/page-114.jpg Why Are Grocery Stores Laid Out the Way They Are? Grocery stores are laid out carefully so you can find what you need and discover new things! Where things sit is a mix of shopping psychology and logistics, like keeping cold foods https://socialmedia.xdme.com/tony/videos-book9/page-114.mp4 https://www.youtube.com/embed/RidlIMDqQks 119 2026-10-02T22:26:08+00:00 yes https://xdme.com/watch-book9-q115.html https://xdme.com/book9-thumbs/page-115.jpg Why Do Bakers Start Before Dawn? Bakers start before dawn so fresh bread is ready for morning customers! Dough needs hours to rise, and ovens have limited space. A baker's day runs on ingredient clocks, which mean https://socialmedia.xdme.com/tony/videos-book9/page-115.mp4 https://www.youtube.com/embed/1e7czFNIP0o 114 2026-10-02T22:28:41+00:00 yes https://xdme.com/watch-book9-q116.html https://xdme.com/book9-thumbs/page-116.jpg Why Does a Package Say ‘May Contain Traces of Nuts’? A package says may contain traces of nuts to warn people with serious allergies! Factories sometimes make nut foods and other foods on the same equipment, so tiny traces can sneak https://socialmedia.xdme.com/tony/videos-book9/page-116.mp4 https://www.youtube.com/embed/rIwKMw-QNsw 121 2026-10-02T22:31:44+00:00 yes https://xdme.com/watch-book9-q117.html https://xdme.com/book9-thumbs/page-117.jpg Why Refrigerate Leftovers Promptly? We refrigerate leftovers promptly because warm food gives bacteria a chance to multiply fast! The temperature range where they grow best is called the danger zone, so leftovers sho https://socialmedia.xdme.com/tony/videos-book9/page-117.mp4 https://www.youtube.com/embed/a6nGX6UJTLs 120 2026-10-02T22:34:18+00:00 yes https://xdme.com/watch-book9-q118.html https://xdme.com/book9-thumbs/page-118.jpg Why Compost Food Scraps? We compost food scraps to turn peels and leftovers into healthy soil! In a landfill, scraps get buried and rot without air, and can make a gas called methane that warms the planet. https://socialmedia.xdme.com/tony/videos-book9/page-118.mp4 https://www.youtube.com/embed/I5UGw7Gb7H4 117 2026-10-02T22:37:21+00:00 yes https://xdme.com/watch-book9-q119.html https://xdme.com/book9-thumbs/page-119.jpg Why Do Farmers Markets Feel Different From Megastores? Farmers markets feel different from megastores because you meet the people who grow your food! The food usually travels a shorter distance, and the selection follows the seasons. Y https://socialmedia.xdme.com/tony/videos-book9/page-119.mp4 https://www.youtube.com/embed/ryAThK7V_aE 112 2026-10-02T22:39:53+00:00 yes https://xdme.com/watch-book9-q120.html https://xdme.com/book9-thumbs/page-120.jpg Why Is Food Waste a Big Deal? Food waste is a big deal because wasted food also wastes the water, land, and energy used to grow it! At the same time, many people still face hunger. Smart planning and saving lef https://socialmedia.xdme.com/tony/videos-book9/page-120.mp4 https://www.youtube.com/embed/tfJl0M8C_oU 115 2026-10-02T22:42:27+00:00 yes https://xdme.com/watch-book9-q121.html https://xdme.com/book9-thumbs/page-121.jpg Why Do Nutrition Labels List Serving Sizes? Nutrition labels list serving sizes so you can compare foods fairly and estimate what you eat! All the numbers on the label are for one serving, not for the whole package. The math https://socialmedia.xdme.com/tony/videos-book9/page-121.mp4 https://www.youtube.com/embed/hzNHNhhCrpA 112 2026-10-02T22:45:30+00:00 yes https://xdme.com/watch-book9-q122.html https://xdme.com/book9-thumbs/page-122.jpg Why Wash Produce Even If You’ll Peel It? We wash produce even if we will peel it because the knife can carry dirt and germs from the skin into the part we eat! Peels touch soil, hands, boxes, and shelves. A simple rinse i https://socialmedia.xdme.com/tony/videos-book9/page-122.mp4 https://www.youtube.com/embed/1rDUyBoYGMg 113 2026-10-02T22:48:03+00:00 yes https://xdme.com/watch-book9-q123.html https://xdme.com/book9-thumbs/page-123.jpg Why Do Some Fish Need Cold Trucks More than Apples? Fish need colder trucks than apples because seafood spoils much faster! Fish are rich in moist protein, and they can grow harmful bacteria quickly if warm. Apples have tough skins https://socialmedia.xdme.com/tony/videos-book9/page-123.mp4 https://www.youtube.com/embed/CfFdj1DskeE 116 2026-10-02T22:50:35+00:00 yes https://xdme.com/watch-book9-q124.html https://xdme.com/book9-thumbs/page-124.jpg Why Celebrate Cultural Foods? We celebrate cultural foods because recipes carry history, geography, and family love! A traditional dish can tell you where people lived, what grew there, and what they cared abou https://socialmedia.xdme.com/tony/videos-book9/page-124.mp4 https://www.youtube.com/embed/z23hifCgv2o 115 2026-10-02T22:53:40+00:00 yes https://xdme.com/watch-book9-q125.html https://xdme.com/book9-thumbs/page-125.jpg Why Say Thanks Along the Food Chain? We say thanks along the food chain because many hands help get dinner to your plate! From soil microbes and farmers to truck drivers, grocers, and cooks, lots of people and living https://socialmedia.xdme.com/tony/videos-book9/page-125.mp4 https://www.youtube.com/embed/RTrIysNoI9k 112 2026-10-02T22:56:42+00:00 yes https://xdme.com/watch-book9-q126.html https://xdme.com/book9-thumbs/page-126.jpg Why Wash Hands Again After Touching Raw Eggs or Meat? We wash our hands again after touching raw eggs or meat because they can carry germs that hands spread to everything else! Germs like Salmonella can hide on raw eggs and raw meat. https://socialmedia.xdme.com/tony/videos-book9/page-126.mp4 https://www.youtube.com/embed/9l6-NJv2ZaI 116 2026-10-02T22:59:15+00:00 yes https://xdme.com/watch-book9-q127.html https://xdme.com/book9-thumbs/page-127.jpg Why Use Separate Boards for Raw Meat and Veggies? We use separate cutting boards for raw meat and veggies so germs from the meat do not land on foods we will not cook! Raw meat juices can carry germs, and they drip and spread. Sep https://socialmedia.xdme.com/tony/videos-book9/page-127.mp4 https://www.youtube.com/embed/YuLK1ZN6vRY 114 2026-10-02T23:02:18+00:00 yes https://xdme.com/watch-book9-q128.html https://xdme.com/book9-thumbs/page-128.jpg Why Cook Burgers to a Safe Temperature? We cook burgers to a safe temperature because germs can hide inside ground meat! When meat is ground up, germs from the surface get mixed all the way through. A food thermometer is https://socialmedia.xdme.com/tony/videos-book9/page-128.mp4 https://www.youtube.com/embed/UkRYkHjPZ5s 116 2026-10-02T23:05:20+00:00 yes https://xdme.com/watch-book9-q129.html https://xdme.com/book9-thumbs/page-129.jpg Why Thaw Meat in the Fridge, Not on the Counter? We thaw meat in the fridge, not on the counter, to keep bacteria from growing while it warms up! On a counter, the outside gets warm while the center stays frozen. That warm outsid https://socialmedia.xdme.com/tony/videos-book9/page-129.mp4 https://www.youtube.com/embed/_eAgw4I8NrI 110 2026-10-02T23:07:53+00:00 yes https://xdme.com/watch-book9-q130.html https://xdme.com/book9-thumbs/page-130.jpg Why Isn’t a Sniff Test Enough to Tell If Food Is Safe? A sniff test is not enough because some dangerous bacteria do not smell bad! The germs that make food stinky are often different from the ones that make people sick. So dates, stor https://socialmedia.xdme.com/tony/videos-book9/page-130.mp4 https://www.youtube.com/embed/Of9KpCtZAHs 110 2026-10-02T23:10:59+00:00 yes https://xdme.com/watch-book9-q131.html https://xdme.com/book9-thumbs/page-131.jpg Why Keep the Fridge at About 4°C (40°F)? We keep the fridge at about 4 degrees Celsius, or 40 degrees Fahrenheit, because that cold slows most spoilage and harmful germs! A fridge thermometer is better than guessing, beca https://socialmedia.xdme.com/tony/videos-book9/page-131.mp4 https://www.youtube.com/embed/VJGBpAqZcn4 119 2026-10-02T23:14:01+00:00 yes https://xdme.com/watch-book9-q132.html https://xdme.com/book9-thumbs/page-132.jpg Why Should We Throw Out Jars with Bulging Lids? We throw out jars with bulging lids because a bulge can mean microbes inside are making gas! That is a warning sign that the food may be unsafe. Never taste a suspicious jar or can https://socialmedia.xdme.com/tony/videos-book9/page-132.mp4 https://www.youtube.com/embed/ddfZWov3B4Q 110 2026-10-02T23:16:33+00:00 yes https://xdme.com/watch-book9-q133.html https://xdme.com/book9-thumbs/page-133.jpg Why Tie Hair Back in the Kitchen? We tie hair back in the kitchen so it stays out of the food and away from heat! Loose hair can fall into a meal or swing near flames and hot burners. Tying it back keeps food clean https://socialmedia.xdme.com/tony/videos-book9/page-133.mp4 https://www.youtube.com/embed/MEVYWpr7RkI 105 2026-10-02T23:19:20+00:00 yes https://xdme.com/watch-book9-q134.html https://xdme.com/book9-thumbs/page-134.jpg Why Wipe Spills Right Away? We wipe spills right away because they can make people slip and they can grow germs! A wet floor is slippery, and a sticky counter feeds microbes and invites pests. Quick cleanups https://socialmedia.xdme.com/tony/videos-book9/page-134.mp4 https://www.youtube.com/embed/H6Dmg54Syyw 115 2026-10-02T23:21:54+00:00 yes https://xdme.com/watch-book9-q135.html https://xdme.com/book9-thumbs/page-135.jpg Why Read Recipe Steps Fully First? We read recipe steps fully first so there are no surprises in the middle of cooking! A surprise can mean burnt pans or missing ingredients. Detectives preview the whole plan before https://socialmedia.xdme.com/tony/videos-book9/page-135.mp4 https://www.youtube.com/embed/2Ihbve7P38s 110 2026-10-02T23:24:59+00:00 yes https://xdme.com/watch-book9-q136.html https://xdme.com/book9-thumbs/page-136.jpg Why Measure with the Right Tools? We measure with the right tools because cooking is chemistry, and accurate amounts make recipes work! Liquid cups and dry cups are built differently. And a spoon from the drawer is https://socialmedia.xdme.com/tony/videos-book9/page-136.mp4 https://www.youtube.com/embed/bWKj76vH6Dg 114 2026-10-02T23:27:42+00:00 yes https://xdme.com/watch-book9-q137.html https://xdme.com/book9-thumbs/page-137.jpg Why Taste with a Clean Spoon Each Time? We taste with a clean spoon each time because double-dipping puts mouth microbes back into the pot! Everyone has bacteria in their mouth. A fresh spoon keeps the food friendlier fo https://socialmedia.xdme.com/tony/videos-book9/page-137.mp4 https://www.youtube.com/embed/V4OAG1Irq9w 109 2026-10-02T23:30:15+00:00 yes https://xdme.com/watch-book9-q138.html https://xdme.com/book9-thumbs/page-138.jpg Why Be Careful with Raw Cookie Dough? We are careful with raw cookie dough because raw flour and raw eggs can carry germs! Baking kills these germs when the cookies are cooked all the way through, so ask a grown-up bef https://socialmedia.xdme.com/tony/videos-book9/page-138.mp4 https://www.youtube.com/embed/P_k0ENMaeZE 112 2026-10-02T23:32:49+00:00 yes https://xdme.com/watch-book9-q139.html https://xdme.com/book9-thumbs/page-139.jpg Why Store Cleaning Sprays Away From Food? We store cleaning sprays away from food because chemicals are not ingredients! Keeping them apart prevents mix-ups that could poison a meal. It also keeps spray from landing on foo https://socialmedia.xdme.com/tony/videos-book9/page-139.mp4 https://www.youtube.com/embed/Ot2K_qLnU64 113 2026-10-02T23:35:51+00:00 yes https://xdme.com/watch-book9-q140.html https://xdme.com/book9-thumbs/page-140.jpg Why Use Oven Mitts with No Wet Spots? We use dry oven mitts because wet fabric carries heat to your skin much faster! Water conducts heat well, and hot water in a mitt can turn to steam. Dry, thick mitts block heat muc https://socialmedia.xdme.com/tony/videos-book9/page-140.mp4 https://www.youtube.com/embed/Kgu9kbgW5c8 107 2026-10-02T23:38:25+00:00 yes https://xdme.com/watch-book9-q141.html https://xdme.com/book9-thumbs/page-141.jpg Why Are Some Foods Choking Hazards? Some foods are choking hazards because they are round, hard, or sticky and can block a small airway! Whole grapes, nuts, and hard candy are examples, and grown-ups cut up foods for https://socialmedia.xdme.com/tony/videos-book9/page-141.mp4 https://www.youtube.com/embed/FQMwJ2a82-8 114 2026-10-02T23:40:58+00:00 yes https://xdme.com/watch-book9-q142.html https://xdme.com/book9-thumbs/page-142.jpg Why Does Raw Meat Go on the Bottom Shelf of the Fridge? Raw meat goes on the bottom shelf of the fridge so its juices cannot drip onto other foods! Raw juices can carry germs, and a leak can spread them across the fridge. On the bottom https://socialmedia.xdme.com/tony/videos-book9/page-142.mp4 https://www.youtube.com/embed/NnD7Xh7VJPU 115 2026-10-02T23:44:02+00:00 yes https://xdme.com/watch-book9-q143.html https://xdme.com/book9-thumbs/page-143.jpg Why Keep Pets Off Kitchen Counters? We keep pets off kitchen counters because paws and fur can carry germs from the floor to where food is prepared! Pets walk through litter boxes, yards, and dirt, and they lick thei https://socialmedia.xdme.com/tony/videos-book9/page-143.mp4 https://www.youtube.com/embed/-5PloSklY4U 113 2026-10-02T23:46:40+00:00 yes https://xdme.com/watch-book9-q144.html https://xdme.com/book9-thumbs/page-144.jpg Why Cool Big Soups in Shallow Pans? We cool big soups in shallow pans because deep pots stay warm in the middle for far too long! A slow-cooling soup spends hours in the bacteria danger zone. Shallow layers chill fas https://socialmedia.xdme.com/tony/videos-book9/page-144.mp4 https://www.youtube.com/embed/k__m8CpkG_c 114 2026-10-02T23:50:16+00:00 yes https://xdme.com/watch-book9-q145.html https://xdme.com/book9-thumbs/page-145.jpg Why Check for Food Recalls? We check for food recalls because sometimes problems are found after food is already packed and sold! A recall notice tells families which products to stop using. It is a public sa https://socialmedia.xdme.com/tony/videos-book9/page-145.mp4 https://www.youtube.com/embed/xlvYjvycqms 116 2026-10-02T23:53:48+00:00 yes https://xdme.com/watch-book9-q146.html https://xdme.com/book9-thumbs/page-146.jpg Why Adapt Recipes for Allergies Politely? We adapt recipes for allergies politely so friends stay safe and included! A food allergy means the body treats a harmless food as a danger, and even a small amount can make someon https://socialmedia.xdme.com/tony/videos-book9/page-146.mp4 https://www.youtube.com/embed/7UrO0t0KspQ 116 2026-10-02T23:56:22+00:00 yes https://xdme.com/watch-book9-q147.html https://xdme.com/book9-thumbs/page-147.jpg Why Should You Get Out and Tell a Grown-Up If a Fire Starts in the Kitchen? If a fire starts in the kitchen, the safest plan is to get out, tell a grown-up, and call for help! You are never supposed to fight a fire yourself. Grown-ups and firefighters have https://socialmedia.xdme.com/tony/videos-book9/page-147.mp4 https://www.youtube.com/embed/vofD75t2p3Y 119 2026-10-02T23:59:24+00:00 yes https://xdme.com/watch-book9-q148.html https://xdme.com/book9-thumbs/page-148.jpg Why Should You Change Only One Thing at a Time When You Tweak a Recipe? We change only one thing at a time when we tweak a recipe so we know what caused the result! Changing one thing and writing it down lets you repeat winners and fix flops. That is t https://socialmedia.xdme.com/tony/videos-book9/page-148.mp4 https://www.youtube.com/embed/3UdkhXlo4IU 109 2026-10-03T00:01:57+00:00 yes https://xdme.com/watch-book9-q149.html https://xdme.com/book9-thumbs/page-149.jpg Why Teach Younger Siblings Kitchen Rules? We teach younger siblings kitchen rules because passing on safety habits multiplies safety! Handwashing, knife boundaries, and allergy checks keep everyone safer, especially little https://socialmedia.xdme.com/tony/videos-book9/page-149.mp4 https://www.youtube.com/embed/KXXOHXULs8g 119 2026-10-03T00:05:07+00:00 yes https://xdme.com/watch-book9-q150.html https://xdme.com/book9-thumbs/page-150.jpg Why Is a Kitchen the Best Science Lab You Already Own? A kitchen is the best science lab you already own because every meal is full of science! There is heat, mixing, and tiny microbes at work, plus tools like thermometers and scales. https://socialmedia.xdme.com/tony/videos-book9/page-150.mp4 https://www.youtube.com/embed/2pvJlj-BGfE 116 2026-10-03T00:07:51+00:00 yes https://xdme.com/watch-book10-q001.html https://xdme.com/book10-thumbs/page-001.jpg Why Does Your Body Need a Skeleton? Your body needs a skeleton because bones are like the strong frame inside a building! Bones hold you up, protect the soft parts inside, and even make new blood cells. A skeleton is https://socialmedia.xdme.com/tony/videos-book10/page-001.mp4 https://www.youtube.com/embed/kf56KswoP14 118 2026-10-03T01:12:38+00:00 yes https://xdme.com/watch-book10-q002.html https://xdme.com/book10-thumbs/page-002.jpg Why Do Babies Have More Bones than Adults? Babies have more bones than adults because many of a baby's bones start out as separate little pieces! As you grow, some of those pieces join together into bigger, stronger bones. https://socialmedia.xdme.com/tony/videos-book10/page-002.mp4 https://www.youtube.com/embed/JXTo0JGq4EI 115 2026-10-03T01:12:40+00:00 yes https://xdme.com/watch-book10-q003.html https://xdme.com/book10-thumbs/page-003.jpg Why Is Cartilage in Your Nose and Ears? Your nose and ears have cartilage because they need support that is strong but bendy! Cartilage is firm enough to hold a shape, and flexible enough to bend without breaking. Not al https://socialmedia.xdme.com/tony/videos-book10/page-003.mp4 https://www.youtube.com/embed/YpkuuwYHcsg 112 2026-10-03T01:12:41+00:00 yes https://xdme.com/watch-book10-q004.html https://xdme.com/book10-thumbs/page-004.jpg Why Do Joints Let You Bend? Joints let you bend because they are the meeting places where two bones come together! The bones are not stuck. They glide and swing in special shapes. https://socialmedia.xdme.com/tony/videos-book10/page-004.mp4 https://www.youtube.com/embed/e1qcjdhS0Z4 112 2026-10-03T01:12:50+00:00 yes https://xdme.com/watch-book10-q005.html https://xdme.com/book10-thumbs/page-005.jpg Why Does Cracking Knuckles Make Noise? Knuckles can make a popping noise because of tiny gas bubbles in the fluid inside your joints! When a joint stretches, a bubble can pop, and you hear a little crack. It is a gas po https://socialmedia.xdme.com/tony/videos-book10/page-005.mp4 https://www.youtube.com/embed/aQk4dKLRl5I 111 2026-10-03T01:12:58+00:00 yes https://xdme.com/watch-book10-q006.html https://xdme.com/book10-thumbs/page-006.jpg Why Do Muscles Pull But Not Push? Muscles pull but never push because muscle fibers can only get shorter and tighter! They squeeze to pull on your bones. To move in the other direction, a different muscle does the https://socialmedia.xdme.com/tony/videos-book10/page-006.mp4 https://www.youtube.com/embed/O_KARXmGC2w 108 2026-10-03T01:13:00+00:00 yes https://xdme.com/watch-book10-q007.html https://xdme.com/book10-thumbs/page-007.jpg Why Do Goosebumps Pop Up When You Are Cold or Scared? Goosebumps pop up because tiny muscles pull your hairs upright when you are cold, scared, or amazed! It is a quick reflex, which means your body does it without you deciding. It is https://socialmedia.xdme.com/tony/videos-book10/page-007.mp4 https://www.youtube.com/embed/uRvYRgQo0Qk 112 2026-10-03T01:13:01+00:00 yes https://xdme.com/watch-book10-q008.html https://xdme.com/book10-thumbs/page-008.jpg Why Warm Up Before Sports? We warm up before sports to get our muscles ready for action! Gentle movement gets more blood flowing to your muscles and loosens them up. Then sudden sprints and jumps are kinder https://socialmedia.xdme.com/tony/videos-book10/page-008.mp4 https://www.youtube.com/embed/3aoo267uzlE 108 2026-10-03T01:13:02+00:00 yes https://xdme.com/watch-book10-q009.html https://xdme.com/book10-thumbs/page-009.jpg Why Do Tendons Connect Muscle to Bone? Tendons connect muscle to bone because a muscle needs a strong cable to pull on the skeleton! Without tendons, a muscle's squeeze would not move your bones at all. A tendon works l https://socialmedia.xdme.com/tony/videos-book10/page-009.mp4 https://www.youtube.com/embed/SPgHD1aghe4 106 2026-10-03T01:13:03+00:00 yes https://xdme.com/watch-book10-q010.html https://xdme.com/book10-thumbs/page-010.jpg Why Do Ligaments Connect Bone to Bone? Ligaments connect bone to bone so your joints stay steady and in place! They are strong straps that stop bones from wandering off during jumps and twists. A ligament is like a seat https://socialmedia.xdme.com/tony/videos-book10/page-010.mp4 https://www.youtube.com/embed/nTg0ELRiMjw 112 2026-10-03T01:13:04+00:00 yes https://xdme.com/watch-book10-q011.html https://xdme.com/book10-thumbs/page-011.jpg Why Do Some Kids Get Grow Pains? Some kids get achy legs at night when their bodies are growing, and people call these grow pains! They are common, and doctors say they are usually harmless. If a pain is strong, s https://socialmedia.xdme.com/tony/videos-book10/page-011.mp4 https://www.youtube.com/embed/2jKdEGKZCm4 111 2026-10-03T01:13:06+00:00 yes https://xdme.com/watch-book10-q012.html https://xdme.com/book10-thumbs/page-012.jpg Why Is Posture Helpful? Good posture is helpful because it lines up your bones so your muscles do not have to work so hard! When your bones are stacked well, your body saves energy. Slouching can make som https://socialmedia.xdme.com/tony/videos-book10/page-012.mp4 https://www.youtube.com/embed/2Zq5mtUxshM 108 2026-10-03T01:13:08+00:00 yes https://xdme.com/watch-book10-q013.html https://xdme.com/book10-thumbs/page-013.jpg Why Do Backpacks Need Two Straps? Backpacks need two straps so the weight is shared across both sides of your body! That keeps your spine from being pulled sideways. A pack should also be light, so pack only what y https://socialmedia.xdme.com/tony/videos-book10/page-013.mp4 https://www.youtube.com/embed/tIkxu58bDzY 106 2026-10-03T01:13:09+00:00 yes https://xdme.com/watch-book10-q014.html https://xdme.com/book10-thumbs/page-014.jpg Why Do Bones Heal After Breaks? Broken bones can heal because bone is a living material that repairs itself! Special bone cells follow a repair plan, step by step. A cast helps keep the pieces lined up while the https://socialmedia.xdme.com/tony/videos-book10/page-014.mp4 https://www.youtube.com/embed/Fg6uUBX-pJo 111 2026-10-03T01:13:15+00:00 yes https://xdme.com/watch-book10-q015.html https://xdme.com/book10-thumbs/page-015.jpg Why Is Calcium Famous for Bones? Calcium is famous for bones because it is one of the main minerals that make bones hard! Think of calcium and other minerals as the concrete in your bones. Your body needs help fro https://socialmedia.xdme.com/tony/videos-book10/page-015.mp4 https://www.youtube.com/embed/MbvT44op4H0 116 2026-10-03T01:13:17+00:00 yes https://xdme.com/watch-book10-q016.html https://xdme.com/book10-thumbs/page-016.jpg Why Do You Get Taller in Spurts? You get taller in spurts because your long bones grow in bursts, not at a steady speed! Growth plates at the ends of your bones add length. Sometimes they work fast, and sometimes https://socialmedia.xdme.com/tony/videos-book10/page-016.mp4 https://www.youtube.com/embed/X1ucFd2q8jY 110 2026-10-03T01:13:18+00:00 yes https://xdme.com/watch-book10-q017.html https://xdme.com/book10-thumbs/page-017.jpg Why Do Fingers Get Wrinkly in Long Baths? Fingers get wrinkly in long baths because your nervous system tightens tiny blood vessels in your fingertips! That makes the skin pucker up into ridges. Scientists think the wrinkl https://socialmedia.xdme.com/tony/videos-book10/page-017.mp4 https://www.youtube.com/embed/Loe1UZbwPaA 116 2026-10-03T01:14:42+00:00 yes https://xdme.com/watch-book10-q018.html https://xdme.com/book10-thumbs/page-018.jpg Why Is Core Strength About More than Abs? Core strength is about more than abs because your core is a whole belt of muscles around your middle! These deep muscles steady your spine for balance and safe lifting. Your core i https://socialmedia.xdme.com/tony/videos-book10/page-018.mp4 https://www.youtube.com/embed/28BgdjCYRuw 111 2026-10-03T01:16:45+00:00 yes https://xdme.com/watch-book10-q019.html https://xdme.com/book10-thumbs/page-019.jpg Why Do Dancers Build Strong Feet? Dancers build strong feet because their feet do so many small, careful jobs! Small muscles and tendons in your feet make tiny adjustments all the time. With practice, those muscles https://socialmedia.xdme.com/tony/videos-book10/page-019.mp4 https://www.youtube.com/embed/Qz2r1bmSwZU 111 2026-10-03T01:19:48+00:00 yes https://xdme.com/watch-book10-q020.html https://xdme.com/book10-thumbs/page-020.jpg Why Stretch After Exercise? Gentle stretching after exercise can feel good and helps you stay flexible as your muscles cool down! Flexibility is part of training, too. Just stretch slowly, and never bounce ha https://socialmedia.xdme.com/tony/videos-book10/page-020.mp4 https://www.youtube.com/embed/15KIlgDDoY8 112 2026-10-03T01:22:21+00:00 yes https://xdme.com/watch-book10-q021.html https://xdme.com/book10-thumbs/page-021.jpg Why Do Calluses Form? Calluses form because your skin builds a thicker layer where something rubs it again and again! The extra skin acts like a natural glove patch. It protects the softer skin undernea https://socialmedia.xdme.com/tony/videos-book10/page-021.mp4 https://www.youtube.com/embed/7gdKs5A7e0c 113 2026-10-03T01:24:54+00:00 yes https://xdme.com/watch-book10-q022.html https://xdme.com/book10-thumbs/page-022.jpg Why Is Rest Part of Getting Stronger? Rest is part of getting stronger because your muscles repair and grow stronger between workouts! The hard work is the signal, and rest is when the building happens. Nonstop strain https://socialmedia.xdme.com/tony/videos-book10/page-022.mp4 https://www.youtube.com/embed/_ZvLGJoyfPA 107 2026-10-03T01:27:27+00:00 yes https://xdme.com/watch-book10-q023.html https://xdme.com/book10-thumbs/page-023.jpg Why Do Sneakers Cushion Landings? Sneakers cushion landings because they spread out the force when your foot hits the ground! That makes the hit gentler on your ankles, knees, and hips. Worn-out shoes cushion less. https://socialmedia.xdme.com/tony/videos-book10/page-023.mp4 https://www.youtube.com/embed/OKDmbtq7ujc 110 2026-10-03T01:30:30+00:00 yes https://xdme.com/watch-book10-q024.html https://xdme.com/book10-thumbs/page-024.jpg Why Practice Balance? Practicing balance trains the sensors in your ears, eyes, and muscles to work as a team! Better balance means fewer tumbles. Balance is a skill you can practice, not a talent switc https://socialmedia.xdme.com/tony/videos-book10/page-024.mp4 https://www.youtube.com/embed/voQnZWBCzB0 109 2026-10-03T01:33:04+00:00 yes https://xdme.com/watch-book10-q025.html https://xdme.com/book10-thumbs/page-025.jpg Why Move Every Day? You should move every day because movement is good for your bones, your heart, your mood, and even your brain! Active play makes your whole body work better. Health experts suggest https://socialmedia.xdme.com/tony/videos-book10/page-025.mp4 https://www.youtube.com/embed/gbR7pBd7j7s 117 2026-10-03T01:36:07+00:00 yes https://xdme.com/watch-book10-q026.html https://xdme.com/book10-thumbs/page-026.jpg Why Does Your Heart Beat All By Itself? Your heart beats all by itself because it has its own tiny electrical starter! A small group of cells makes signals that tell the heart to squeeze. So it keeps going without you th https://socialmedia.xdme.com/tony/videos-book10/page-026.mp4 https://www.youtube.com/embed/Ajm9zOU4mg8 111 2026-10-03T01:38:39+00:00 yes https://xdme.com/watch-book10-q027.html https://xdme.com/book10-thumbs/page-027.jpg Why Can a Stethoscope Let You Hear a Heartbeat? A stethoscope lets you hear a heartbeat because it carries sound from your chest right to a doctor's ears! Heart sounds are quiet, so the tubes help guide them. Doctors listen for https://socialmedia.xdme.com/tony/videos-book10/page-027.mp4 https://www.youtube.com/embed/2B-hlVQazm4 111 2026-10-03T01:41:14+00:00 yes https://xdme.com/watch-book10-q028.html https://xdme.com/book10-thumbs/page-028.jpg Why Does Heart Rate Rise When You Sprint? Your heart rate rises when you sprint because your muscles need more oxygen and fuel, fast! Your heart speeds up to make deliveries. It also picks up the trash, which is carbon dio https://socialmedia.xdme.com/tony/videos-book10/page-028.mp4 https://www.youtube.com/embed/JPe5pVjBfRc 112 2026-10-03T01:44:18+00:00 yes https://xdme.com/watch-book10-q029.html https://xdme.com/book10-thumbs/page-029.jpg Why Does Your Face Turn Red When You Run or Feel Embarrassed? Your face turns red when you run or feel embarrassed because tiny blood vessels near your skin get wider! More blood flows close to the surface, so your face looks warm and rosy. I https://socialmedia.xdme.com/tony/videos-book10/page-029.mp4 https://www.youtube.com/embed/OzBB6VbwhKk 109 2026-10-03T01:46:50+00:00 yes https://xdme.com/watch-book10-q030.html https://xdme.com/book10-thumbs/page-030.jpg Why Do You Have Different Blood Types? People have different blood types because the surface of red blood cells can wear different tiny markers! The main types are called A, B, AB, and O, plus a marker called Rh. Matchi https://socialmedia.xdme.com/tony/videos-book10/page-030.mp4 https://www.youtube.com/embed/bRswa9gpfTU 112 2026-10-03T01:49:23+00:00 yes https://xdme.com/watch-book10-q031.html https://xdme.com/book10-thumbs/page-031.jpg Why Do Veins Look Blueish Under Skin? Veins look bluish under your skin, but the blood inside them is always red! Your skin filters light, so veins look blue or green. It is a trick of light, not blue blood. https://socialmedia.xdme.com/tony/videos-book10/page-031.mp4 https://www.youtube.com/embed/BtnBATLj-2c 114 2026-10-03T01:52:25+00:00 yes https://xdme.com/watch-book10-q032.html https://xdme.com/book10-thumbs/page-032.jpg Why Do You Need Lungs? You need lungs because they trade gases with the air! Oxygen goes in, and carbon dioxide comes out. This happens across tiny, moist air sacs called alveoli. https://socialmedia.xdme.com/tony/videos-book10/page-032.mp4 https://www.youtube.com/embed/s7l3ngVCi9E 111 2026-10-03T01:54:58+00:00 yes https://xdme.com/watch-book10-q033.html https://xdme.com/book10-thumbs/page-033.jpg Why Are There So Many Alveoli? You have so many alveoli because a huge surface area lets lots of oxygen cross into your blood quickly! It is like having many windows instead of just one. More windows means more https://socialmedia.xdme.com/tony/videos-book10/page-033.mp4 https://www.youtube.com/embed/7BZXhIcJEPI 114 2026-10-03T01:58:02+00:00 yes https://xdme.com/watch-book10-q034.html https://xdme.com/book10-thumbs/page-034.jpg Why Is Yawning Contagious? Yawns can be contagious because seeing or hearing someone yawn can make you yawn too! Scientists think it may be linked to empathy and social bonding. But they are still studying i https://socialmedia.xdme.com/tony/videos-book10/page-034.mp4 https://www.youtube.com/embed/A3NlUXHkOek 107 2026-10-03T02:00:33+00:00 yes https://xdme.com/watch-book10-q035.html https://xdme.com/book10-thumbs/page-035.jpg Why Do You Cough When Something Goes Down the Wrong Way? You cough when something goes down the wrong way because a cough is a quick blast of air that pushes things out! It clears food or drink from your windpipe and protects your lungs. https://socialmedia.xdme.com/tony/videos-book10/page-035.mp4 https://www.youtube.com/embed/N7TjKE1kEjg 109 2026-10-03T02:03:07+00:00 yes https://xdme.com/watch-book10-q036.html https://xdme.com/book10-thumbs/page-036.jpg Why Does Exercise Make You Breathe Harder? Exercise makes you breathe harder because your working muscles need more oxygen and make more carbon dioxide! Sensors tell your brain to speed up and deepen your breathing. That br https://socialmedia.xdme.com/tony/videos-book10/page-036.mp4 https://www.youtube.com/embed/GjpJpUJpdIc 115 2026-10-03T02:06:11+00:00 yes https://xdme.com/watch-book10-q037.html https://xdme.com/book10-thumbs/page-037.jpg Why Is Nose Breathing Often Helpful at Rest? Nose breathing is often helpful at rest because your nose cleans, warms, and moistens the air before it reaches your lungs! It is like a built-in air conditioner and filter. Your m https://socialmedia.xdme.com/tony/videos-book10/page-037.mp4 https://www.youtube.com/embed/LwIASZGkcn4 111 2026-10-03T02:08:43+00:00 yes https://xdme.com/watch-book10-q038.html https://xdme.com/book10-thumbs/page-038.jpg Why Does a Stuffy Nose Change Your Voice? A stuffy nose changes your voice because blocked nasal spaces change resonance, the echo chambers of speech! Your sound bounces around inside your head and nose. When the spaces fi https://socialmedia.xdme.com/tony/videos-book10/page-038.mp4 https://www.youtube.com/embed/5aScTl6HrzA 111 2026-10-03T02:11:26+00:00 yes https://xdme.com/watch-book10-q039.html https://xdme.com/book10-thumbs/page-039.jpg Why Do You Need Iron in Food? You need iron in food because iron helps your blood carry oxygen! Iron is part of hemoglobin, the red substance in your red blood cells. Foods like beans, meat, and leafy greens ha https://socialmedia.xdme.com/tony/videos-book10/page-039.mp4 https://www.youtube.com/embed/QWTp8jRrzns 113 2026-10-03T02:14:00+00:00 yes https://xdme.com/watch-book10-q040.html https://xdme.com/book10-thumbs/page-040.jpg Why Do Cuts Stop Bleeding with Clots? Cuts stop bleeding because your blood can make a plug called a clot! Tiny helpers in your blood rush to the spot and build it. Then a scab shields the area while repair crews work https://socialmedia.xdme.com/tony/videos-book10/page-040.mp4 https://www.youtube.com/embed/vy9v-Zm9pt8 110 2026-10-03T02:16:33+00:00 yes https://xdme.com/watch-book10-q041.html https://xdme.com/book10-thumbs/page-041.jpg Why Measure Blood Pressure? Doctors measure blood pressure because it shows how hard your blood pushes on the walls of your arteries! Your heart squeezes, and the blood presses outward on the vessel walls. Do https://socialmedia.xdme.com/tony/videos-book10/page-041.mp4 https://www.youtube.com/embed/AMzuzUoAIJw 116 2026-10-03T02:19:36+00:00 yes https://xdme.com/watch-book10-q042.html https://xdme.com/book10-thumbs/page-042.jpg Why Are Arteries Thicker-Walled than Veins? Arteries have thicker walls than veins because they take high-pressure spurts of blood straight from your heart! Veins carry blood back at lower pressure. Each tube is built for it https://socialmedia.xdme.com/tony/videos-book10/page-042.mp4 https://www.youtube.com/embed/9Tfht6kQ0uw 114 2026-10-03T02:22:07+00:00 yes https://xdme.com/watch-book10-q043.html https://xdme.com/book10-thumbs/page-043.jpg Why Does Laughing Feel Good in Your Chest? Laughing feels good in your chest because it changes your breathing, your muscles, and even the chemicals in your brain! It is a full-body giggle workout. Laughter is also a way pe https://socialmedia.xdme.com/tony/videos-book10/page-043.mp4 https://www.youtube.com/embed/mQrGBVzmTQI 113 2026-10-03T02:24:40+00:00 yes https://xdme.com/watch-book10-q044.html https://xdme.com/book10-thumbs/page-044.jpg Why Can’t You Hold Your Breath Forever? You cannot hold your breath forever because your body has a built-in alarm that says breathe! Rising carbon dioxide in your blood alerts your brain loudly. That urge protects you f https://socialmedia.xdme.com/tony/videos-book10/page-044.mp4 https://www.youtube.com/embed/2SRg7ingX00 111 2026-10-03T02:27:13+00:00 yes https://xdme.com/watch-book10-q045.html https://xdme.com/book10-thumbs/page-045.jpg Why Do Inhalers Help Some Kids with Asthma? Inhalers help some kids with asthma because the medicine can open up tightened airways so air flows more easily! Asthma plans are personal, and a doctor or nurse decides what is ri https://socialmedia.xdme.com/tony/videos-book10/page-045.mp4 https://www.youtube.com/embed/WQiyE0KXGFg 116 2026-10-03T02:30:16+00:00 yes https://xdme.com/watch-book10-q046.html https://xdme.com/book10-thumbs/page-046.jpg Why Do People Take CPR Classes? People take CPR classes to learn hands-on skills that can help keep blood and air moving until help arrives! CPR stands for cardiopulmonary resuscitation. In an emergency, tell a g https://socialmedia.xdme.com/tony/videos-book10/page-046.mp4 https://www.youtube.com/embed/FoaG4M2G6Co 122 2026-10-03T02:32:48+00:00 yes https://xdme.com/watch-book10-q047.html https://xdme.com/book10-thumbs/page-047.jpg Why Does Altitude Make Some People Breathless? High mountains can make some people breathless because the air is thinner there! Thinner air has less oxygen in each breath. Bodies slowly adjust over days, and anyone who feels un https://socialmedia.xdme.com/tony/videos-book10/page-047.mp4 https://www.youtube.com/embed/umA4MpVqNpo 112 2026-10-03T02:35:51+00:00 yes https://xdme.com/watch-book10-q048.html https://xdme.com/book10-thumbs/page-048.jpg Why Does Blood Have a Liquid Part Called Plasma? Blood has a liquid part called plasma that carries things around your body! Plasma is the pale yellow liquid that makes up more than half of your blood. It carries blood cells, nut https://socialmedia.xdme.com/tony/videos-book10/page-048.mp4 https://www.youtube.com/embed/sR8CQDh6lq8 111 2026-10-03T02:38:25+00:00 yes https://xdme.com/watch-book10-q049.html https://xdme.com/book10-thumbs/page-049.jpg Why Warm Up Cold Fingers By Moving? Moving warms up cold fingers because muscle activity and changes in your blood vessels bring warmer blood to your hands! Motion spreads heat around your body. That is why jumping j https://socialmedia.xdme.com/tony/videos-book10/page-049.mp4 https://www.youtube.com/embed/LkGRg1e5AXI 113 2026-10-03T02:41:04+00:00 yes https://xdme.com/watch-book10-q050.html https://xdme.com/book10-thumbs/page-050.jpg Why Thank Your Heart Today? You can thank your heart today because it works hard every second, without ever asking for a break! It beats about 100,000 times a day. Sleep, play, good food, and kindness all hel https://socialmedia.xdme.com/tony/videos-book10/page-050.mp4 https://www.youtube.com/embed/JTXGrWIV7Gs 110 2026-10-03T02:44:08+00:00 yes https://xdme.com/watch-book10-q051.html https://xdme.com/book10-thumbs/page-051.jpg Why Is the Brain the Boss? Your brain is the boss because it reads your senses, plans your moves, stores your memories, and runs automatic jobs! Think of it as mission control for your body. It even controls https://socialmedia.xdme.com/tony/videos-book10/page-051.mp4 https://www.youtube.com/embed/DG-fEJ2WGc8 110 2026-10-03T02:46:40+00:00 yes https://xdme.com/watch-book10-q052.html https://xdme.com/book10-thumbs/page-052.jpg Why Do Brains Have Wrinkles? Brains have wrinkles because folds pack more thinking surface into your skull! The outer layer, called the cortex, is like a big sheet. Folding it lets a lot of it fit in a head th https://socialmedia.xdme.com/tony/videos-book10/page-052.mp4 https://www.youtube.com/embed/_JHeFDkgXDw 108 2026-10-03T02:49:13+00:00 yes https://xdme.com/watch-book10-q053.html https://xdme.com/book10-thumbs/page-053.jpg Why Do Neurons ‘Talk’ with Sparks and Chemicals? Neurons talk with sparks and chemicals because that is how a message can travel along a cell and then jump to the next one! Electrical impulses race along each neuron. Then chemica https://socialmedia.xdme.com/tony/videos-book10/page-053.mp4 https://www.youtube.com/embed/oaWh1wdvsgU 116 2026-10-03T02:52:17+00:00 yes https://xdme.com/watch-book10-q054.html https://xdme.com/book10-thumbs/page-054.jpg Why Do Growing Kids Need More Hours of Sleep than Adults? Growing kids need more hours of sleep than adults because their bodies and brains are growing fast! Sleep helps with growth, memory, and mood. Many school-age kids need around 9 to https://socialmedia.xdme.com/tony/videos-book10/page-054.mp4 https://www.youtube.com/embed/GLamw1Hf99w 110 2026-10-03T02:54:49+00:00 yes https://xdme.com/watch-book10-q055.html https://xdme.com/book10-thumbs/page-055.jpg Why Do We Forget Most of Our Dreams Soon After Waking? You forget most dreams soon after waking because the memory-saving parts of your brain are less active as you wake up! Dreams fade fast unless you think about them right away. That https://socialmedia.xdme.com/tony/videos-book10/page-055.mp4 https://www.youtube.com/embed/Bw3ruX8-mPw 108 2026-10-03T02:57:22+00:00 yes https://xdme.com/watch-book10-q056.html https://xdme.com/book10-thumbs/page-056.jpg Why Do Nightmares Feel So Real? Nightmares feel so real because the emotion centers of your brain can run strong while the thinking part is quieter during sleep! So scary dreams can feel vivid and big. If a night https://socialmedia.xdme.com/tony/videos-book10/page-056.mp4 https://www.youtube.com/embed/GuuUyE3dZEc 111 2026-10-03T03:00:25+00:00 yes https://xdme.com/watch-book10-q057.html https://xdme.com/book10-thumbs/page-057.jpg Why Is a Bedtime Routine Helpful? A bedtime routine helps because predictable cues tell your brain that it is time to wind down! Doing the same calm things in the same order trains your body clock. Bright screens a https://socialmedia.xdme.com/tony/videos-book10/page-057.mp4 https://www.youtube.com/embed/09m0z6geC30 111 2026-10-03T03:02:58+00:00 yes https://xdme.com/watch-book10-q058.html https://xdme.com/book10-thumbs/page-058.jpg Why Can Babies Read Faces Before They Can Talk? Babies can read faces before they can talk because they are born paying close attention to faces! Your face muscles show feelings that other people can read. It is a social languag https://socialmedia.xdme.com/tony/videos-book10/page-058.mp4 https://www.youtube.com/embed/HbEbb0wvahk 119 2026-10-03T03:06:00+00:00 yes https://xdme.com/watch-book10-q059.html https://xdme.com/book10-thumbs/page-059.jpg Why Does Fear Make Your Heart Race? Fear makes your heart race because your body's alarm system is switching on! It is called the fight-or-flight system. It releases alert chemicals so you can react fast. https://socialmedia.xdme.com/tony/videos-book10/page-059.mp4 https://www.youtube.com/embed/tG_mG9uLgwg 108 2026-10-03T03:08:34+00:00 yes https://xdme.com/watch-book10-q060.html https://xdme.com/book10-thumbs/page-060.jpg Why Is It Okay to Say No to a Hug? It is okay to say no to a hug because your body belongs to you! You get to choose who touches it and when. If someone does not listen to your no, tell a trusted grown-up. https://socialmedia.xdme.com/tony/videos-book10/page-060.mp4 https://www.youtube.com/embed/ogALuvLECKg 105 2026-10-03T03:11:38+00:00 yes https://xdme.com/watch-book10-q061.html https://xdme.com/book10-thumbs/page-061.jpg Why Practice Naming Feelings? Naming your feelings helps because words let the thinking part of your brain team up with the feeling part! A feeling with a name is easier to handle. If big feelings are hard, tal https://socialmedia.xdme.com/tony/videos-book10/page-061.mp4 https://www.youtube.com/embed/eNMuhHiRFOM 113 2026-10-03T03:14:10+00:00 yes https://xdme.com/watch-book10-q062.html https://xdme.com/book10-thumbs/page-062.jpg Why Do Habits Form? Habits form because repeating the same cue, routine, and reward builds quick pathways in your brain! Helpful habits free up your attention for new learning. The more you practice, https://socialmedia.xdme.com/tony/videos-book10/page-062.mp4 https://www.youtube.com/embed/KCCXZIJHHv8 110 2026-10-03T03:16:43+00:00 yes https://xdme.com/watch-book10-q063.html https://xdme.com/book10-thumbs/page-063.jpg Why Is Practice Better than One Long Cram? Short, spaced-out practice beats one long cram because spaced practice strengthens memories more than marathon stuffing! Sleep between sessions helps seal what you learned. Little https://socialmedia.xdme.com/tony/videos-book10/page-063.mp4 https://www.youtube.com/embed/Pe7R8tVjioc 112 2026-10-03T03:19:17+00:00 yes https://xdme.com/watch-book10-q064.html https://xdme.com/book10-thumbs/page-064.jpg Why Do You Forget Some Things? You forget some things because forgetting clears clutter and keeps the useful stuff easy to find! Not every detail deserves permanent storage. Forgetting can actually be a feature, https://socialmedia.xdme.com/tony/videos-book10/page-064.mp4 https://www.youtube.com/embed/uMGy5vb_MG4 113 2026-10-03T03:22:20+00:00 yes https://xdme.com/watch-book10-q065.html https://xdme.com/book10-thumbs/page-065.jpg Why Can a Favorite Song Give You Chills? A favorite song can give you chills because music you love can make your brain release feel-good chemicals! Surprising or powerful moments in a song can set off goosebumps. Not eve https://socialmedia.xdme.com/tony/videos-book10/page-065.mp4 https://www.youtube.com/embed/frUiqKSNCvk 111 2026-10-03T03:25:03+00:00 yes https://xdme.com/watch-book10-q066.html https://xdme.com/book10-thumbs/page-066.jpg Why Do Optical Illusions Trick You? Optical illusions trick you because your brain makes guesses based on patterns! Illusions reveal the guessing shortcuts your brain uses. They are fun little bugs in the system. https://socialmedia.xdme.com/tony/videos-book10/page-066.mp4 https://www.youtube.com/embed/Ya_KovYXun4 109 2026-10-03T03:27:37+00:00 yes https://xdme.com/watch-book10-q067.html https://xdme.com/book10-thumbs/page-067.jpg Why Is Curiosity Good for Brains? Curiosity is good for brains because it fires up your motivation circuits and helps memories stick! When you really want to know something, your brain pays closer attention. Questi https://socialmedia.xdme.com/tony/videos-book10/page-067.mp4 https://www.youtube.com/embed/m37YnuAlOLU 116 2026-10-03T03:30:09+00:00 yes https://xdme.com/watch-book10-q068.html https://xdme.com/book10-thumbs/page-068.jpg Why Do You Need Breaks From Screens? You need breaks from screens because your eyes, posture, sleep, and attention all benefit from pauses! Movement snacks help your brain reset. Breaks are fuel, not failure. https://socialmedia.xdme.com/tony/videos-book10/page-068.mp4 https://www.youtube.com/embed/6Du40NJ73qE 114 2026-10-03T03:33:14+00:00 yes https://xdme.com/watch-book10-q069.html https://xdme.com/book10-thumbs/page-069.jpg Why Do Scary Events Make Your Body Feel Jumpy Afterward? After a scare, your body can feel jumpy because its alarm system may stay switched on for a while! You might feel jumpy, tired, or have trouble sleeping. Talking with a trusted gro https://socialmedia.xdme.com/tony/videos-book10/page-069.mp4 https://www.youtube.com/embed/WgkxX6k5dDA 110 2026-10-03T03:35:15+00:00 yes https://xdme.com/watch-book10-q070.html https://xdme.com/book10-thumbs/page-070.jpg Why Does Gratitude Practice Help Some People? Gratitude practice helps some people because noticing good things can shift your attention habits toward balance! It is not fake cheer. It is practice at spotting what is going wel https://socialmedia.xdme.com/tony/videos-book10/page-070.mp4 https://www.youtube.com/embed/cM-F7j2R6ME 113 2026-10-03T03:38:19+00:00 yes https://xdme.com/watch-book10-q071.html https://xdme.com/book10-thumbs/page-071.jpg Why Are Mistakes Useful? Mistakes are useful because they show where your thinking needs an update! Your brain learns from the surprise. It helps to stay kind to yourself while you try again. https://socialmedia.xdme.com/tony/videos-book10/page-071.mp4 https://www.youtube.com/embed/kNUXzUtVVfc 113 2026-10-03T03:40:51+00:00 yes https://xdme.com/watch-book10-q072.html https://xdme.com/book10-thumbs/page-072.jpg Why Do Friends Matter for Brains? Friends matter for brains because social connection helps your body handle stress and adds joy to your day! Humans are wired to belong. Friendship is brain food. https://socialmedia.xdme.com/tony/videos-book10/page-072.mp4 https://www.youtube.com/embed/lH-vsJce3Bw 114 2026-10-03T03:43:59+00:00 yes https://xdme.com/watch-book10-q073.html https://xdme.com/book10-thumbs/page-073.jpg Why Can Worry Shrink with Action Steps? Worry can shrink with action steps because a vague worry just loops around, but a clear next step gives your problem-solving brain a job! Making a small plan can help you feel calm https://socialmedia.xdme.com/tony/videos-book10/page-073.mp4 https://www.youtube.com/embed/_PAwIZrO7Bk 108 2026-10-03T03:46:32+00:00 yes https://xdme.com/watch-book10-q074.html https://xdme.com/book10-thumbs/page-074.jpg Why Protect Your Head in Sports? We protect our heads in sports because brains are soft and precious! Helmets and safety rules lower the risk of injury. If you ever bump your head hard, tell a grown-up right away. https://socialmedia.xdme.com/tony/videos-book10/page-074.mp4 https://www.youtube.com/embed/qvIGBwg5XAE 113 2026-10-03T03:49:04+00:00 yes https://xdme.com/watch-book10-q075.html https://xdme.com/book10-thumbs/page-075.jpg Why Is Thinking About Your Own Thinking Useful? Thinking about your own thinking is useful because noticing how you learn helps you pick better study tricks! It also helps you get along with others and care for your mental healt https://socialmedia.xdme.com/tony/videos-book10/page-075.mp4 https://www.youtube.com/embed/5nqOVF28D6c 112 2026-10-03T03:52:07+00:00 yes https://xdme.com/watch-book10-q076.html https://xdme.com/book10-thumbs/page-076.jpg Why Do People Say You Have Five Senses, or Even More? People say you have five senses because long ago, we named the big five: sight, hearing, taste, smell, and touch. But your body has other sensors working quietly all day. So the nu https://socialmedia.xdme.com/tony/videos-book10/page-076.mp4 https://www.youtube.com/embed/GrqxBKJzBcw 111 2026-10-03T01:13:19+00:00 yes https://xdme.com/watch-book10-q077.html https://xdme.com/book10-thumbs/page-077.jpg Why Do Pupils Change Size? Pupils change size because they are like little doors that control how much light enters your eyes. In dim light they open wide to let more light in. In bright light they shrink to https://socialmedia.xdme.com/tony/videos-book10/page-077.mp4 https://www.youtube.com/embed/pDzGladsIqg 112 2026-10-03T01:13:20+00:00 yes https://xdme.com/watch-book10-q078.html https://xdme.com/book10-thumbs/page-078.jpg Why Are Two Eyes Better for Depth? Two eyes are better for depth because each eye sees the world from a slightly different spot. Your brain compares the two pictures and figures out how far away things are. That giv https://socialmedia.xdme.com/tony/videos-book10/page-078.mp4 https://www.youtube.com/embed/aQYzjiSF-dE 113 2026-10-03T01:13:21+00:00 yes https://xdme.com/watch-book10-q079.html https://xdme.com/book10-thumbs/page-079.jpg Why Does the Blind Spot Exist? The blind spot exists because of where the nerve leaves your eye. That tiny spot has no light sensors, so it cannot see anything. But your brain fills in the gap, so you almost nev https://socialmedia.xdme.com/tony/videos-book10/page-079.mp4 https://www.youtube.com/embed/r38ERlxV8ME 111 2026-10-03T01:13:23+00:00 yes https://xdme.com/watch-book10-q080.html https://xdme.com/book10-thumbs/page-080.jpg Why Do Ears Help with Balance? Your ears help with balance because deep inside them is a motion-sensing system. Tiny tubes filled with fluid and little hairs notice when your head moves. They tell your brain whi https://socialmedia.xdme.com/tony/videos-book10/page-080.mp4 https://www.youtube.com/embed/Xjlcfi8O19Y 109 2026-10-03T01:13:25+00:00 yes https://xdme.com/watch-book10-q081.html https://xdme.com/book10-thumbs/page-081.jpg Why Does Loud Noise Risk Hearing? Loud noise can harm your hearing because the tiny hair cells in your inner ear are delicate! Very loud sound can damage them, and they do not grow back. Keep the volume low, and te https://socialmedia.xdme.com/tony/videos-book10/page-081.mp4 https://www.youtube.com/embed/KH8Cb0e-dc0 110 2026-10-03T01:13:26+00:00 yes https://xdme.com/watch-book10-q082.html https://xdme.com/book10-thumbs/page-082.jpg Why Is It Okay to Cover Your Ears When a Siren Is Very Loud? It is okay to cover your ears when a siren is very loud because very loud sound can hurt your ears. Covering them turns the volume down. And moving away makes it even quieter. https://socialmedia.xdme.com/tony/videos-book10/page-082.mp4 https://www.youtube.com/embed/aMxo49Mv3fs 110 2026-10-03T01:13:28+00:00 yes https://xdme.com/watch-book10-q083.html https://xdme.com/book10-thumbs/page-083.jpg Why Does Smell Warn You of Smoke? Smell warns you of smoke because your nose catches tiny floating molecules very fast! Smoke has a strong smell, so you can notice it before you see flames. If you ever smell smoke, https://socialmedia.xdme.com/tony/videos-book10/page-083.mp4 https://www.youtube.com/embed/ZYTeFI78G-w 117 2026-10-03T01:13:29+00:00 yes https://xdme.com/watch-book10-q084.html https://xdme.com/book10-thumbs/page-084.jpg Why Does Taste Need Saliva? Taste needs saliva because chemicals in food have to dissolve in liquid to reach your taste buds. Saliva is the watery spit in your mouth. Without it, flavors have trouble getting https://socialmedia.xdme.com/tony/videos-book10/page-084.mp4 https://www.youtube.com/embed/glqDoO7jjhU 111 2026-10-03T01:13:30+00:00 yes https://xdme.com/watch-book10-q085.html https://xdme.com/book10-thumbs/page-085.jpg Why Is Touch Not Just One Sense? Touch is not just one sense, because your skin has different sensors for different feelings. Some feel pressure, some feel vibration, and some feel stretch. Others sense temperatur https://socialmedia.xdme.com/tony/videos-book10/page-085.mp4 https://www.youtube.com/embed/GSjxteW5WHE 114 2026-10-03T01:13:32+00:00 yes https://xdme.com/watch-book10-q086.html https://xdme.com/book10-thumbs/page-086.jpg Why Are Your Fingertips So Good at Feeling Small Details? Fingertips are so good at feeling small details because they are packed with touch sensors. Your brain gets lots of information from just a tiny area. That helps you notice tiny bu https://socialmedia.xdme.com/tony/videos-book10/page-086.mp4 https://www.youtube.com/embed/54vtnD4Nijs 110 2026-10-03T01:13:34+00:00 yes https://xdme.com/watch-book10-q087.html https://xdme.com/book10-thumbs/page-087.jpg Why Can You Touch Your Nose with Your Eyes Closed? You can touch your nose with your eyes closed because your body has a sense of where its parts are. Sensors in your muscles and joints send messages to your brain. So your brain kn https://socialmedia.xdme.com/tony/videos-book10/page-087.mp4 https://www.youtube.com/embed/TGqdJ2_0Ys4 111 2026-10-03T01:13:35+00:00 yes https://xdme.com/watch-book10-q088.html https://xdme.com/book10-thumbs/page-088.jpg Why Do You Sweat and Get a Runny Nose When You Eat Spicy Food? Spicy food makes you sweat and sniffle because chili fools your heat sensors. The spicy chemical in chili touches the same nerves that notice real heat. So your body acts as if you https://socialmedia.xdme.com/tony/videos-book10/page-088.mp4 https://www.youtube.com/embed/amr-yba_GxM 116 2026-10-03T01:13:36+00:00 yes https://xdme.com/watch-book10-q089.html https://xdme.com/book10-thumbs/page-089.jpg Why Do Your Eyes Get Red and Puffy When You Cry? Your eyes get red and puffy when you cry because crying makes lots of tears and changes the blood vessels around your eyes. Extra tears flow into your nose, which is why you sniffl https://socialmedia.xdme.com/tony/videos-book10/page-089.mp4 https://www.youtube.com/embed/zeTtXhewPRs 112 2026-10-03T01:13:37+00:00 yes https://xdme.com/watch-book10-q090.html https://xdme.com/book10-thumbs/page-090.jpg Why Wear Sunglasses in Bright Glare? We wear sunglasses in bright glare because bright sunlight can bother and harm our eyes! Good sunglasses cut the glare and block the invisible UV light from the Sun. Never stare st https://socialmedia.xdme.com/tony/videos-book10/page-090.mp4 https://www.youtube.com/embed/4Kp-NSwDQc4 112 2026-10-03T01:13:39+00:00 yes https://xdme.com/watch-book10-q091.html https://xdme.com/book10-thumbs/page-091.jpg Why Does Motion Sickness Happen? Motion sickness happens when the signals from your eyes, inner ears, and body do not match! Your brain gets mixed-up messages, and that can make your tummy feel queasy. It is very https://socialmedia.xdme.com/tony/videos-book10/page-091.mp4 https://www.youtube.com/embed/5gy7wrvTx_Q 106 2026-10-03T01:13:41+00:00 yes https://xdme.com/watch-book10-q092.html https://xdme.com/book10-thumbs/page-092.jpg Why Do Some People Have Trouble Telling Red From Green? Some people have trouble telling red from green because the color cells in their eyes work a little differently. They were born that way, and it does not hurt. It is just a differe https://socialmedia.xdme.com/tony/videos-book10/page-092.mp4 https://www.youtube.com/embed/tOKzoOkYBCQ 112 2026-10-03T01:14:43+00:00 yes https://xdme.com/watch-book10-q093.html https://xdme.com/book10-thumbs/page-093.jpg Why Does Closing Your Eyes Make You Notice Sounds More? Closing your eyes makes you notice sounds more because your brain has less to look at. Your attention can shift to hearing, almost like turning a spotlight toward sound. So quiet s https://socialmedia.xdme.com/tony/videos-book10/page-093.mp4 https://www.youtube.com/embed/Q1ImNWlJ6VE 110 2026-10-03T01:16:47+00:00 yes https://xdme.com/watch-book10-q094.html https://xdme.com/book10-thumbs/page-094.jpg Why Do Glasses Have Curved Lenses? Glasses have curved lenses because curved glass bends light! Your eye needs light to land exactly on the retina at the back, and if it lands in the wrong spot, things look blurry. https://socialmedia.xdme.com/tony/videos-book10/page-094.mp4 https://www.youtube.com/embed/uSt3jH9XsWo 109 2026-10-03T01:19:49+00:00 yes https://xdme.com/watch-book10-q095.html https://xdme.com/book10-thumbs/page-095.jpg Why Do People Learn Braille and Sign Languages? People learn Braille and sign languages because words can travel in more ways than just spoken sounds. Braille uses touch, and sign languages use hands, faces, and movement. These https://socialmedia.xdme.com/tony/videos-book10/page-095.mp4 https://www.youtube.com/embed/rGvO-i5SmV4 117 2026-10-03T01:22:22+00:00 yes https://xdme.com/watch-book10-q096.html https://xdme.com/book10-thumbs/page-096.jpg Why Do Some Nerves Sense Cold and Others Sense Heat? Some nerves sense cold and others sense heat because your skin and mouth have different receptors for each. Cold receptors wake up when things cool down, and heat receptors wake up https://socialmedia.xdme.com/tony/videos-book10/page-096.mp4 https://www.youtube.com/embed/2VmV_M_uDRU 112 2026-10-03T01:24:55+00:00 yes https://xdme.com/watch-book10-q097.html https://xdme.com/book10-thumbs/page-097.jpg Why Can Your Nose Smell Cookies From Across the House? You can smell cookies from across the house because tiny scent molecules float through the air. They travel into your nose and land on special sensors. So you can smell food before https://socialmedia.xdme.com/tony/videos-book10/page-097.mp4 https://www.youtube.com/embed/vSDMkujR-1k 110 2026-10-03T01:27:58+00:00 yes https://xdme.com/watch-book10-q098.html https://xdme.com/book10-thumbs/page-098.jpg Why Do Small Brave Steps Help with Mild Fears? Small brave steps help with mild fears because they teach your alarm system that you are safe. Your body has a built-in alarm that protects you, but sometimes it rings when there i https://socialmedia.xdme.com/tony/videos-book10/page-098.mp4 https://www.youtube.com/embed/-70RM_xBdts 112 2026-10-03T01:30:32+00:00 yes https://xdme.com/watch-book10-q099.html https://xdme.com/book10-thumbs/page-099.jpg Why Are Smoke Detectors Better than Noses Alone? Smoke detectors are better than noses alone because your nose does not wake you up well when you are asleep. You might sleep right through an early smoke smell. A smoke detector ke https://socialmedia.xdme.com/tony/videos-book10/page-099.mp4 https://www.youtube.com/embed/B_E0XQAssd0 110 2026-10-03T01:33:05+00:00 yes https://xdme.com/watch-book10-q100.html https://xdme.com/book10-thumbs/page-100.jpg Why Train Your Senses on Purpose? We train our senses on purpose because paying close attention gets better with practice. Musicians, athletes, and scientists all practice noticing small details. The more you pract https://socialmedia.xdme.com/tony/videos-book10/page-100.mp4 https://www.youtube.com/embed/OlzUMsd7WoE 115 2026-10-03T01:35:36+00:00 yes https://xdme.com/watch-book10-q101.html https://xdme.com/book10-thumbs/page-101.jpg Why Do We Wash Cuts? We wash cuts because dirt and tiny microbes can sneak into your skin through the opening! Cleaning a cut removes dirt and lowers the number of germs. Tell a grown-up about any cut, https://socialmedia.xdme.com/tony/videos-book10/page-101.mp4 https://www.youtube.com/embed/J-xBx6B2Z7g 107 2026-10-03T01:38:40+00:00 yes https://xdme.com/watch-book10-q102.html https://xdme.com/book10-thumbs/page-102.jpg Why Does a Bruise Turn Purple, Then Green, Then Yellow? A bruise changes color because your body is cleaning up leaked blood! When tiny blood vessels under the skin break, a little blood gets trapped, and as your body breaks it down the https://socialmedia.xdme.com/tony/videos-book10/page-102.mp4 https://www.youtube.com/embed/J7CajH8NURY 106 2026-10-03T01:41:16+00:00 yes https://xdme.com/watch-book10-q103.html https://xdme.com/book10-thumbs/page-103.jpg Why Do Vaccines Train Your Immune System? Vaccines train your immune system by showing it a safe practice version of a germ! Your body learns to recognize the germ without getting the full sickness. Doctors and nurses give https://socialmedia.xdme.com/tony/videos-book10/page-103.mp4 https://www.youtube.com/embed/BiFi3Ma4hs0 108 2026-10-03T01:44:19+00:00 yes https://xdme.com/watch-book10-q104.html https://xdme.com/book10-thumbs/page-104.jpg Why Does a Fever Make You Feel Hot and Shivery? A fever makes you feel hot and shivery because your brain turns up your body's thermostat! A warmer body can help fight germs, and while it heats up you can feel cold and shivery. https://socialmedia.xdme.com/tony/videos-book10/page-104.mp4 https://www.youtube.com/embed/YOJdLYgKy3o 111 2026-10-03T01:46:52+00:00 yes https://xdme.com/watch-book10-q105.html https://xdme.com/book10-thumbs/page-105.jpg Why Do Coughs and Sneezes Need a Tissue or Your Elbow? Coughs and sneezes need a tissue or your elbow because they blast tiny droplets into the air. Those droplets can carry germs to other people. A tissue or your elbow catches most of https://socialmedia.xdme.com/tony/videos-book10/page-105.mp4 https://www.youtube.com/embed/4S76YrOmEY4 107 2026-10-03T01:49:24+00:00 yes https://xdme.com/watch-book10-q106.html https://xdme.com/book10-thumbs/page-106.jpg Why Do Lymph Nodes Swell When You’re Sick? Lymph nodes swell when you are sick because they are busy places where immune cells gather! Inside them, immune cells meet germs and make more fighters. If a lump is sore or does n https://socialmedia.xdme.com/tony/videos-book10/page-106.mp4 https://www.youtube.com/embed/MFOx1LWOl5k 108 2026-10-03T01:52:27+00:00 yes https://xdme.com/watch-book10-q107.html https://xdme.com/book10-thumbs/page-107.jpg Why Are Antibiotics Wrong for Colds? Antibiotics are the wrong tool for colds because most colds are caused by viruses, and antibiotics only work on bacteria! Using them when they are not needed will not help you get https://socialmedia.xdme.com/tony/videos-book10/page-107.mp4 https://www.youtube.com/embed/MSI5J17ZwcU 118 2026-10-03T01:55:00+00:00 yes https://xdme.com/watch-book10-q108.html https://xdme.com/book10-thumbs/page-108.jpg Why Do You Feel Sleepy When You Are Sick? You feel sleepy when you are sick because sleep helps your body fight germs. While you rest, your body puts extra energy into immune work and repair. So sleeping more when you are https://socialmedia.xdme.com/tony/videos-book10/page-108.mp4 https://www.youtube.com/embed/ooSD5cpEsLw 106 2026-10-03T01:57:31+00:00 yes https://xdme.com/watch-book10-q109.html https://xdme.com/book10-thumbs/page-109.jpg Why Eat Yogurt with Live Cultures Sometimes? Some people eat yogurt with live cultures because it adds friendly microbes to the food you eat! These microbes may help keep the helpful bacteria in your gut balanced. It is not a https://socialmedia.xdme.com/tony/videos-book10/page-109.mp4 https://www.youtube.com/embed/CpJIG_3x7GE 114 2026-10-03T02:00:35+00:00 yes https://xdme.com/watch-book10-q110.html https://xdme.com/book10-thumbs/page-110.jpg Why Does Itching Happen Around Healing Skin? Healing skin itches because the repair work can tickle tiny nerves! Your body makes chemicals like histamine as part of healing, and they can make skin tingle and itch. Try not to https://socialmedia.xdme.com/tony/videos-book10/page-110.mp4 https://www.youtube.com/embed/oxAM8izqmUw 109 2026-10-03T02:03:08+00:00 yes https://xdme.com/watch-book10-q111.html https://xdme.com/book10-thumbs/page-111.jpg Why Use Sunscreen? We use sunscreen because sunlight has UV rays that can burn skin and harm skin cells! Sunscreen works like a shield, blocking or absorbing some of the rays. Ask a grown-up to help https://socialmedia.xdme.com/tony/videos-book10/page-111.mp4 https://www.youtube.com/embed/PmN_RxKmi44 109 2026-10-03T02:05:39+00:00 yes https://xdme.com/watch-book10-q112.html https://xdme.com/book10-thumbs/page-112.jpg Why Do Allergies Happen? Allergies happen when your immune system overreacts to something harmless, like pollen! It treats that harmless thing like a dangerous invader and sets off a false alarm, with snif https://socialmedia.xdme.com/tony/videos-book10/page-112.mp4 https://www.youtube.com/embed/EMfCGvFsfDA 113 2026-10-03T02:08:54+00:00 yes https://xdme.com/watch-book10-q113.html https://xdme.com/book10-thumbs/page-113.jpg Why Do Some People Carry an Epinephrine Auto-Injector? Some people carry an epinephrine auto-injector because they could have a severe allergic reaction! That kind of reaction can come on fast and needs medicine and emergency help righ https://socialmedia.xdme.com/tony/videos-book10/page-113.mp4 https://www.youtube.com/embed/e8xVx1PjArU 123 2026-10-03T02:11:29+00:00 yes https://xdme.com/watch-book10-q114.html https://xdme.com/book10-thumbs/page-114.jpg Why Brush and Floss Teeth? We brush and floss because a sticky film of bacteria grows on your teeth all day. That film makes acids that can etch into the hard outside of your teeth, called enamel. Cleaning b https://socialmedia.xdme.com/tony/videos-book10/page-114.mp4 https://www.youtube.com/embed/yYNc7mlRoUQ 110 2026-10-03T02:14:02+00:00 yes https://xdme.com/watch-book10-q115.html https://xdme.com/book10-thumbs/page-115.jpg Why Do Dentist Visits Matter Even Without Pain? Dentist visits matter even without pain because many tooth problems start small and quietly. A dentist can spot them early and fix them while they are easy. Prevention beats a toot https://socialmedia.xdme.com/tony/videos-book10/page-115.mp4 https://www.youtube.com/embed/YXk1uaciUyU 112 2026-10-03T02:16:34+00:00 yes https://xdme.com/watch-book10-q116.html https://xdme.com/book10-thumbs/page-116.jpg Why Stay Home From School When You Are Contagious? We stay home from school when we are contagious because resting helps us recover. It also keeps our germs away from classmates and teachers. Kindness includes not sharing viruses! https://socialmedia.xdme.com/tony/videos-book10/page-116.mp4 https://www.youtube.com/embed/-V-jsLnDfKU 109 2026-10-03T02:19:05+00:00 yes https://xdme.com/watch-book10-q117.html https://xdme.com/book10-thumbs/page-117.jpg Why Do Stitches Help Some Cuts? Stitches help some cuts because they hold the edges of the skin together! That helps deeper wounds heal faster and neater, and they work like a temporary zipper. A doctor decides w https://socialmedia.xdme.com/tony/videos-book10/page-117.mp4 https://www.youtube.com/embed/uzV93AxNEcQ 109 2026-10-03T02:22:09+00:00 yes https://xdme.com/watch-book10-q118.html https://xdme.com/book10-thumbs/page-118.jpg Why Is Smoke Bad for Healing Lungs? Smoke is bad for healing lungs because it irritates your airways. It also makes it harder for oxygen to get into your blood. Fresh air helps your lungs repair themselves, which is https://socialmedia.xdme.com/tony/videos-book10/page-118.mp4 https://www.youtube.com/embed/n9xvbp5wP9k 113 2026-10-03T02:24:41+00:00 yes https://xdme.com/watch-book10-q119.html https://xdme.com/book10-thumbs/page-119.jpg Why Do People with Arm Casts Need to Raise the Arm Sometimes? People with arms in casts are sometimes told to raise the arm because elevation helps reduce swelling. When the arm is higher, extra fluid can drain away more easily. That helps th https://socialmedia.xdme.com/tony/videos-book10/page-119.mp4 https://www.youtube.com/embed/-CZs1Ou9mQc 108 2026-10-03T02:27:14+00:00 yes https://xdme.com/watch-book10-q120.html https://xdme.com/book10-thumbs/page-120.jpg Why Keep Tetanus Shots Updated? We keep tetanus shots updated because tetanus bacteria live in dirt and can cause serious illness. The vaccine trains your body to defend against them, before you ever meet them. B https://socialmedia.xdme.com/tony/videos-book10/page-120.mp4 https://www.youtube.com/embed/Uoa-mWKZul0 115 2026-10-03T02:30:17+00:00 yes https://xdme.com/watch-book10-q121.html https://xdme.com/book10-thumbs/page-121.jpg Why Hydrate When You Have Diarrhea or Fever? We drink extra fluids when we have diarrhea or a fever because the body loses extra water and salts! Replacing those fluids helps prevent dehydration, which is when your body gets https://socialmedia.xdme.com/tony/videos-book10/page-121.mp4 https://www.youtube.com/embed/8OHUBeLTrt8 113 2026-10-03T02:32:50+00:00 yes https://xdme.com/watch-book10-q122.html https://xdme.com/book10-thumbs/page-122.jpg Why Do Scars Fade Over Time But Never Disappear? Scars fade over time but never fully disappear because scar tissue is built differently from normal skin. It is made of tough collagen fibers in a different pattern. So a scar is a https://socialmedia.xdme.com/tony/videos-book10/page-122.mp4 https://www.youtube.com/embed/cxZaEo8c-Kk 112 2026-10-03T02:35:54+00:00 yes https://xdme.com/watch-book10-q123.html https://xdme.com/book10-thumbs/page-123.jpg Why Should You Listen to Pharmacists About Storing Medicine? You should listen to pharmacists about storing medicine because heat, light, and humidity can spoil it! Spoiled medicine may not work the way it should or may not be safe. Medicine https://socialmedia.xdme.com/tony/videos-book10/page-123.mp4 https://www.youtube.com/embed/RIRlWJR3sGU 115 2026-10-03T02:38:32+00:00 yes https://xdme.com/watch-book10-q124.html https://xdme.com/book10-thumbs/page-124.jpg Why Is Handwashing a Community Superpower? Handwashing is a community superpower because it cuts down how many germs pass from hand to hand. Your clean hands protect the people you love. Even a small habit can help a whole https://socialmedia.xdme.com/tony/videos-book10/page-124.mp4 https://www.youtube.com/embed/3bKZ_Is3R84 114 2026-10-03T02:41:36+00:00 yes https://xdme.com/watch-book10-q125.html https://xdme.com/book10-thumbs/page-125.jpg Why Should You Finish Antibiotics When the Doctor Says To? You should finish antibiotics when the doctor says to because stopping early can leave tougher bacteria behind! Those survivors can grow and make you sick again, and they might be https://socialmedia.xdme.com/tony/videos-book10/page-125.mp4 https://www.youtube.com/embed/xEKXpRmdU4w 112 2026-10-03T02:44:09+00:00 yes https://xdme.com/watch-book10-q126.html https://xdme.com/book10-thumbs/page-126.jpg Why Eat Colorful Meals? We eat colorful meals because different plants bring different nutrients and fibers. One favorite food cannot cover everything your body needs. Variety covers more needs, like a to https://socialmedia.xdme.com/tony/videos-book10/page-126.mp4 https://www.youtube.com/embed/NjJ5Y0E0v34 114 2026-10-03T02:46:41+00:00 yes https://xdme.com/watch-book10-q127.html https://xdme.com/book10-thumbs/page-127.jpg Why Does Protein Help You Grow and Repair? Protein helps you grow and repair because it is made of tiny building blocks called amino acids. Your body uses them to build and fix muscles, skin, hair, and more. Growing bodies https://socialmedia.xdme.com/tony/videos-book10/page-127.mp4 https://www.youtube.com/embed/UJYYq7KLPbs 114 2026-10-03T02:49:15+00:00 yes https://xdme.com/watch-book10-q128.html https://xdme.com/book10-thumbs/page-128.jpg Why Limit Sugary Drinks? We limit sugary drinks because liquid sugar adds lots of energy fast without making you feel full. Sugar also bathes your teeth in food for bacteria. Water is the hero drink for mo https://socialmedia.xdme.com/tony/videos-book10/page-128.mp4 https://www.youtube.com/embed/H677J2l_BFI 111 2026-10-03T02:52:18+00:00 yes https://xdme.com/watch-book10-q129.html https://xdme.com/book10-thumbs/page-129.jpg Why Does Breakfast Help Many Kids? Breakfast helps many kids because your body has been fasting all night while you slept. Morning food gives your body and brain fuel to start the day, so you can think and play. A s https://socialmedia.xdme.com/tony/videos-book10/page-129.mp4 https://www.youtube.com/embed/jyQYaSbcS40 112 2026-10-03T02:54:50+00:00 yes https://xdme.com/watch-book10-q130.html https://xdme.com/book10-thumbs/page-130.jpg Why Is It Smart to Sip Water Before You Feel Thirsty? It is smart to sip water before you feel thirsty because thirst is a late signal. By the time you feel thirsty, your body already needs water. Sipping through the day keeps you ahe https://socialmedia.xdme.com/tony/videos-book10/page-130.mp4 https://www.youtube.com/embed/-TpXSndHL5o 106 2026-10-03T02:57:23+00:00 yes https://xdme.com/watch-book10-q131.html https://xdme.com/book10-thumbs/page-131.jpg Why Schedule Outdoor Play? We schedule outdoor play because daylight, movement, and nature time are good for your body and mind. They support your mood and your sleep, and they make play more fun. Sunlight a https://socialmedia.xdme.com/tony/videos-book10/page-131.mp4 https://www.youtube.com/embed/jVmzF7oYlgU 115 2026-10-03T03:00:26+00:00 yes https://xdme.com/watch-book10-q132.html https://xdme.com/book10-thumbs/page-132.jpg Why Do Both Strength and Cardio Matter? Both strength and cardio matter because your heart, lungs, and muscles do different jobs. Cardio builds your heart and lung fitness, and gives you stamina. Strength builds your mus https://socialmedia.xdme.com/tony/videos-book10/page-132.mp4 https://www.youtube.com/embed/CvWFaKCrudI 113 2026-10-03T03:02:59+00:00 yes https://xdme.com/watch-book10-q133.html https://xdme.com/book10-thumbs/page-133.jpg Why Stretch After Sitting for a Long Time? We stretch after sitting for a long time because joints and muscles get stiff when they stay in one position. A short movement break helps them feel comfortable again. It can even https://socialmedia.xdme.com/tony/videos-book10/page-133.mp4 https://www.youtube.com/embed/S17xlJ84B7s 105 2026-10-03T03:06:02+00:00 yes https://xdme.com/watch-book10-q134.html https://xdme.com/book10-thumbs/page-134.jpg Why Is a Steady Sleep Schedule Better than Staying Up Late on Weekends? A steady sleep schedule is better because your body has an inner clock that likes consistency. Big bedtime swings on weekends confuse that clock, so Mondays feel harder. A steady s https://socialmedia.xdme.com/tony/videos-book10/page-134.mp4 https://www.youtube.com/embed/GeNZiQHk8fU 112 2026-10-03T03:09:06+00:00 yes https://xdme.com/watch-book10-q135.html https://xdme.com/book10-thumbs/page-135.jpg Why Manage Screen Time with Family Rules? We manage screen time with family rules because balance protects your sleep, posture, homework, and play. Screens can be fun and useful, but too much can crowd out other healthy th https://socialmedia.xdme.com/tony/videos-book10/page-135.mp4 https://www.youtube.com/embed/QPTzBB0k2Yg 115 2026-10-03T03:11:39+00:00 yes https://xdme.com/watch-book10-q136.html https://xdme.com/book10-thumbs/page-136.jpg Why Should You Replace Your Toothbrush Every Few Months? You should replace your toothbrush every few months because the bristles wear out and bend. A worn brush cleans less well, and it can collect germs, especially after you have been https://socialmedia.xdme.com/tony/videos-book10/page-136.mp4 https://www.youtube.com/embed/_33wqV0fu8w 109 2026-10-03T03:14:12+00:00 yes https://xdme.com/watch-book10-q137.html https://xdme.com/book10-thumbs/page-137.jpg Why Wear Seat Belts? We wear seat belts because they spread crash forces across the strongest parts of your body. They also keep you in the safer part of the car, and not thrown around. Buckle up on ev https://socialmedia.xdme.com/tony/videos-book10/page-137.mp4 https://www.youtube.com/embed/Id0-7vJMdhw 109 2026-10-03T03:16:44+00:00 yes https://xdme.com/watch-book10-q138.html https://xdme.com/book10-thumbs/page-138.jpg Why Learn Basic First Aid? Learning basic first aid is smart because knowing what to do turns bystanders into helpers! You can clean a scrape, call for help, and stay calm. Always get a grown-up right away i https://socialmedia.xdme.com/tony/videos-book10/page-138.mp4 https://www.youtube.com/embed/Y6iX4bUq5kM 111 2026-10-03T03:19:48+00:00 yes https://xdme.com/watch-book10-q139.html https://xdme.com/book10-thumbs/page-139.jpg Why Tell a Trusted Adult About Bullying or Big Stress? You should tell a trusted adult about bullying or big stress because stress and worry affect both your mind and your body. Telling a trusted adult gets you help and support. And th https://socialmedia.xdme.com/tony/videos-book10/page-139.mp4 https://www.youtube.com/embed/YGbwvRosFEQ 112 2026-10-03T03:22:21+00:00 yes https://xdme.com/watch-book10-q140.html https://xdme.com/book10-thumbs/page-140.jpg Why Do Annual Checkups Matter? Annual checkups matter because they track your growth and keep your health on course. A doctor can update vaccines, check hearing and vision, and answer your questions. Catching is https://socialmedia.xdme.com/tony/videos-book10/page-140.mp4 https://www.youtube.com/embed/aGpNocZac3k 109 2026-10-03T03:25:04+00:00 yes https://xdme.com/watch-book10-q141.html https://xdme.com/book10-thumbs/page-141.jpg Why Does Your Neck Get Tired When You Look Down at a Screen? Your neck gets tired when you look down at a screen because your head is heavy. Tipping it forward makes your neck and back muscles work extra hard to hold it up. Raising your scre https://socialmedia.xdme.com/tony/videos-book10/page-141.mp4 https://www.youtube.com/embed/I93oMeklpfE 103 2026-10-03T03:27:38+00:00 yes https://xdme.com/watch-book10-q142.html https://xdme.com/book10-thumbs/page-142.jpg Why Do Muscles Feel Sore a Day After Something New? Muscles can feel sore a day after something new because hard or unfamiliar activity strains the muscle fibers! Your body repairs them, and that repair can feel sore a day later. If https://socialmedia.xdme.com/tony/videos-book10/page-142.mp4 https://www.youtube.com/embed/fifgJGiwcfA 110 2026-10-03T03:30:11+00:00 yes https://xdme.com/watch-book10-q143.html https://xdme.com/book10-thumbs/page-143.jpg Why Cook Together as a Habit? Cooking together is a great habit because you learn about nutrition, chemistry, and teamwork! Kitchen time builds skills you can use for life, like reading recipes and measuring. A https://socialmedia.xdme.com/tony/videos-book10/page-143.mp4 https://www.youtube.com/embed/NtYNE2d6BAg 110 2026-10-03T03:32:43+00:00 yes https://xdme.com/watch-book10-q144.html https://xdme.com/book10-thumbs/page-144.jpg Why Limit Energy Drinks for Kids? We limit energy drinks for kids because they have lots of caffeine and other stimulants. Those can be hard on growing bodies and can mess up sleep. Most kids do not need them at al https://socialmedia.xdme.com/tony/videos-book10/page-144.mp4 https://www.youtube.com/embed/4LfXyZW7i9g 108 2026-10-03T03:35:18+00:00 yes https://xdme.com/watch-book10-q145.html https://xdme.com/book10-thumbs/page-145.jpg Why Can Mindfulness or Quiet Time Help Your Body? Mindfulness or quiet time can help your body because short calm practices can lower stress signals. They can also help you focus, and feel more steady when things are busy. Calm is https://socialmedia.xdme.com/tony/videos-book10/page-145.mp4 https://www.youtube.com/embed/8OzMLUQrT5E 112 2026-10-03T03:38:20+00:00 yes https://xdme.com/watch-book10-q146.html https://xdme.com/book10-thumbs/page-146.jpg Why Track How Your Habits Make You Feel? Tracking how your habits make you feel is smart because notes show which routines help you personally. Energy, mood, and sleep can change from day to day, in ways you might not not https://socialmedia.xdme.com/tony/videos-book10/page-146.mp4 https://www.youtube.com/embed/etlW8ni0Pss 107 2026-10-03T03:40:58+00:00 yes https://xdme.com/watch-book10-q147.html https://xdme.com/book10-thumbs/page-147.jpg Why Include Joyful Movement, Not Only Formal Exercise? Joyful movement counts because fun makes habits stick. Dancing, biking, and playing games build a strong heart without the dread of a boring workout. Any movement you enjoy counts https://socialmedia.xdme.com/tony/videos-book10/page-147.mp4 https://www.youtube.com/embed/OoSfAD-yok0 110 2026-10-03T03:44:00+00:00 yes https://xdme.com/watch-book10-q148.html https://xdme.com/book10-thumbs/page-148.jpg Why Does Your Body Send Warning Signs, Like Dizziness, When It Gets Too Hot? Your body sends warning signs like dizziness when it gets too hot because it is asking for help! If it cannot cool down enough, it sends signals so you will take a break. Move to s https://socialmedia.xdme.com/tony/videos-book10/page-148.mp4 https://www.youtube.com/embed/Llgfm9jQdWE 106 2026-10-03T03:46:33+00:00 yes https://xdme.com/watch-book10-q149.html https://xdme.com/book10-thumbs/page-149.jpg Why Be Kind to Bodies of All Shapes? We should be kind to bodies of all shapes because healthy habits matter more than comparing looks. Bodies differ because of genes, age, and abilities. Respect is part of health too https://socialmedia.xdme.com/tony/videos-book10/page-149.mp4 https://www.youtube.com/embed/Fcuk1iVp8DE 112 2026-10-03T03:49:06+00:00 yes https://xdme.com/watch-book10-q150.html https://xdme.com/book10-thumbs/page-150.jpg Why Do Doctors and Scientists Still Have So Much to Learn About the Human Body? Doctors and scientists still have so much to learn about the human body because it is amazingly complicated. They are still discovering how the brain, gut microbes, and even sleep https://socialmedia.xdme.com/tony/videos-book10/page-150.mp4 https://www.youtube.com/embed/9RKEGhC9k9Y 110 2026-10-03T03:52:09+00:00 yes https://xdme.com/watch-book11-q001.html https://xdme.com/book11-thumbs/page-001.jpg Why Do Mammals Have Fur or Hair? Mammals have fur or hair because it works like a built-in blanket! Hair traps a layer of air next to the skin, which keeps body heat in. Some animals grow thick coats, and some gro https://socialmedia.xdme.com/tony/videos-book11/page-001.mp4 https://www.youtube.com/embed/TgV7iKnHXmw 115 2026-10-03T04:06:23+00:00 yes https://xdme.com/watch-book11-q002.html https://xdme.com/book11-thumbs/page-002.jpg Why Do Birds Have Feathers Instead of Fur? Birds have feathers because feathers can do jobs that fur cannot! They are light and strong, and they are shaped for flying, staying warm, and keeping dry. Fur would be heavy and s https://socialmedia.xdme.com/tony/videos-book11/page-002.mp4 https://www.youtube.com/embed/5EOUZNZ0lxU 110 2026-10-03T04:06:01+00:00 yes https://xdme.com/watch-book11-q003.html https://xdme.com/book11-thumbs/page-003.jpg What Are Reptile Scales Made Of? Reptile scales are made of keratin, the same tough stuff as your fingernails! The scales are thin, hard plates that cover the whole body like a suit of armor. They protect the rept https://socialmedia.xdme.com/tony/videos-book11/page-003.mp4 https://www.youtube.com/embed/Xe7P23t8ZOI 112 2026-10-03T04:08:30+00:00 yes https://xdme.com/watch-book11-q004.html https://xdme.com/book11-thumbs/page-004.jpg Why Do Some Animals Shed Their Coats? Many animals shed or molt because they need to swap an old coat for a new one! Molting means dropping old fur or feathers so fresh ones can grow in. It is like a planned wardrobe c https://socialmedia.xdme.com/tony/videos-book11/page-004.mp4 https://www.youtube.com/embed/rYE1LIg3-oU 106 2026-10-03T04:11:32+00:00 yes https://xdme.com/watch-book11-q005.html https://xdme.com/book11-thumbs/page-005.jpg Why Do Polar Bears Look White If Their Skin Is Black? A polar bear looks white because its hairs scatter light, not because they are white! Each hair is clear and has no color of its own. Under all that fur, the bear's skin is black. https://socialmedia.xdme.com/tony/videos-book11/page-005.mp4 https://www.youtube.com/embed/LuwmDVdwkfc 107 2026-10-03T04:14:34+00:00 yes https://xdme.com/watch-book11-q006.html https://xdme.com/book11-thumbs/page-006.jpg Why Do Peacocks Have Such Fancy Feathers? A peacock's fancy train is a signal to peahens! A healthy male can grow a bigger, brighter train, so it tells her, I am strong. Peahens usually choose the males with the best displ https://socialmedia.xdme.com/tony/videos-book11/page-006.mp4 https://www.youtube.com/embed/TaKvc3T_ows 115 2026-10-03T04:17:39+00:00 yes https://xdme.com/watch-book11-q007.html https://xdme.com/book11-thumbs/page-007.jpg Why Do Pangolins Roll Into a Ball? A pangolin rolls into a ball because its scales turn it into armor! When a predator comes near, it curls up tight and tucks its tail over its face. Even a hungry lion has a hard ti https://socialmedia.xdme.com/tony/videos-book11/page-007.mp4 https://www.youtube.com/embed/BTafyfue1OM 110 2026-10-03T04:20:10+00:00 yes https://xdme.com/watch-book11-q008.html https://xdme.com/book11-thumbs/page-008.jpg Why Do Frogs Feel Slimy? Frogs feel slimy because their skin is covered in a thin layer of mucus! The slime keeps the skin moist, and a frog can even take in some air through wet skin. If you see a wild fr https://socialmedia.xdme.com/tony/videos-book11/page-008.mp4 https://www.youtube.com/embed/dkD2eDtSM3Y 111 2026-10-03T04:23:13+00:00 yes https://xdme.com/watch-book11-q009.html https://xdme.com/book11-thumbs/page-009.jpg Why Do Armadillos Wear Armor? An armadillo wears armor because it gives the animal a shield on its back! Bony plates covered with tough skin protect its back, head, and tail. The plates are joined in bands so t https://socialmedia.xdme.com/tony/videos-book11/page-009.mp4 https://www.youtube.com/embed/WV3W-QwcE8Y 110 2026-10-03T04:26:16+00:00 yes https://xdme.com/watch-book11-q010.html https://xdme.com/book11-thumbs/page-010.jpg Why Do Lions Have Manes? Male lions have manes because a mane protects and shows off! A thick mane cushions the neck and head during fights with rivals. It also works like a sign that says, I am healthy an https://socialmedia.xdme.com/tony/videos-book11/page-010.mp4 https://www.youtube.com/embed/85EVjE9Wcos 105 2026-10-03T04:28:49+00:00 yes https://xdme.com/watch-book11-q011.html https://xdme.com/book11-thumbs/page-011.jpg Why Do Cats’ Fur Stand Up When They’re Scared? A scared cat's fur stands up to make the cat look bigger! Tiny muscles at the base of each hair pull the hair upright. It is a bluff that tells another animal, back off, without a https://socialmedia.xdme.com/tony/videos-book11/page-011.mp4 https://www.youtube.com/embed/JnpXnYovblI 108 2026-10-03T04:31:52+00:00 yes https://xdme.com/watch-book11-q012.html https://xdme.com/book11-thumbs/page-012.jpg Why Can’t a Turtle Crawl Out of Its Shell? A turtle can't crawl out of its shell because the shell is part of its skeleton! The top shell is joined to the backbone and ribs, and the bottom shell is part of the skeleton too. https://socialmedia.xdme.com/tony/videos-book11/page-012.mp4 https://www.youtube.com/embed/bO99m12ns2E 107 2026-10-03T04:34:25+00:00 yes https://xdme.com/watch-book11-q013.html https://xdme.com/book11-thumbs/page-013.jpg Why Do Elephants Have Almost No Fur? Elephants have almost no fur because they are huge and live in hot places! A big body makes heat and loses it slowly. Thick fur would trap even more heat, so elephants cool off in https://socialmedia.xdme.com/tony/videos-book11/page-013.mp4 https://www.youtube.com/embed/rouRH2qpOyc 108 2026-10-03T04:37:30+00:00 yes https://xdme.com/watch-book11-q014.html https://xdme.com/book11-thumbs/page-014.jpg Why Do Sloths Have Green Fur? A sloth looks green because tiny green algae grow in its fur! Its hairs have small grooves, and the rain keeps them damp. Algae like that, so the sloth turns into a moving garden. https://socialmedia.xdme.com/tony/videos-book11/page-014.mp4 https://www.youtube.com/embed/9nXoOK85yQk 107 2026-10-03T04:40:01+00:00 yes https://xdme.com/watch-book11-q015.html https://xdme.com/book11-thumbs/page-015.jpg Why Are Blue Jays Blue Without Any Blue Color in Their Feathers? A blue jay is blue because of how its feathers bounce light, not because of blue paint! Tiny structures inside each feather reflect blue light back to your eyes. Other colors are a https://socialmedia.xdme.com/tony/videos-book11/page-015.mp4 https://www.youtube.com/embed/05t7KY9dKiM 110 2026-10-03T04:42:34+00:00 yes https://xdme.com/watch-book11-q016.html https://xdme.com/book11-thumbs/page-016.jpg Why Do Lizards Drop Their Tails? Many lizards drop their tails on purpose to escape! The tail breaks off at a weak spot, and the piece keeps wiggling for a while. That distracts a predator while the lizard runs to https://socialmedia.xdme.com/tony/videos-book11/page-016.mp4 https://www.youtube.com/embed/NkqbCc3W4UY 109 2026-10-03T04:45:36+00:00 yes https://xdme.com/watch-book11-q017.html https://xdme.com/book11-thumbs/page-017.jpg Why Do Worms Not Have Fur, Feathers, or Scales? Worms have no fur, feathers, or scales because they breathe through their skin! An earthworm's skin has to stay thin and moist so air can pass through. A coat would only get in the https://socialmedia.xdme.com/tony/videos-book11/page-017.mp4 https://www.youtube.com/embed/AzGNlNL8ELs 108 2026-10-03T04:48:15+00:00 yes https://xdme.com/watch-book11-q018.html https://xdme.com/book11-thumbs/page-018.jpg Why Do Penguins Have Dense Feathers? Penguins have dense feathers to stay warm and dry in icy water! Their short, stiff feathers are packed tightly, with fluffy ones underneath. The layers trap air close to the skin. https://socialmedia.xdme.com/tony/videos-book11/page-018.mp4 https://www.youtube.com/embed/2-mEzY5KWy8 114 2026-10-03T04:51:21+00:00 yes https://xdme.com/watch-book11-q019.html https://xdme.com/book11-thumbs/page-019.jpg Why Do Hippos Ooze a Red-Orange “Sweat”? A hippo's red-orange ooze is not blood and not sweat! The thick liquid has special colored chemicals in it that work like a natural lotion and help block the Sun's rays. Hippos can https://socialmedia.xdme.com/tony/videos-book11/page-019.mp4 https://www.youtube.com/embed/me42oDC6Lmw 108 2026-10-03T04:53:55+00:00 yes https://xdme.com/watch-book11-q020.html https://xdme.com/book11-thumbs/page-020.jpg Why Do Some Animals Change Color with the Seasons? Some animals change color with the seasons to hide! Arctic foxes, snowshoe hares, and ptarmigans grow white coats or feathers for winter. Then they grow brown ones for summer. https://socialmedia.xdme.com/tony/videos-book11/page-020.mp4 https://www.youtube.com/embed/lnMZAPKYsUM 109 2026-10-03T04:56:59+00:00 yes https://xdme.com/watch-book11-q021.html https://xdme.com/book11-thumbs/page-021.jpg Why Do Rhinos Have Thick Skin Folds? Rhinos have thick skin folds to protect their big bodies! The thick skin guards against thorny bushes, sunburn, and biting insects. The deep folds let the heavy animal bend and wal https://socialmedia.xdme.com/tony/videos-book11/page-021.mp4 https://www.youtube.com/embed/0fX7slvUgCA 108 2026-10-03T05:00:04+00:00 yes https://xdme.com/watch-book11-q022.html https://xdme.com/book11-thumbs/page-022.jpg Why Do Bees Look Fuzzy? Bees look fuzzy because their bodies are covered in branched hairs! The hairs help bees collect and carry pollen from flower to flower. They also keep a bee warm and help it feel t https://socialmedia.xdme.com/tony/videos-book11/page-022.mp4 https://www.youtube.com/embed/tjipTyxK6ZQ 108 2026-10-03T05:03:08+00:00 yes https://xdme.com/watch-book11-q023.html https://xdme.com/book11-thumbs/page-023.jpg Why Does Shark Skin Feel Like Sandpaper? Shark skin feels like sandpaper because it is covered in tiny tooth-shaped scales! These little scales are called denticles. They point backward toward the tail, a bit like the shi https://socialmedia.xdme.com/tony/videos-book11/page-023.mp4 https://www.youtube.com/embed/Lgdb4aygPis 109 2026-10-03T05:05:42+00:00 yes https://xdme.com/watch-book11-q024.html https://xdme.com/book11-thumbs/page-024.jpg Why Do Birds Fluff Up Their Feathers When It Is Cold? Birds fluff up their feathers in the cold to trap warm air! Still air is a great insulator, just like the filling in a puffy winter jacket. A fluffed-up bird can look like a round https://socialmedia.xdme.com/tony/videos-book11/page-024.mp4 https://www.youtube.com/embed/X6HAEHzOxKk 107 2026-10-03T05:08:45+00:00 yes https://xdme.com/watch-book11-q025.html https://xdme.com/book11-thumbs/page-025.jpg Why Do Animals Need Skin Care From Nature? Animals take care of their skin, fur, and feathers in many clever ways! Birds roll in dust or preen their feathers with oil. Elephants spray dust and mud on their backs, and cats l https://socialmedia.xdme.com/tony/videos-book11/page-025.mp4 https://www.youtube.com/embed/tcREmgU5_Yk 110 2026-10-03T05:11:51+00:00 yes https://xdme.com/watch-book11-q026.html https://xdme.com/book11-thumbs/page-026.jpg Why Do Dogs Smell So Much Better than Humans? Dogs smell so much better than people because they have far more scent sensors! A dog has about 300 million of them in its nose, and a person has about 6 million. The part of a dog https://socialmedia.xdme.com/tony/videos-book11/page-026.mp4 https://www.youtube.com/embed/zF-XFeYzq_s 110 2026-10-03T05:14:36+00:00 yes https://xdme.com/watch-book11-q027.html https://xdme.com/book11-thumbs/page-027.jpg How Do Pit Vipers Sense Heat? Pit vipers sense heat with two small pits on their faces! Each pit sits between an eye and a nostril. The pits sense heat, which is invisible infrared light from warm animals. https://socialmedia.xdme.com/tony/videos-book11/page-027.mp4 https://www.youtube.com/embed/4MmXpne5OJg 111 2026-10-03T05:17:39+00:00 yes https://xdme.com/watch-book11-q028.html https://xdme.com/book11-thumbs/page-028.jpg Why Do Butterflies Taste with Their Feet? Butterflies taste with their feet because they need to pick the right leaf! Taste sensors on the feet tell a butterfly if a plant is food for its caterpillars. Only then does she l https://socialmedia.xdme.com/tony/videos-book11/page-028.mp4 https://www.youtube.com/embed/i9Yi7ixl_h0 108 2026-10-03T05:20:17+00:00 yes https://xdme.com/watch-book11-q029.html https://xdme.com/book11-thumbs/page-029.jpg Why Do Snakes Flick Their Tongues? Snakes flick their tongues to smell the world! A snake's tongue collects tiny scent particles from the air and ground, and the snake then checks them with a special spot in its mou https://socialmedia.xdme.com/tony/videos-book11/page-029.mp4 https://www.youtube.com/embed/qsfb-MhiWgQ 109 2026-10-03T05:23:20+00:00 yes https://xdme.com/watch-book11-q030.html https://xdme.com/book11-thumbs/page-030.jpg Why Do Chameleons’ Eyes Move Separately? A chameleon can move each eye separately, so it can look in two directions at once! Each eye moves like its own little camera. That helps it scan all around without moving its body https://socialmedia.xdme.com/tony/videos-book11/page-030.mp4 https://www.youtube.com/embed/9NOHHF4n7O4 110 2026-10-03T05:26:06+00:00 yes https://xdme.com/watch-book11-q031.html https://xdme.com/book11-thumbs/page-031.jpg Why Are Some Owls’ Ears at Different Heights? Some owls have ears at different heights to help them find sounds in the dark! A sound from above reaches one ear a tiny bit before the other. By comparing the tiny differences, th https://socialmedia.xdme.com/tony/videos-book11/page-031.mp4 https://www.youtube.com/embed/df2LKNAKp_w 113 2026-10-03T05:29:18+00:00 yes https://xdme.com/watch-book11-q032.html https://xdme.com/book11-thumbs/page-032.jpg Why Do Elephants Hear with Their Feet? Elephants can pick up faraway rumbles through their feet! Elephants make deep rumbles, and some are too low for people to hear. These sounds travel through the air and through the https://socialmedia.xdme.com/tony/videos-book11/page-032.mp4 https://www.youtube.com/embed/e3WvA3vHMe4 114 2026-10-03T05:31:49+00:00 yes https://xdme.com/watch-book11-q033.html https://xdme.com/book11-thumbs/page-033.jpg How Do Fish Feel the Water Moving Around Them? Fish feel water moving with a special line of sensors along their sides! It is called the lateral line. It works a bit like feeling the water with your skin. https://socialmedia.xdme.com/tony/videos-book11/page-033.mp4 https://www.youtube.com/embed/qFH7Gep6nYY 110 2026-10-03T05:34:28+00:00 yes https://xdme.com/watch-book11-q034.html https://xdme.com/book11-thumbs/page-034.jpg Why Does the Star-Nosed Mole Have a Nose Shaped Like a Star? A star-nosed mole has a star-shaped nose because the star is a super touch sensor! It has 22 pink tentacles covered in tiny touch sensors. It taps them on the ground very fast to f https://socialmedia.xdme.com/tony/videos-book11/page-034.mp4 https://www.youtube.com/embed/v0NMgW7xgRM 108 2026-10-03T05:37:01+00:00 yes https://xdme.com/watch-book11-q035.html https://xdme.com/book11-thumbs/page-035.jpg Why Can a Platypus Find Food with Its Eyes Closed? A platypus can find food with its eyes closed because its bill senses tiny electric signals! When it dives, it closes its eyes, ears, and nostrils. Its bill still works and helps i https://socialmedia.xdme.com/tony/videos-book11/page-035.mp4 https://www.youtube.com/embed/_DvS8xp2bUw 111 2026-10-03T05:40:05+00:00 yes https://xdme.com/watch-book11-q036.html https://xdme.com/book11-thumbs/page-036.jpg Why Do Cats Have Whiskers? Cats have whiskers because whiskers are super-sensitive feelers! They are long, stiff hairs rooted deep in the skin with many nerves. Even a tiny bend tells the cat something. https://socialmedia.xdme.com/tony/videos-book11/page-036.mp4 https://www.youtube.com/embed/3bwk3Jb9yeo 110 2026-10-03T05:42:37+00:00 yes https://xdme.com/watch-book11-q037.html https://xdme.com/book11-thumbs/page-037.jpg Why Do Some Moths Have Feathery Antennae? Male moths often have feathery antennae to catch scents in the air! The tiny branches give the antenna lots of surface for catching scent molecules. It works like a net for smells. https://socialmedia.xdme.com/tony/videos-book11/page-037.mp4 https://www.youtube.com/embed/kLs8lE-X9Gc 112 2026-10-03T05:45:10+00:00 yes https://xdme.com/watch-book11-q038.html https://xdme.com/book11-thumbs/page-038.jpg Why Do Deer Flash White Tails? A white-tailed deer flashes its tail to send a warning! When danger is near, it raises its tail and shows the bright white underside. The whole group knows to run. https://socialmedia.xdme.com/tony/videos-book11/page-038.mp4 https://www.youtube.com/embed/PIQjmw1FzE8 105 2026-10-03T05:47:49+00:00 yes https://xdme.com/watch-book11-q039.html https://xdme.com/book11-thumbs/page-039.jpg How Do Homing Pigeons Find Their Way Home? Homing pigeons use several clues to find their way home! They can sense Earth's magnetic field, and they use the Sun's position. They also notice landmarks and may even smell famil https://socialmedia.xdme.com/tony/videos-book11/page-039.mp4 https://www.youtube.com/embed/5BhN5q_GRoU 111 2026-10-03T05:50:52+00:00 yes https://xdme.com/watch-book11-q040.html https://xdme.com/book11-thumbs/page-040.jpg Why Do Rattlesnakes Rattle? A rattlesnake rattles to warn animals and people to stay back! It shakes the end of its tail, which is made of loose rings of keratin, and the buzzing sound says, I'm here. If you https://socialmedia.xdme.com/tony/videos-book11/page-040.mp4 https://www.youtube.com/embed/CkD457B13EM 107 2026-10-03T05:53:55+00:00 yes https://xdme.com/watch-book11-q041.html https://xdme.com/book11-thumbs/page-041.jpg How Do Mosquitoes Find People? Female mosquitoes find people by following several clues at once! They sense the carbon dioxide in our breath from far away. Then they use smell, warmth, and movement to get closer https://socialmedia.xdme.com/tony/videos-book11/page-041.mp4 https://www.youtube.com/embed/UqI7HMRY-tA 118 2026-10-03T05:57:01+00:00 yes https://xdme.com/watch-book11-q042.html https://xdme.com/book11-thumbs/page-042.jpg Why Do Rabbits Thump the Ground? Rabbits thump the ground to warn each other! A rabbit stamps its strong back feet to make a loud thump. The thump travels through the ground, so other rabbits feel and hear it. https://socialmedia.xdme.com/tony/videos-book11/page-042.mp4 https://www.youtube.com/embed/7bM1ObPUOWM 108 2026-10-03T05:59:33+00:00 yes https://xdme.com/watch-book11-q043.html https://xdme.com/book11-thumbs/page-043.jpg How Do Spiders Feel a Bug Land in Their Web? A spider's web is also a sensor! When an insect lands, the threads shake, and the spider feels the shaking and knows something is there. It can tell a struggling bug from a leaf bl https://socialmedia.xdme.com/tony/videos-book11/page-043.mp4 https://www.youtube.com/embed/lGvf6F0jSO4 107 2026-10-03T06:02:05+00:00 yes https://xdme.com/watch-book11-q044.html https://xdme.com/book11-thumbs/page-044.jpg Why Do Goats Have Rectangular Pupils? Goats have rectangular pupils to see a wide view of the ground! The pupils are horizontal slots, not round circles like ours. Sheep have them too, and so do many other animals that https://socialmedia.xdme.com/tony/videos-book11/page-044.mp4 https://www.youtube.com/embed/JNiTwDRqjk4 107 2026-10-03T06:05:07+00:00 yes https://xdme.com/watch-book11-q045.html https://xdme.com/book11-thumbs/page-045.jpg Why Do Sharks Sense Tiny Electric Twitches? Sharks sense tiny electric signals with special pores near their snouts! All animals give off very weak electricity when their muscles move. A shark can sense it even when prey is https://socialmedia.xdme.com/tony/videos-book11/page-045.mp4 https://www.youtube.com/embed/Ke49wfll5D0 110 2026-10-03T06:08:10+00:00 yes https://xdme.com/watch-book11-q046.html https://xdme.com/book11-thumbs/page-046.jpg Why Do Prairie Dogs “Speak” in Chirps? Prairie dogs chirp because their calls carry information about danger! They have different calls for different dangers. Scientists have found that the calls can describe the visito https://socialmedia.xdme.com/tony/videos-book11/page-046.mp4 https://www.youtube.com/embed/Ul1zG6-Qefw 114 2026-10-03T06:10:42+00:00 yes https://xdme.com/watch-book11-q047.html https://xdme.com/book11-thumbs/page-047.jpg Why Do Octopuses Taste with Their Arms? Octopuses taste with their arms because their suckers have taste sensors! Each sucker has taste and touch sensors. So when an arm touches something, it can taste it at the same tim https://socialmedia.xdme.com/tony/videos-book11/page-047.mp4 https://www.youtube.com/embed/Vq95NDpd7Pk 110 2026-10-03T06:13:15+00:00 yes https://xdme.com/watch-book11-q048.html https://xdme.com/book11-thumbs/page-048.jpg Why Do Meerkats Take Turns as Lookouts? Meerkats take turns as lookouts so the whole group can stay safe! One meerkat, called the sentinel, stands on a high spot and watches for danger. The others can dig for insects, so https://socialmedia.xdme.com/tony/videos-book11/page-048.mp4 https://www.youtube.com/embed/OwTJ7eqOdyw 111 2026-10-03T06:15:47+00:00 yes https://xdme.com/watch-book11-q049.html https://xdme.com/book11-thumbs/page-049.jpg Why Do Catfish Taste with Their Whole Bodies? Catfish taste with their whole bodies because taste sensors cover their skin! They also have extra ones on their whiskers, called barbels. So they can taste food in the water witho https://socialmedia.xdme.com/tony/videos-book11/page-049.mp4 https://www.youtube.com/embed/dzXDDdmoZC4 109 2026-10-03T06:18:20+00:00 yes https://xdme.com/watch-book11-q050.html https://xdme.com/book11-thumbs/page-050.jpg Why Can’t Snakes Blink? Snakes can't blink because they have no movable eyelids! Instead, each eye is covered by a clear scale. It works like a built-in pair of goggles. https://socialmedia.xdme.com/tony/videos-book11/page-050.mp4 https://www.youtube.com/embed/5ZJwIn0pE5U 105 2026-10-03T06:20:57+00:00 yes https://xdme.com/watch-book11-q051.html https://xdme.com/book11-thumbs/page-051.jpg Why Do Wolves Live in Packs? Wolves live in packs because a pack is really a family, and families can do big jobs together! A pack is usually a mother, a father, and their young. Teamwork helps them hunt, prot https://socialmedia.xdme.com/tony/videos-book11/page-051.mp4 https://www.youtube.com/embed/DE60pubFeYE 117 2026-10-03T06:23:41+00:00 yes https://xdme.com/watch-book11-q052.html https://xdme.com/book11-thumbs/page-052.jpg Why Do Baby Ducklings Follow Their Mother in a Line? Baby ducklings follow their mother in a line because they learn to follow the first big moving thing they see! That is usually their mom, and following her keeps them safe. The lin https://socialmedia.xdme.com/tony/videos-book11/page-052.mp4 https://www.youtube.com/embed/-7SGlBRrHro 113 2026-10-03T06:26:14+00:00 yes https://xdme.com/watch-book11-q053.html https://xdme.com/book11-thumbs/page-053.jpg Why Do Elephants Follow a Matriarch? Elephants follow a matriarch because she is the wise old leader of the herd! A matriarch is an older female who remembers where to find food and water. Younger elephants follow her https://socialmedia.xdme.com/tony/videos-book11/page-053.mp4 https://www.youtube.com/embed/i_oEUFOV3js 111 2026-10-03T06:29:18+00:00 yes https://xdme.com/watch-book11-q054.html https://xdme.com/book11-thumbs/page-054.jpg Why Does a Beehive Have Just One Queen? A beehive has just one queen because she is the egg layer for the whole hive! She lays almost all of the eggs, and her scent keeps the hive calm. Everyone else has a different job https://socialmedia.xdme.com/tony/videos-book11/page-054.mp4 https://www.youtube.com/embed/IjAlb9guywI 104 2026-10-03T06:31:19+00:00 yes https://xdme.com/watch-book11-q055.html https://xdme.com/book11-thumbs/page-055.jpg How Do Lionesses Hunt as a Team? Lionesses hunt as a team because working together works better than going alone! Each lioness plays a different role in the hunt. A team has a much better chance of success. https://socialmedia.xdme.com/tony/videos-book11/page-055.mp4 https://www.youtube.com/embed/zZRuqyBireo 108 2026-10-03T06:34:04+00:00 yes https://xdme.com/watch-book11-q056.html https://xdme.com/book11-thumbs/page-056.jpg Why Do Orcas Teach Calves to Hunt? Orcas teach their calves to hunt because hunting is a skill that has to be learned! Young orcas learn by watching their families, and each family has its own traditions. Those less https://socialmedia.xdme.com/tony/videos-book11/page-056.mp4 https://www.youtube.com/embed/BtfSixY7kB8 118 2026-10-03T06:36:39+00:00 yes https://xdme.com/watch-book11-q057.html https://xdme.com/book11-thumbs/page-057.jpg How Do Ant Colonies Divide Up the Work? Ant colonies divide up the work because each ant has a job, like in a tiny city! The queen lays eggs, and the workers do almost everything else. Dividing up the work lets a colony https://socialmedia.xdme.com/tony/videos-book11/page-057.mp4 https://www.youtube.com/embed/C_1ZpmO67WA 111 2026-10-03T06:39:41+00:00 yes https://xdme.com/watch-book11-q058.html https://xdme.com/book11-thumbs/page-058.jpg Why Do Birds Nest in Colonies? Birds nest in colonies because there is safety in numbers! In a big group, many eyes can spot danger and give the alarm. Colonies are also often near plenty of food. https://socialmedia.xdme.com/tony/videos-book11/page-058.mp4 https://www.youtube.com/embed/C0FsgeKxFeI 110 2026-10-03T06:42:14+00:00 yes https://xdme.com/watch-book11-q059.html https://xdme.com/book11-thumbs/page-059.jpg Why Do Beaver Families Build Together? Beaver families build together because the work is big, and every beaver can help! Kits learn from their parents and older brothers and sisters. Together they build a safe home and https://socialmedia.xdme.com/tony/videos-book11/page-059.mp4 https://www.youtube.com/embed/7M9setnX0DI 111 2026-10-03T06:44:47+00:00 yes https://xdme.com/watch-book11-q060.html https://xdme.com/book11-thumbs/page-060.jpg Why Do Kangaroo Joeys Stay in Pouches? Kangaroo joeys stay in their pouches because they are born so tiny! The pouch is a warm, safe nursery that goes wherever mom goes. Inside, the joey drinks milk and grows. https://socialmedia.xdme.com/tony/videos-book11/page-060.mp4 https://www.youtube.com/embed/8UBiL1hKXS4 107 2026-10-03T06:46:50+00:00 yes https://xdme.com/watch-book11-q061.html https://xdme.com/book11-thumbs/page-061.jpg Why Do Seahorse Dads Carry the Babies? Seahorse dads carry the babies because they have a special belly pouch for the eggs! That makes seahorses one of the very few animals where dads are the ones who carry the young. T https://socialmedia.xdme.com/tony/videos-book11/page-061.mp4 https://www.youtube.com/embed/xyrwHzJDJgw 111 2026-10-03T06:49:53+00:00 yes https://xdme.com/watch-book11-q062.html https://xdme.com/book11-thumbs/page-062.jpg Why Do African Wild Dogs Vote with Sneezes? African wild dogs vote with sneezes, which is a quiet way to decide when to go hunting! Before a hunt, the pack gathers for a greeting. Scientists found that enough sneezes mean it https://socialmedia.xdme.com/tony/videos-book11/page-062.mp4 https://www.youtube.com/embed/dICDHkM9VOQ 113 2026-10-03T06:52:57+00:00 yes https://xdme.com/watch-book11-q063.html https://xdme.com/book11-thumbs/page-063.jpg Why Do Swans Mate for Long Partnerships? Swans often stay with the same partner for many years, because a good team makes a good family! Having a partner helps them guard the nest and raise their cygnets. Pairs that know https://socialmedia.xdme.com/tony/videos-book11/page-063.mp4 https://www.youtube.com/embed/N0bX_t84zOw 110 2026-10-03T06:54:58+00:00 yes https://xdme.com/watch-book11-q064.html https://xdme.com/book11-thumbs/page-064.jpg Why Do Squirrels Sometimes Raise Orphans? Squirrels sometimes raise orphans because relatives can help each other out! Squirrels usually care for their own young, but sometimes a mother adopts babies that have lost their m https://socialmedia.xdme.com/tony/videos-book11/page-064.mp4 https://www.youtube.com/embed/-WjFplNMdbk 116 2026-10-03T06:58:01+00:00 yes https://xdme.com/watch-book11-q065.html https://xdme.com/book11-thumbs/page-065.jpg Why Do Zebras and Wildebeest Travel Together? Zebras and wildebeest travel together because they make a great team! Each one is good at something different. Together they spot danger sooner. https://socialmedia.xdme.com/tony/videos-book11/page-065.mp4 https://www.youtube.com/embed/aQ1BdIrrWRo 115 2026-10-03T07:00:35+00:00 yes https://xdme.com/watch-book11-q066.html https://xdme.com/book11-thumbs/page-066.jpg Why Do Naked Mole Rats Share Tunnels? Naked mole rats share tunnels because they live in big underground colonies, a bit like ants! One queen has the babies, and everyone else has a job. Working as a team makes digging https://socialmedia.xdme.com/tony/videos-book11/page-066.mp4 https://www.youtube.com/embed/206aVpvjJ_o 113 2026-10-03T07:03:15+00:00 yes https://xdme.com/watch-book11-q067.html https://xdme.com/book11-thumbs/page-067.jpg Why Do Starlings Fly in Giant Swirling Clouds? Starlings fly in giant swirling clouds because each bird copies its closest neighbors! There is no leader at all. The swirls also make it hard for a hawk to pick out one bird. https://socialmedia.xdme.com/tony/videos-book11/page-067.mp4 https://www.youtube.com/embed/YphOIY1BpLA 115 2026-10-03T07:05:51+00:00 yes https://xdme.com/watch-book11-q068.html https://xdme.com/book11-thumbs/page-068.jpg Why Do Baby Birds Open Their Mouths So Wide? Baby birds open their mouths so wide because it is a signal that says, Feed me! A big, wide beak is easy for parents to see and aim at. Parents bring food over and over, so the chi https://socialmedia.xdme.com/tony/videos-book11/page-068.mp4 https://www.youtube.com/embed/Dy60UTf-eqI 107 2026-10-03T07:08:24+00:00 yes https://xdme.com/watch-book11-q069.html https://xdme.com/book11-thumbs/page-069.jpg Why Do Orangutan Moms Stay with Young So Long? Orangutan moms stay with their young for so long because there is a lot to learn! Orangutans live in the treetops, and life up there is complicated. Mom is the main teacher. https://socialmedia.xdme.com/tony/videos-book11/page-069.mp4 https://www.youtube.com/embed/_I1AGdX2jAI 112 2026-10-03T07:11:28+00:00 yes https://xdme.com/watch-book11-q070.html https://xdme.com/book11-thumbs/page-070.jpg Why Do Dolphins Babysit Each Other’s Calves? Dolphins babysit each other's calves because it takes a team to raise little ones! In some groups, adults watch the calves while the mothers go hunting. That keeps the calves safe https://socialmedia.xdme.com/tony/videos-book11/page-070.mp4 https://www.youtube.com/embed/OOCifwdPT5Y 112 2026-10-03T07:14:02+00:00 yes https://xdme.com/watch-book11-q071.html https://xdme.com/book11-thumbs/page-071.jpg Why Do Leafcutter Ants Farm Fungus? Leafcutter ants farm fungus because the fungus is their food! The ants cut up leaves, but they don't eat the leaves. They use the leaves to feed a fungus, and then they eat the fun https://socialmedia.xdme.com/tony/videos-book11/page-071.mp4 https://www.youtube.com/embed/bFR5Lyh44cI 107 2026-10-03T07:16:35+00:00 yes https://xdme.com/watch-book11-q072.html https://xdme.com/book11-thumbs/page-072.jpg Why Do Wolves Bring Food to Den Pups? Wolves bring food to the den pups because the pups are too little to travel far! The pack brings meals home to them. Delivering meals keeps the next generation healthy and growing. https://socialmedia.xdme.com/tony/videos-book11/page-072.mp4 https://www.youtube.com/embed/cOMYqBY_Yl0 108 2026-10-03T07:19:40+00:00 yes https://xdme.com/watch-book11-q073.html https://xdme.com/book11-thumbs/page-073.jpg Why Do Emperor Penguin Dads Hold Eggs? Emperor penguin dads hold the eggs because the moms need to go to sea to eat! Dad keeps the egg warm through the freezing Antarctic winter. It is a big job, and he does it without https://socialmedia.xdme.com/tony/videos-book11/page-073.mp4 https://www.youtube.com/embed/rXEIw6LnHaI 110 2026-10-03T07:22:20+00:00 yes https://xdme.com/watch-book11-q074.html https://xdme.com/book11-thumbs/page-074.jpg Why Do Crows Remember Human Faces? Crows remember human faces because they have very good memories! Studies show that crows can remember individual people for years. Remembering faces helps crows stay safe. https://socialmedia.xdme.com/tony/videos-book11/page-074.mp4 https://www.youtube.com/embed/qbw3yV82RxY 114 2026-10-03T07:24:55+00:00 yes https://xdme.com/watch-book11-q075.html https://xdme.com/book11-thumbs/page-075.jpg Why Do Animal “Families” Sometimes Include Friends? Animal families sometimes include friends because not everyone in a group is related! Some animals live with unrelated friends who help them. Friends can help animals survive. https://socialmedia.xdme.com/tony/videos-book11/page-075.mp4 https://www.youtube.com/embed/-1xITIuxnD8 112 2026-10-03T07:28:10+00:00 yes https://xdme.com/watch-book11-q076.html https://xdme.com/book11-thumbs/page-076.jpg How Do Jumping Spiders Hunt Without a Web? Jumping spiders hunt without a web because they have amazing eyesight and a super pounce! They don't wait for dinner to get stuck. They stalk their prey, sneak closer, and leap. https://socialmedia.xdme.com/tony/videos-book11/page-076.mp4 https://www.youtube.com/embed/KiiMqdIhLPI 110 2026-10-03T04:06:03+00:00 yes https://xdme.com/watch-book11-q077.html https://xdme.com/book11-thumbs/page-077.jpg Why Do Cheetahs Have Tear-Mark Lines? Cheetahs have tear-mark lines because those dark stripes may work like sunglasses! The lines run from the inside corner of each eye down to the mouth. Scientists think they help th https://socialmedia.xdme.com/tony/videos-book11/page-077.mp4 https://www.youtube.com/embed/s1iEI3Avx4Y 111 2026-10-03T04:06:05+00:00 yes https://xdme.com/watch-book11-q078.html https://xdme.com/book11-thumbs/page-078.jpg Why Do Pelicans Scoop Fish with Their Big Bills? Pelicans scoop fish with their big bills because the pouch works like a built-in net! It stretches wide and holds lots of water and fish. Then the pelican squeezes out the water an https://socialmedia.xdme.com/tony/videos-book11/page-078.mp4 https://www.youtube.com/embed/rJfk8JZB5Xc 112 2026-10-03T04:07:58+00:00 yes https://xdme.com/watch-book11-q079.html https://xdme.com/book11-thumbs/page-079.jpg Why Do Anglerfish Use Glowing Lures? Anglerfish use glowing lures because the deep ocean is completely dark! The lure is a fishing rod with a glowing tip. Small fish are curious and swim right up to the light. https://socialmedia.xdme.com/tony/videos-book11/page-079.mp4 https://www.youtube.com/embed/aIUXdMfz8nY 111 2026-10-03T04:11:33+00:00 yes https://xdme.com/watch-book11-q080.html https://xdme.com/book11-thumbs/page-080.jpg Why Do Venomous Snakes Have Venom? Venomous snakes have venom because it helps them catch food and stay safe! Venom is a special kind of saliva with strong chemicals. Most snakes are not venomous and bite only when https://socialmedia.xdme.com/tony/videos-book11/page-080.mp4 https://www.youtube.com/embed/9bn_Bg89hng 116 2026-10-03T04:14:36+00:00 yes https://xdme.com/watch-book11-q081.html https://xdme.com/book11-thumbs/page-081.jpg Why Do Bombardier Beetles Spray Hot Liquid? Bombardier beetles spray a hot, smelly liquid as a super defense! The spray surprises and scares off hungry ants and frogs, and the beetle makes it with a clever chemistry trick in https://socialmedia.xdme.com/tony/videos-book11/page-081.mp4 https://www.youtube.com/embed/hHeLvCsJejc 113 2026-10-03T04:17:07+00:00 yes https://xdme.com/watch-book11-q082.html https://xdme.com/book11-thumbs/page-082.jpg Why Do Octopuses Squirt Ink? Octopuses squirt ink because it helps them escape when they are scared! The dark cloud is a decoy, and it gives the octopus time to get away. It is a quick and clever disappearing https://socialmedia.xdme.com/tony/videos-book11/page-082.mp4 https://www.youtube.com/embed/GKOs0FZFVz8 108 2026-10-03T04:20:42+00:00 yes https://xdme.com/watch-book11-q083.html https://xdme.com/book11-thumbs/page-083.jpg Why Do Some Caterpillars Look Like Snakes? Some caterpillars look like snakes because it helps scare away hungry birds! Big spots on their heads look like snake eyes. A quick glance can fool a bird. https://socialmedia.xdme.com/tony/videos-book11/page-083.mp4 https://www.youtube.com/embed/Lr23k_MnHGc 113 2026-10-03T04:23:14+00:00 yes https://xdme.com/watch-book11-q084.html https://xdme.com/book11-thumbs/page-084.jpg Why Do Honeyguide Birds Lead People to Honey? Honeyguide birds in Africa lead people to honey because both of them get a treat! The bird knows where wild bees' nests are, and people can open them. The bird eats the leftover wa https://socialmedia.xdme.com/tony/videos-book11/page-084.mp4 https://www.youtube.com/embed/SCbIP049fjI 113 2026-10-03T04:26:18+00:00 yes https://xdme.com/watch-book11-q085.html https://xdme.com/book11-thumbs/page-085.jpg Why Do Oxpeckers Ride on Rhinos? Oxpeckers ride on rhinos and other big animals to eat ticks and other bugs off their skin! The rhino gets cleaned, and the bird gets a meal. Scientists have found that oxpeckers so https://socialmedia.xdme.com/tony/videos-book11/page-085.mp4 https://www.youtube.com/embed/vObEki4rWL0 114 2026-10-03T04:29:21+00:00 yes https://xdme.com/watch-book11-q086.html https://xdme.com/book11-thumbs/page-086.jpg Why Do Arctic Foxes Follow Polar Bears? Arctic foxes follow polar bears because the bears leave tasty scraps behind! In winter, food is hard to find in the Arctic. Following a bear can be a smart way for a small fox to e https://socialmedia.xdme.com/tony/videos-book11/page-086.mp4 https://www.youtube.com/embed/FYn_7JkIewA 111 2026-10-03T04:31:53+00:00 yes https://xdme.com/watch-book11-q087.html https://xdme.com/book11-thumbs/page-087.jpg Why Do Antlions Dig Tiny Pits in the Sand? Antlions dig tiny pits in the sand because the pits are sneaky traps for ants! The sand is so loose that the sides slide away. An ant that steps in slips down toward the bottom. https://socialmedia.xdme.com/tony/videos-book11/page-087.mp4 https://www.youtube.com/embed/Jeb4lXf4kuI 110 2026-10-03T04:34:26+00:00 yes https://xdme.com/watch-book11-q088.html https://xdme.com/book11-thumbs/page-088.jpg Why Do Frogs Use Sticky Tongues? Frogs use sticky tongues because they are the perfect bug catchers! A frog's tongue is soft, quick, and covered in sticky saliva. It flips out, grabs the insect, and is back in a f https://socialmedia.xdme.com/tony/videos-book11/page-088.mp4 https://www.youtube.com/embed/c2BSH820w3c 107 2026-10-03T04:36:58+00:00 yes https://xdme.com/watch-book11-q089.html https://xdme.com/book11-thumbs/page-089.jpg Why Do Eagles Have Talons? Eagles have talons because those strong, curved claws are perfect for catching food! An eagle's feet work like a pair of powerful hands. Once the toes lock on, the grip is hard to https://socialmedia.xdme.com/tony/videos-book11/page-089.mp4 https://www.youtube.com/embed/Pd9sTFosiLA 109 2026-10-03T04:40:02+00:00 yes https://xdme.com/watch-book11-q090.html https://xdme.com/book11-thumbs/page-090.jpg Why Do Gazelles Stot (Pronk) When Fleeing? Gazelles stot, or pronk, when fleeing because it is a message to the hunter! The bouncy jumps say, I'm healthy and fast, so don't waste your time. Often, the hunter gives up. https://socialmedia.xdme.com/tony/videos-book11/page-090.mp4 https://www.youtube.com/embed/4r6p__VvnGo 111 2026-10-03T04:42:35+00:00 yes https://xdme.com/watch-book11-q091.html https://xdme.com/book11-thumbs/page-091.jpg Why Are Dragonflies Such Good Hunters? Dragonflies are such good hunters because they have big eyes, smart brains, and amazing wings! They catch their prey around 9 times out of 10. That is much better than most hunters https://socialmedia.xdme.com/tony/videos-book11/page-091.mp4 https://www.youtube.com/embed/ol2Z-eVDsTk 115 2026-10-03T04:45:38+00:00 yes https://xdme.com/watch-book11-q092.html https://xdme.com/book11-thumbs/page-092.jpg Why Do Leaf-Tailed Geckos Look Like Dead Leaves? Leaf-tailed geckos look like dead leaves because it helps them hide! They live in the forests of Madagascar. Predators usually pass them by. https://socialmedia.xdme.com/tony/videos-book11/page-092.mp4 https://www.youtube.com/embed/WSXoWQ8m-e0 111 2026-10-03T04:48:50+00:00 yes https://xdme.com/watch-book11-q093.html https://xdme.com/book11-thumbs/page-093.jpg Why Do Remora Fish Stick to Sharks? Remora fish stick to sharks because they get a free ride and a free meal! A remora has a flat sucker on top of its head. It presses the sucker against a big animal and holds on tig https://socialmedia.xdme.com/tony/videos-book11/page-093.mp4 https://www.youtube.com/embed/1fB6_ZD76JE 105 2026-10-03T04:51:23+00:00 yes https://xdme.com/watch-book11-q094.html https://xdme.com/book11-thumbs/page-094.jpg Why Do Vampire Bats Share Blood Meals? Vampire bats share food because sharing keeps the whole roost safe! A bat that cannot find a meal for two nights might get very sick. So the bats that did find food sometimes help https://socialmedia.xdme.com/tony/videos-book11/page-094.mp4 https://www.youtube.com/embed/nruouKlEv9E 110 2026-10-03T04:54:26+00:00 yes https://xdme.com/watch-book11-q095.html https://xdme.com/book11-thumbs/page-095.jpg Do Birds Really Clean Crocodile Teeth? Scientists have almost never seen birds clean crocodile teeth, so the story is mostly a legend! Wild crocodiles are dangerous, so people should always watch them from far away. Don https://socialmedia.xdme.com/tony/videos-book11/page-095.mp4 https://www.youtube.com/embed/_5Pvau9Dd8k 114 2026-10-03T04:57:00+00:00 yes https://xdme.com/watch-book11-q096.html https://xdme.com/book11-thumbs/page-096.jpg Why Do Sea Otters Use Rocks as Tools? Sea otters use rocks as tools because it helps them open hard-shelled food! They eat shellfish like clams and crabs. A rock lets them crack the shells that their teeth can't open. https://socialmedia.xdme.com/tony/videos-book11/page-096.mp4 https://www.youtube.com/embed/89El3uwd80U 114 2026-10-03T05:00:06+00:00 yes https://xdme.com/watch-book11-q097.html https://xdme.com/book11-thumbs/page-097.jpg Why Do Army Ants Swarm? Army ants swarm because together they can do what one ant never could! They march in huge groups through the forest. No single ant is the leader. https://socialmedia.xdme.com/tony/videos-book11/page-097.mp4 https://www.youtube.com/embed/PL4wvr35D1U 108 2026-10-03T05:03:10+00:00 yes https://xdme.com/watch-book11-q098.html https://xdme.com/book11-thumbs/page-098.jpg Why Do Cuttlefish Hypnotize Crabs with Color Waves? Cuttlefish make color waves because the moving patterns can distract a crab! Bands of dark and light ripple across their skin. That gives the cuttlefish time to strike. https://socialmedia.xdme.com/tony/videos-book11/page-098.mp4 https://www.youtube.com/embed/U0DH5tkojnU 115 2026-10-03T05:05:43+00:00 yes https://xdme.com/watch-book11-q099.html https://xdme.com/book11-thumbs/page-099.jpg Why Do Poison Dart Frogs Advertise Bright Colors? Poison dart frogs advertise bright colors because the colors are a warning sign! They say, I taste bad, or I'm toxic, and predators learn to stay away. Never touch a wild frog, and https://socialmedia.xdme.com/tony/videos-book11/page-099.mp4 https://www.youtube.com/embed/NX8xUuDfKN4 119 2026-10-03T05:08:48+00:00 yes https://xdme.com/watch-book11-q100.html https://xdme.com/book11-thumbs/page-100.jpg Why Do Some Animals Help Raise Other Species’ Young (Brood Parasitism)? Some animals help raise other species' young because they get tricked! Cuckoos and cowbirds lay their eggs in other birds' nests. The host parents sit on the egg and feed the chick https://socialmedia.xdme.com/tony/videos-book11/page-100.mp4 https://www.youtube.com/embed/9cBHdzs3WRw 106 2026-10-03T05:11:52+00:00 yes https://xdme.com/watch-book11-q101.html https://xdme.com/book11-thumbs/page-101.jpg Why Do Weaverbirds Weave Hanging Nests? Weaverbirds weave hanging nests because a nest swinging from a thin branch is hard for snakes to reach! The male builds it using only his beak and feet. A sturdy, hidden nest helps https://socialmedia.xdme.com/tony/videos-book11/page-101.mp4 https://www.youtube.com/embed/bnd0T4rlfGo 112 2026-10-03T05:15:07+00:00 yes https://xdme.com/watch-book11-q102.html https://xdme.com/book11-thumbs/page-102.jpg Why Do Birds Choose Different Nest Materials? Birds choose different nest materials because each material does a different job! They use what they can find nearby that keeps eggs safe and snug. So a nest tells you a lot about https://socialmedia.xdme.com/tony/videos-book11/page-102.mp4 https://www.youtube.com/embed/R5QKKVK56As 114 2026-10-03T05:17:41+00:00 yes https://xdme.com/watch-book11-q103.html https://xdme.com/book11-thumbs/page-103.jpg Why Do Termites Build Tall Mounds? Termites build tall mounds because the mounds work like a natural air conditioner! Inside is a maze of tunnels and chimneys. They keep the termites' home fresh and steady, even in https://socialmedia.xdme.com/tony/videos-book11/page-103.mp4 https://www.youtube.com/embed/z_aa8-ge-3E 113 2026-10-03T05:20:49+00:00 yes https://xdme.com/watch-book11-q104.html https://xdme.com/book11-thumbs/page-104.jpg Why Do Burrowing Owls Live Underground? Burrowing owls live underground because it keeps them cool, warm, and safe! They live on grassy prairies where there are very few trees. So they move into holes that other animals https://socialmedia.xdme.com/tony/videos-book11/page-104.mp4 https://www.youtube.com/embed/iusj4LnqlLE 115 2026-10-03T05:23:35+00:00 yes https://xdme.com/watch-book11-q105.html https://xdme.com/book11-thumbs/page-105.jpg Why Do Tailorbirds Sew Leaves Into Nests? Tailorbirds sew leaves into nests so their eggs stay hidden and dry! They live in warm parts of Asia. Using only a beak, they stitch big leaves into a leafy pocket. https://socialmedia.xdme.com/tony/videos-book11/page-105.mp4 https://www.youtube.com/embed/RRAjIfDgKAg 109 2026-10-03T05:26:08+00:00 yes https://xdme.com/watch-book11-q106.html https://xdme.com/book11-thumbs/page-106.jpg Why Do Polar Bears Dig Snow Dens? Polar bears dig snow dens because snow is a great blanket for newborn cubs! Mother bears dig the dens in big snowdrifts, and outside it may be freezing while inside stays much warm https://socialmedia.xdme.com/tony/videos-book11/page-106.mp4 https://www.youtube.com/embed/01K5JAL-FtU 107 2026-10-03T05:28:46+00:00 yes https://xdme.com/watch-book11-q107.html https://xdme.com/book11-thumbs/page-107.jpg Why Do Foxes Dig Dens with More than One Door? Foxes dig dens with more than one door so they always have a way out! A backup exit keeps the fox and her kits safe. Extra doors also let fresh air flow in. https://socialmedia.xdme.com/tony/videos-book11/page-107.mp4 https://www.youtube.com/embed/dl9EGEKdOmg 110 2026-10-03T05:31:57+00:00 yes https://xdme.com/watch-book11-q108.html https://xdme.com/book11-thumbs/page-108.jpg Why Do Wasps Make Paper Nests? Wasps make paper nests because paper is light, strong, and made from things they find! They make the paper themselves. Wasps were making paper long before people were. https://socialmedia.xdme.com/tony/videos-book11/page-108.mp4 https://www.youtube.com/embed/OYeYl1ljKqo 111 2026-10-03T05:34:30+00:00 yes https://xdme.com/watch-book11-q109.html https://xdme.com/book11-thumbs/page-109.jpg Why Do Swallows Build Nests Out of Mud? Swallows build nests out of mud because mud dries hard and sticks to walls! That gives them a strong little cup to raise their chicks. It takes a lot of trips to build one. https://socialmedia.xdme.com/tony/videos-book11/page-109.mp4 https://www.youtube.com/embed/clyu7tzNShU 105 2026-10-03T05:37:02+00:00 yes https://xdme.com/watch-book11-q110.html https://xdme.com/book11-thumbs/page-110.jpg Why Do Squirrels Build Leafy Nests High in Trees? Squirrels build leafy nests high in trees to stay warm, dry, and out of reach! These round nests are called dreys. A drey is like a cozy ball of leaves and twigs in the treetops, w https://socialmedia.xdme.com/tony/videos-book11/page-110.mp4 https://www.youtube.com/embed/p5ALOiw4X1E 106 2026-10-03T05:39:34+00:00 yes https://xdme.com/watch-book11-q111.html https://xdme.com/book11-thumbs/page-111.jpg Why Do Moles Dig Such Long Tunnels? Moles dig long tunnels because the tunnels are both their home and their hunting ground! Worms and insects wander into the tunnels. Then the mole can find them by touch and smell. https://socialmedia.xdme.com/tony/videos-book11/page-111.mp4 https://www.youtube.com/embed/d97ELfSywGs 107 2026-10-03T05:42:38+00:00 yes https://xdme.com/watch-book11-q112.html https://xdme.com/book11-thumbs/page-112.jpg Why Do Eagles Reuse Nests for Years? Eagles reuse nests for years because rebuilding takes huge effort! A good nest in a good spot is worth keeping. So they come back, add sticks, and make it bigger each year. https://socialmedia.xdme.com/tony/videos-book11/page-112.mp4 https://www.youtube.com/embed/biSax9qxhWM 110 2026-10-03T05:45:42+00:00 yes https://xdme.com/watch-book11-q113.html https://xdme.com/book11-thumbs/page-113.jpg Why Do Land Snails Seal Their Shell Doors? Land snails seal their shell doors to keep from drying out! When the weather turns dry or cold, they pull back inside. Then they cover the opening with a layer of dried slime calle https://socialmedia.xdme.com/tony/videos-book11/page-113.mp4 https://www.youtube.com/embed/HmgEkdL4mFo 108 2026-10-03T05:48:21+00:00 yes https://xdme.com/watch-book11-q114.html https://xdme.com/book11-thumbs/page-114.jpg Why Do Bats Roost in Caves? Bats roost in caves because caves are dark, cool, and steady all year! That makes a safe place to sleep during the day. In cold places, bats can even sleep through the winter there https://socialmedia.xdme.com/tony/videos-book11/page-114.mp4 https://www.youtube.com/embed/twIjxjZXsb8 118 2026-10-03T05:50:54+00:00 yes https://xdme.com/watch-book11-q115.html https://xdme.com/book11-thumbs/page-115.jpg Why Do Spiders Choose Corners and Doorways? Spiders choose corners and doorways because that is where insects are likely to pass! A good spot means more food. So the web is a hunting plan, not just a decoration. https://socialmedia.xdme.com/tony/videos-book11/page-115.mp4 https://www.youtube.com/embed/RgZko-7c4d8 115 2026-10-03T05:53:58+00:00 yes https://xdme.com/watch-book11-q116.html https://xdme.com/book11-thumbs/page-116.jpg Why Do Ghost Crabs Dig Burrows on the Beach? Ghost crabs dig burrows on the beach to stay cool, damp, and hidden! The hot sun can dry a crab out. So they hide deep in the sand by day and come out at night. https://socialmedia.xdme.com/tony/videos-book11/page-116.mp4 https://www.youtube.com/embed/5NFen9T5kpY 106 2026-10-03T05:56:29+00:00 yes https://xdme.com/watch-book11-q117.html https://xdme.com/book11-thumbs/page-117.jpg Why Do Flamingos Stand in Shallow Lakes? Flamingos stand in shallow lakes because that is where their food is! They filter tiny shrimp and algae from the water. Long legs let them wade, and few predators can reach them th https://socialmedia.xdme.com/tony/videos-book11/page-117.mp4 https://www.youtube.com/embed/gQO7ZnWKw_U 112 2026-10-03T05:59:34+00:00 yes https://xdme.com/watch-book11-q118.html https://xdme.com/book11-thumbs/page-118.jpg Why Do Urban Foxes Live in Cities? Urban foxes live in cities because cities offer food, shelter, and quiet spots! Red foxes are adaptable, which means they can adjust to new places, and many live in towns across Ca https://socialmedia.xdme.com/tony/videos-book11/page-118.mp4 https://www.youtube.com/embed/R1N8pA3ujD4 117 2026-10-03T06:02:36+00:00 yes https://xdme.com/watch-book11-q119.html https://xdme.com/book11-thumbs/page-119.jpg Why Do Migratory Birds Need Stopover Wetlands? Migratory birds need stopover wetlands because they cannot fly the whole trip without a break! Wetlands are full of food, like insects and seeds. They work like fuel stations on a https://socialmedia.xdme.com/tony/videos-book11/page-119.mp4 https://www.youtube.com/embed/qLZWhERlAq0 114 2026-10-03T06:05:09+00:00 yes https://xdme.com/watch-book11-q120.html https://xdme.com/book11-thumbs/page-120.jpg Why Do Coral Reef Fish Stay Near Home Ranges? Coral reef fish stay near home because knowing a place well helps them survive! They learn where food is and where to hide. That makes escaping danger much quicker. https://socialmedia.xdme.com/tony/videos-book11/page-120.mp4 https://www.youtube.com/embed/giPB4c2FSdA 107 2026-10-03T06:08:11+00:00 yes https://xdme.com/watch-book11-q121.html https://xdme.com/book11-thumbs/page-121.jpg Why Do Bees Build Honeycomb Out of Six-Sided Cells? Bees build honeycomb out of six-sided cells because hexagons are the perfect shape! They fit together with no gaps. That saves wax and space. https://socialmedia.xdme.com/tony/videos-book11/page-121.mp4 https://www.youtube.com/embed/ygp4HWP2cBI 116 2026-10-03T06:10:43+00:00 yes https://xdme.com/watch-book11-q122.html https://xdme.com/book11-thumbs/page-122.jpg Why Do Trapdoor Spiders Live in Burrows with Lids? Trapdoor spiders live in burrows with lids because the lid hides them and keeps the burrow moist! The spider waits in the shadows. From inside, it feels footsteps on the ground. https://socialmedia.xdme.com/tony/videos-book11/page-122.mp4 https://www.youtube.com/embed/ilyacpoIKbg 110 2026-10-03T06:13:16+00:00 yes https://xdme.com/watch-book11-q123.html https://xdme.com/book11-thumbs/page-123.jpg Why Do Woodpeckers Carve Nest Holes in Trees? Woodpeckers carve nest holes in trees because a hole in a trunk is a safe, dry home! It keeps eggs away from most predators. And old holes help other animals, too. https://socialmedia.xdme.com/tony/videos-book11/page-123.mp4 https://www.youtube.com/embed/rj7NeciH0vI 111 2026-10-03T06:15:49+00:00 yes https://xdme.com/watch-book11-q124.html https://xdme.com/book11-thumbs/page-124.jpg Why Do Tree Frogs Need Moist Micro-Homes? Tree frogs need moist micro-homes because their thin skin dries out fast! A micro-home is a tiny damp hideout, like a leaf pocket or a hollow in a tree. They find places high in th https://socialmedia.xdme.com/tony/videos-book11/page-124.mp4 https://www.youtube.com/embed/sLsNfFSzgUk 113 2026-10-03T06:18:52+00:00 yes https://xdme.com/watch-book11-q125.html https://xdme.com/book11-thumbs/page-125.jpg Why Do Animals Share Habitats Without Always Fighting? Animals can share habitats without always fighting because they use different parts or times of it! That way they don't compete as much. Scientists call this niche partitioning. https://socialmedia.xdme.com/tony/videos-book11/page-125.mp4 https://www.youtube.com/embed/3TSiNebhcqI 114 2026-10-03T06:21:39+00:00 yes https://xdme.com/watch-book11-q126.html https://xdme.com/book11-thumbs/page-126.jpg Why Is a Giraffe’s Neck So Long? A giraffe's neck is so long because it helps the giraffe reach leaves high up in trees! Few other animals can eat up there, so the giraffe does not have to share. That means plenty https://socialmedia.xdme.com/tony/videos-book11/page-126.mp4 https://www.youtube.com/embed/BbBgfM_XHNs 108 2026-10-03T06:23:42+00:00 yes https://xdme.com/watch-book11-q127.html https://xdme.com/book11-thumbs/page-127.jpg Why Can Peregrine Falcons Dive So Fast? Peregrine falcons can dive so fast because they use gravity and a perfect shape! They climb high first, then fold their wings. They can go over 300 kilometers an hour, the fastest https://socialmedia.xdme.com/tony/videos-book11/page-127.mp4 https://www.youtube.com/embed/cMDYRVqhAPY 116 2026-10-03T06:26:15+00:00 yes https://xdme.com/watch-book11-q128.html https://xdme.com/book11-thumbs/page-128.jpg Why Can a Mantis Shrimp Punch So Fast? A mantis shrimp can punch so fast because its arm works like a spring-loaded hammer! The club is held back by a latch, then released. It swings out in a flash. https://socialmedia.xdme.com/tony/videos-book11/page-128.mp4 https://www.youtube.com/embed/_U87oLQM9H8 107 2026-10-03T06:28:47+00:00 yes https://xdme.com/watch-book11-q129.html https://xdme.com/book11-thumbs/page-129.jpg Why Is a Cheetah the Land Sprint King? A cheetah is the land sprint king because its body is built for speed! It can run up to about 100 kilometers an hour. It can only keep that speed up for short bursts before it need https://socialmedia.xdme.com/tony/videos-book11/page-129.mp4 https://www.youtube.com/embed/-ZhayuI-K6g 109 2026-10-03T06:31:31+00:00 yes https://xdme.com/watch-book11-q130.html https://xdme.com/book11-thumbs/page-130.jpg Why Can Archerfish Shoot Water at Bugs? Archerfish can shoot water at bugs because they have a built-in squirt gun! They spit a strong jet of water at insects on leaves above. The bug falls into the water, and the fish e https://socialmedia.xdme.com/tony/videos-book11/page-130.mp4 https://www.youtube.com/embed/uIxqN9KdilA 110 2026-10-03T06:34:05+00:00 yes https://xdme.com/watch-book11-q131.html https://xdme.com/book11-thumbs/page-131.jpg Why Do Tardigrades Survive Extreme Conditions? Tardigrades survive extreme conditions because they can dry up and pause their bodies! These tiny animals look like chubby bears with eight legs. They wake up again when water retu https://socialmedia.xdme.com/tony/videos-book11/page-131.mp4 https://www.youtube.com/embed/SLLCkomNjN0 110 2026-10-03T06:36:40+00:00 yes https://xdme.com/watch-book11-q132.html https://xdme.com/book11-thumbs/page-132.jpg Why Can Some Animals Live for Hundreds of Years? A few animals, like the Greenland shark and the ocean quahog clam, can live for hundreds of years! They live in cold water, where their bodies work slowly and age slowly. Scientist https://socialmedia.xdme.com/tony/videos-book11/page-132.mp4 https://www.youtube.com/embed/FHNPNO3QU3k 114 2026-10-03T06:39:43+00:00 yes https://xdme.com/watch-book11-q133.html https://xdme.com/book11-thumbs/page-133.jpg Why Do Tiny Shrews Have to Eat Almost All Day? Tiny shrews eat almost all day because their little bodies burn energy super fast! A shrew is one of the smallest mammals, with a pointy nose and tiny eyes. Small bodies lose heat https://socialmedia.xdme.com/tony/videos-book11/page-133.mp4 https://www.youtube.com/embed/vPKQPxZsYJM 110 2026-10-03T06:42:16+00:00 yes https://xdme.com/watch-book11-q134.html https://xdme.com/book11-thumbs/page-134.jpg Why Do Wood Frogs Freeze in Winter and Thaw? Wood frogs freeze in winter and thaw in spring because sugars in their bodies work like antifreeze! Their hearts stop beating and ice forms around their cells, but they wake up aga https://socialmedia.xdme.com/tony/videos-book11/page-134.mp4 https://www.youtube.com/embed/LQQ7SdJz7Io 111 2026-10-03T06:44:48+00:00 yes https://xdme.com/watch-book11-q135.html https://xdme.com/book11-thumbs/page-135.jpg Why Do Sperm Whales Dive So Deep? Sperm whales dive so deep because their favorite food lives in the dark depths! They can dive over a thousand meters. Their bodies are built to handle it. https://socialmedia.xdme.com/tony/videos-book11/page-135.mp4 https://www.youtube.com/embed/WjYM1M6Gs9U 112 2026-10-03T06:47:22+00:00 yes https://xdme.com/watch-book11-q136.html https://xdme.com/book11-thumbs/page-136.jpg How Do Scientists Recognize Individual Animals From Their Spots and Stripes? Scientists can recognize individual animals because many animals have patterns that are one of a kind! Spots, stripes, and scars work like fingerprints. That way, researchers can f https://socialmedia.xdme.com/tony/videos-book11/page-136.mp4 https://www.youtube.com/embed/8aDydepQUis 122 2026-10-03T06:49:54+00:00 yes https://xdme.com/watch-book11-q137.html https://xdme.com/book11-thumbs/page-137.jpg Why Do Wildlife Corridors Matter? Wildlife corridors matter because roads split habitats into pieces! Animals that try to cross busy roads are in danger. Corridors give them safe paths to cross. https://socialmedia.xdme.com/tony/videos-book11/page-137.mp4 https://www.youtube.com/embed/PBGvVdQk7TM 118 2026-10-03T06:52:26+00:00 yes https://xdme.com/watch-book11-q138.html https://xdme.com/book11-thumbs/page-138.jpg Why Do Rehab Centers Help Injured Animals? Rehab centers help injured animals because wild animals need trained care! Wildlife rehabilitators look after hurt or orphaned wild animals and then release them back to the wild w https://socialmedia.xdme.com/tony/videos-book11/page-138.mp4 https://www.youtube.com/embed/5H9qt8sZ5nk 116 2026-10-03T06:55:30+00:00 yes https://xdme.com/watch-book11-q139.html https://xdme.com/book11-thumbs/page-139.jpg Why Should You Never “Rescue” a Fawn Alone? You should never rescue a fawn alone because it is usually not abandoned! A mother deer often leaves her fawn hidden for hours while she feeds nearby. The kind choice is to leave i https://socialmedia.xdme.com/tony/videos-book11/page-139.mp4 https://www.youtube.com/embed/1Bz7v4VygQc 111 2026-10-03T06:58:03+00:00 yes https://xdme.com/watch-book11-q140.html https://xdme.com/book11-thumbs/page-140.jpg Why Do Bird Windows Need Stickers? Bird windows need stickers because birds cannot tell that glass is solid! Glass can reflect trees and sky, or look like an open path. Stickers help birds see a barrier. https://socialmedia.xdme.com/tony/videos-book11/page-140.mp4 https://www.youtube.com/embed/IVCyIJtiQEM 111 2026-10-03T07:00:44+00:00 yes https://xdme.com/watch-book11-q141.html https://xdme.com/book11-thumbs/page-141.jpg Why Do Bat Houses and Nest Boxes Help Wildlife? Bat houses and nest boxes help wildlife because safe homes are getting harder to find! Old hollow trees are getting rarer. So people put up boxes that are dry, safe, and the right https://socialmedia.xdme.com/tony/videos-book11/page-141.mp4 https://www.youtube.com/embed/-eb5IpGq7s4 110 2026-10-03T07:03:20+00:00 yes https://xdme.com/watch-book11-q142.html https://xdme.com/book11-thumbs/page-142.jpg Why Do Zoos Run Breeding Programs? Zoos run breeding programs to help endangered animals survive! Zoos work together to keep track of each animal's family. That keeps the animal group healthy and varied. https://socialmedia.xdme.com/tony/videos-book11/page-142.mp4 https://www.youtube.com/embed/5frB0e1JiH8 121 2026-10-03T07:05:53+00:00 yes https://xdme.com/watch-book11-q143.html https://xdme.com/book11-thumbs/page-143.jpg Why Do Citizen Scientists Count Butterflies? Citizen scientists count butterflies to help real scientists learn! Citizen scientists are volunteers who collect information, and you can be one! One person cannot count everywher https://socialmedia.xdme.com/tony/videos-book11/page-143.mp4 https://www.youtube.com/embed/xaNRmU1OfZ0 120 2026-10-03T07:08:56+00:00 yes https://xdme.com/watch-book11-q144.html https://xdme.com/book11-thumbs/page-144.jpg Why Do Quiet Zones Help Nesting Birds? Quiet zones help nesting birds because noise and surprises can scare them off their nests! Birds nest on the ground or in shrubs. Quiet and space let them raise their chicks. https://socialmedia.xdme.com/tony/videos-book11/page-144.mp4 https://www.youtube.com/embed/VQUGuDTEW_U 111 2026-10-03T07:11:31+00:00 yes https://xdme.com/watch-book11-q145.html https://xdme.com/book11-thumbs/page-145.jpg Why Do Some Animals Sleep with Half Their Brain Awake? Some animals sleep with half their brain awake so they can rest and stay safe at the same time! Dolphins and some birds can do this. One half rests while the other half keeps watch https://socialmedia.xdme.com/tony/videos-book11/page-145.mp4 https://www.youtube.com/embed/21_DT3GwYOc 104 2026-10-03T07:14:03+00:00 yes https://xdme.com/watch-book11-q146.html https://xdme.com/book11-thumbs/page-146.jpg Why Do Researchers Use Camera Traps? Researchers use camera traps to see animals that stay away from people! A camera trap takes a picture when it senses movement or warmth. It lets scientists watch without disturbing https://socialmedia.xdme.com/tony/videos-book11/page-146.mp4 https://www.youtube.com/embed/IRKRkTWoLn4 112 2026-10-03T07:17:08+00:00 yes https://xdme.com/watch-book11-q147.html https://xdme.com/book11-thumbs/page-147.jpg Why Is Habitat the Best “Rescue”? Habitat is the best rescue because protecting a home helps many animals at once! Rescuing one injured animal helps just that one. Protecting the places where animals live helps tho https://socialmedia.xdme.com/tony/videos-book11/page-147.mp4 https://www.youtube.com/embed/QFP_2Z5S4EE 118 2026-10-03T07:19:49+00:00 yes https://xdme.com/watch-book11-q148.html https://xdme.com/book11-thumbs/page-148.jpg Why Can a Flea Jump So High? A flea can jump so high because its legs have a tiny built-in spring! The spring is made of a rubbery protein called resilin. It stores energy and then lets it out all at once. https://socialmedia.xdme.com/tony/videos-book11/page-148.mp4 https://www.youtube.com/embed/mQtGfN3eBQA 107 2026-10-03T07:22:21+00:00 yes https://xdme.com/watch-book11-q149.html https://xdme.com/book11-thumbs/page-149.jpg Why Should Curiosity Stay Kind? Curiosity should stay kind because wild animals need space to stay safe! Watching from a distance and never chasing or touching them helps animals and lets you learn more. Kind cur https://socialmedia.xdme.com/tony/videos-book11/page-149.mp4 https://www.youtube.com/embed/Vblzcq9Zs3k 115 2026-10-03T07:24:56+00:00 yes https://xdme.com/watch-book11-q150.html https://xdme.com/book11-thumbs/page-150.jpg Why Do Scientists Still Discover New Animal Species Every Year? Scientists still discover new animal species every year because Earth is huge and full of tiny, hidden animals! Most places have never been searched closely. Only a fraction of Ear https://socialmedia.xdme.com/tony/videos-book11/page-150.mp4 https://www.youtube.com/embed/yZSxU8_2mHM 117 2026-10-03T07:28:12+00:00 yes https://xdme.com/watch-book12-q001.html https://xdme.com/book12-thumbs/page-001.jpg Why Is Earth’s Inside So Hot? Earth's inside is hot for two reasons: leftover heat, and new heat that rocks keep making! It gets hotter the farther down you go. The center of Earth is about as hot as the surfac https://socialmedia.xdme.com/tony/videos-book12/page-001.mp4 https://www.youtube.com/embed/MJw0-NDg-2w 116 2026-10-03T08:07:30+00:00 yes https://xdme.com/watch-book12-q002.html https://xdme.com/book12-thumbs/page-002.jpg How Can Scientists Tell Whether a Rock Was Once Magma or Lava? Rocks keep clues about how they cooled! Magma that cools slowly underground grows big crystals. Lava that cools quickly outside makes tiny crystals, or even glass. https://socialmedia.xdme.com/tony/videos-book12/page-002.mp4 https://www.youtube.com/embed/gBa6vw56knw 123 2026-10-03T08:07:31+00:00 yes https://xdme.com/watch-book12-q003.html https://xdme.com/book12-thumbs/page-003.jpg Why Does Lava Glow? Anything extremely hot gives off light, and lava is extremely hot! The hotter it is, the brighter and yellower the glow. Lava is dangerous, so people watch it only from far away. https://socialmedia.xdme.com/tony/videos-book12/page-003.mp4 https://www.youtube.com/embed/_LYwy36tTsA 114 2026-10-03T08:07:32+00:00 yes https://xdme.com/watch-book12-q004.html https://xdme.com/book12-thumbs/page-004.jpg Why Does Some Lava Move Fast and Some Crawl? Lava speed depends on how runny it is! Runny lava can race downhill, while thick lava barely creeps. Either kind is dangerously hot, so people stay far away from lava and follow lo https://socialmedia.xdme.com/tony/videos-book12/page-004.mp4 https://www.youtube.com/embed/RW766SOSncI 112 2026-10-03T08:07:33+00:00 yes https://xdme.com/watch-book12-q005.html https://xdme.com/book12-thumbs/page-005.jpg Why Does Pahoehoe Lava Look Ropy? Pahoehoe is a Hawaiian word for smooth, ropy lava. Its surface cools into a thin skin that wrinkles into twisted ropes while the lava underneath keeps moving. Real lava is dangerou https://socialmedia.xdme.com/tony/videos-book12/page-005.mp4 https://www.youtube.com/embed/_NiRP0TcCQQ 113 2026-10-03T08:07:35+00:00 yes https://xdme.com/watch-book12-q006.html https://xdme.com/book12-thumbs/page-006.jpg Why Does Aa Lava Look Spiky? Aa lava is thick, sticky lava that breaks into rough, sharp chunks as it creeps forward. It is spiky because it cracks while it is still moving, which makes the ground very rough. https://socialmedia.xdme.com/tony/videos-book12/page-006.mp4 https://www.youtube.com/embed/kPL9EuAlVI4 114 2026-10-03T08:07:36+00:00 yes https://xdme.com/watch-book12-q007.html https://xdme.com/book12-thumbs/page-007.jpg Why Do Lava Tubes Form? A lava tube is an empty tunnel left behind by a river of lava. The top of the river cools into a roof, while the hot lava keeps flowing below. When the lava drains away, the tunnel https://socialmedia.xdme.com/tony/videos-book12/page-007.mp4 https://www.youtube.com/embed/ff0XhgY3DtA 106 2026-10-03T08:07:38+00:00 yes https://xdme.com/watch-book12-q008.html https://xdme.com/book12-thumbs/page-008.jpg What Is a Caldera? A caldera is a huge bowl-shaped hollow in the ground. It forms when a volcano empties its magma so fast that the ground above collapses. Calderas can be many kilometers wide! https://socialmedia.xdme.com/tony/videos-book12/page-008.mp4 https://www.youtube.com/embed/6x2-fqUOBjA 113 2026-10-03T08:07:39+00:00 yes https://xdme.com/watch-book12-q009.html https://xdme.com/book12-thumbs/page-009.jpg Why Do Eruptions Make Tall Umbrella-Shaped Ash Clouds? Big eruptions blast hot gas and ash high into the sky. The cloud rises because it is hotter and lighter than the air around it, then spreads out at the top like an umbrella! Ash cl https://socialmedia.xdme.com/tony/videos-book12/page-009.mp4 https://www.youtube.com/embed/GNbcxr3rh9E 107 2026-10-03T08:08:59+00:00 yes https://xdme.com/watch-book12-q010.html https://xdme.com/book12-thumbs/page-010.jpg What Is Pumice, the Rock Full of Bubbles? Pumice is a rock so full of bubble holes that it is mostly air. It forms when frothy lava cools quickly and the gas bubbles get trapped. It is so light that it floats on water! https://socialmedia.xdme.com/tony/videos-book12/page-010.mp4 https://www.youtube.com/embed/7dyyZcNgJOc 110 2026-10-03T08:11:32+00:00 yes https://xdme.com/watch-book12-q011.html https://xdme.com/book12-thumbs/page-011.jpg Why Is Obsidian So Glassy? Obsidian is natural glass made by volcanoes! It forms when lava cools so fast that crystals do not have time to grow. That makes it smooth and shiny all the way through. https://socialmedia.xdme.com/tony/videos-book12/page-011.mp4 https://www.youtube.com/embed/oFoJk3qFxGk 113 2026-10-03T08:14:37+00:00 yes https://xdme.com/watch-book12-q012.html https://xdme.com/book12-thumbs/page-012.jpg Why Do Volcanoes Smell Like Rotten Eggs Sometimes? Many volcanoes release gases with sulfur in them, and one of them, hydrogen sulfide, smells like rotten eggs. Our noses can notice it even in tiny amounts. Volcanic gases can be ha https://socialmedia.xdme.com/tony/videos-book12/page-012.mp4 https://www.youtube.com/embed/ceDJiIns8Fc 115 2026-10-03T08:17:10+00:00 yes https://xdme.com/watch-book12-q013.html https://xdme.com/book12-thumbs/page-013.jpg Why Does Lava Harden Into Different Rocks? Lava hardens into different rocks depending on two things: what the lava is made of and how fast it cools. Think of it like baking, where ingredients and time both matter. Slower c https://socialmedia.xdme.com/tony/videos-book12/page-013.mp4 https://www.youtube.com/embed/dNhrF-9iMT8 120 2026-10-03T08:20:16+00:00 yes https://xdme.com/watch-book12-q014.html https://xdme.com/book12-thumbs/page-014.jpg Why Do Cinder Cones Look Like Sand Piles? A cinder cone is a small, steep volcano built from bits of lava. The bits shoot up, fall back down, and pile up around the vent. Just like a pile of sand, the loose bits settle int https://socialmedia.xdme.com/tony/videos-book12/page-014.mp4 https://www.youtube.com/embed/ZauNSkpJ5rU 109 2026-10-03T08:22:49+00:00 yes https://xdme.com/watch-book12-q015.html https://xdme.com/book12-thumbs/page-015.jpg What Makes a Volcano Go Dormant or Extinct? Scientists sort volcanoes into three groups: active, dormant, and extinct. Each group tells us how likely a volcano is to erupt, and scientists decide using many clues. Even a slee https://socialmedia.xdme.com/tony/videos-book12/page-015.mp4 https://www.youtube.com/embed/6krUmdilLpQ 118 2026-10-03T08:25:27+00:00 yes https://xdme.com/watch-book12-q016.html https://xdme.com/book12-thumbs/page-016.jpg What Was the Biggest Eruption People Have Ever Recorded? In 1815, Mount Tambora in Indonesia had the biggest eruption in recorded history. It blasted so much ash and gas into the sky that it cooled the weather around the world. Scientist https://socialmedia.xdme.com/tony/videos-book12/page-016.mp4 https://www.youtube.com/embed/iumEMCWWZwI 125 2026-10-03T08:28:31+00:00 yes https://xdme.com/watch-book12-q017.html https://xdme.com/book12-thumbs/page-017.jpg Why Is Magma Full of Bubbles? Magma has gases dissolved in it, like the fizz in soda. Deep underground, huge pressure keeps the gas squeezed inside, just like in a sealed soda bottle. As magma rises, the pressu https://socialmedia.xdme.com/tony/videos-book12/page-017.mp4 https://www.youtube.com/embed/NIXRdobAtOI 112 2026-10-03T08:34:03+00:00 yes https://xdme.com/watch-book12-q018.html https://xdme.com/book12-thumbs/page-018.jpg How Do Geologists Measure How Big an Eruption Is? Geologists rate eruptions with the Volcanic Explosivity Index. It is a scale from 0 to 8, mostly based on how much material was thrown out and how high the plume rose. Each step is https://socialmedia.xdme.com/tony/videos-book12/page-018.mp4 https://www.youtube.com/embed/9NBqUkTm_Ds 109 2026-10-03T08:37:06+00:00 yes https://xdme.com/watch-book12-q019.html https://xdme.com/book12-thumbs/page-019.jpg Why Does Lava Crust Over While Still Moving? When lava meets the air, the outside cools fast and hardens into a crust. The inside stays glowing hot and keeps moving underneath, like a blanket of rock over a hot river. That is https://socialmedia.xdme.com/tony/videos-book12/page-019.mp4 https://www.youtube.com/embed/pF1RRVSjnxg 112 2026-10-03T08:39:39+00:00 yes https://xdme.com/watch-book12-q020.html https://xdme.com/book12-thumbs/page-020.jpg Why Do Volcanoes Make Lightning in Ash Clouds? Inside a big ash cloud, bits of ash and ice bump into each other. The rubbing builds up electric charge, just like static electricity. Then a giant spark jumps through the cloud as https://socialmedia.xdme.com/tony/videos-book12/page-020.mp4 https://www.youtube.com/embed/ofnvcmYW7Jw 117 2026-10-03T08:42:42+00:00 yes https://xdme.com/watch-book12-q021.html https://xdme.com/book12-thumbs/page-021.jpg Why Is Fresh Lava Dangerous Long After It Stops Glowing? Fresh lava can look dark and solid after the top cools, but a thick crust can hide very hot rock underneath. That is why people stay far away from new lava, even when nothing glows https://socialmedia.xdme.com/tony/videos-book12/page-021.mp4 https://www.youtube.com/embed/9DD0lbX8KPo 112 2026-10-03T08:45:44+00:00 yes https://xdme.com/watch-book12-q022.html https://xdme.com/book12-thumbs/page-022.jpg Why Do Scientists Wear Special Suits Near Lava? Volcano scientists sometimes wear silvery suits near lava that reflect heat. The suits protect them for only a short time, so scientists plan very carefully. These are trained expe https://socialmedia.xdme.com/tony/videos-book12/page-022.mp4 https://www.youtube.com/embed/VPx_IM4rcE4 114 2026-10-03T08:48:18+00:00 yes https://xdme.com/watch-book12-q023.html https://xdme.com/book12-thumbs/page-023.jpg Why Does Cooling Lava Crack? As lava cools, it shrinks. When rock shrinks, it pulls apart and cracks, a bit like mud drying in the Sun. In thick flows, those cracks can make six-sided columns! https://socialmedia.xdme.com/tony/videos-book12/page-023.mp4 https://www.youtube.com/embed/s-9_o97uEac 108 2026-10-03T08:51:21+00:00 yes https://xdme.com/watch-book12-q024.html https://xdme.com/book12-thumbs/page-024.jpg Why Do Volcanic Bombs Exist? A volcanic bomb is a blob of melted lava thrown out of a volcano. It cools and hardens as it flies through the air, so the outside is solid when it lands, even if the inside is sti https://socialmedia.xdme.com/tony/videos-book12/page-024.mp4 https://www.youtube.com/embed/bSGmPEaTiLQ 106 2026-10-03T08:56:31+00:00 yes https://xdme.com/watch-book12-q025.html https://xdme.com/book12-thumbs/page-025.jpg Why Do People Study Ash Layers in Soil? Every eruption can spread a thin layer of ash over a huge area. The ash gets buried in soil, lakes, and ice. Scientists dig it up to read the story of the past, layer by layer. https://socialmedia.xdme.com/tony/videos-book12/page-025.mp4 https://www.youtube.com/embed/HBlk_8f8kqg 112 2026-10-03T08:59:34+00:00 yes https://xdme.com/watch-book12-q026.html https://xdme.com/book12-thumbs/page-026.jpg Why Does Earth Have Thousands of Tiny Earthquakes Every Day That We Never Feel? Earth is shaking all the time, but most of it is far too small to feel! Instruments detect around half a million small earthquakes every year. That is more than a thousand every da https://socialmedia.xdme.com/tony/videos-book12/page-026.mp4 https://www.youtube.com/embed/QbWf5GAa1Aw 109 2026-10-03T09:02:36+00:00 yes https://xdme.com/watch-book12-q027.html https://xdme.com/book12-thumbs/page-027.jpg Why Does the Ground Wave in a Quake? An earthquake sends out waves, just like a pebble makes ripples in a pond. Different waves move the ground in different ways. The waves travel through the ground, but the ground it https://socialmedia.xdme.com/tony/videos-book12/page-027.mp4 https://www.youtube.com/embed/MhJxNI9ZJBM 108 2026-10-03T09:05:09+00:00 yes https://xdme.com/watch-book12-q028.html https://xdme.com/book12-thumbs/page-028.jpg How Do We Measure How Strong an Earthquake Is? Earthquake strength is measured with a number called magnitude. The scale most scientists use today is called moment magnitude. It replaced the older Richter scale, which worked be https://socialmedia.xdme.com/tony/videos-book12/page-028.mp4 https://www.youtube.com/embed/par4aq50yXo 118 2026-10-03T09:08:12+00:00 yes https://xdme.com/watch-book12-q029.html https://xdme.com/book12-thumbs/page-029.jpg Why Do We Feel Aftershocks? After a big earthquake, the rock around the fault needs time to settle. That settling causes more, smaller earthquakes called aftershocks. They are usually weaker than the first qu https://socialmedia.xdme.com/tony/videos-book12/page-029.mp4 https://www.youtube.com/embed/vuXbhH1MepU 112 2026-10-03T09:10:44+00:00 yes https://xdme.com/watch-book12-q030.html https://xdme.com/book12-thumbs/page-030.jpg Why Do Seismographs Draw Squiggles? A seismograph has a heavy weight that tries to stay still. When the ground shakes, the frame moves, but the weight does not. A pen draws the difference as a squiggly line. https://socialmedia.xdme.com/tony/videos-book12/page-030.mp4 https://www.youtube.com/embed/w_veiQhVAhg 107 2026-10-03T09:13:18+00:00 yes https://xdme.com/watch-book12-q031.html https://xdme.com/book12-thumbs/page-031.jpg Why Can Sensors Feel Earthquakes That People Can’t? Sensors can measure ground movements thousands of times smaller than anything a person can feel. Our bodies only notice shaking that is big enough to move us. Machines extend our s https://socialmedia.xdme.com/tony/videos-book12/page-031.mp4 https://www.youtube.com/embed/HsqyuUf7ya4 112 2026-10-03T09:16:37+00:00 yes https://xdme.com/watch-book12-q032.html https://xdme.com/book12-thumbs/page-032.jpg Why Does Shaking Feel Worse on Soft Soil? Soft, loose ground shakes more, and for longer, than hard rock. Think of a bowl of jelly wobbling on a table. Hard rock is more like a block of wood. https://socialmedia.xdme.com/tony/videos-book12/page-032.mp4 https://www.youtube.com/embed/Wnzjb8ZNUhQ 113 2026-10-03T09:19:10+00:00 yes https://xdme.com/watch-book12-q033.html https://xdme.com/book12-thumbs/page-033.jpg Why Do Buildings Get Special Earthquake Designs? Engineers design buildings to move instead of break. A building that can sway a little is safer than one that is stiff and brittle, like a tree in the wind. Bending is better than https://socialmedia.xdme.com/tony/videos-book12/page-033.mp4 https://www.youtube.com/embed/SVpGwth1DuY 115 2026-10-03T09:22:14+00:00 yes https://xdme.com/watch-book12-q034.html https://xdme.com/book12-thumbs/page-034.jpg Why Should You Drop, Cover, and Hold On? When the ground shakes strongly, the safest plan is easy to remember: drop, cover, and hold on. Each step protects you in a different way. Practicing makes it automatic, so you can https://socialmedia.xdme.com/tony/videos-book12/page-034.mp4 https://www.youtube.com/embed/hapw9t6nRh8 110 2026-10-03T09:24:46+00:00 yes https://xdme.com/watch-book12-q035.html https://xdme.com/book12-thumbs/page-035.jpg Why Do Tsunamis Follow Some Undersea Quakes? Most tsunamis start when part of the seafloor suddenly jerks up or down in a big earthquake. That pushes the whole column of water above it, and waves spread out in all directions. https://socialmedia.xdme.com/tony/videos-book12/page-035.mp4 https://www.youtube.com/embed/4t5YmAK2bh0 109 2026-10-03T09:27:19+00:00 yes https://xdme.com/watch-book12-q036.html https://xdme.com/book12-thumbs/page-036.jpg Why Is “Tidal Wave” a Misleading Name? A tsunami has nothing to do with the tides. The word comes from Japanese and means harbor wave. Using the right word helps people understand what is happening, and what to do. https://socialmedia.xdme.com/tony/videos-book12/page-036.mp4 https://www.youtube.com/embed/q1C7neGO-nA 110 2026-10-03T09:30:22+00:00 yes https://xdme.com/watch-book12-q037.html https://xdme.com/book12-thumbs/page-037.jpg Why Do Animals Sometimes Act Odd Before Quakes? People have noticed that pets and wildlife sometimes act strangely before a quake, but scientists have not found a reliable pattern. Animals may react to many things, so their beha https://socialmedia.xdme.com/tony/videos-book12/page-037.mp4 https://www.youtube.com/embed/Q8PvTBFaCqs 124 2026-10-03T09:33:25+00:00 yes https://xdme.com/watch-book12-q038.html https://xdme.com/book12-thumbs/page-038.jpg Why Can’t We Predict Exact Quake Times Yet? Earthquakes start deep underground, where we cannot watch them. Scientists can say how likely a quake is over decades, but not the exact day. Forecasts talk about chances, like the https://socialmedia.xdme.com/tony/videos-book12/page-038.mp4 https://www.youtube.com/embed/urJu78OPxCQ 115 2026-10-03T09:35:56+00:00 yes https://xdme.com/watch-book12-q039.html https://xdme.com/book12-thumbs/page-039.jpg Why Do Transform Faults Slide Sideways? At a transform fault, two plates slide past each other sideways. They snag and stick, and the stress builds up. Then they suddenly slip, and that makes an earthquake! https://socialmedia.xdme.com/tony/videos-book12/page-039.mp4 https://www.youtube.com/embed/P-S--Xi41DU 115 2026-10-03T09:38:29+00:00 yes https://xdme.com/watch-book12-q040.html https://xdme.com/book12-thumbs/page-040.jpg Why Do Normal Faults Drop Blocks Down? Where Earth's crust is being pulled apart, a block of rock can slip down along a steep crack. That crack is called a normal fault. Normal does not mean usual. https://socialmedia.xdme.com/tony/videos-book12/page-040.mp4 https://www.youtube.com/embed/y7Ifj832eZQ 110 2026-10-03T09:41:02+00:00 yes https://xdme.com/watch-book12-q041.html https://xdme.com/book12-thumbs/page-041.jpg Why Do Reverse Faults Shove Rock Up? In a reverse fault, rocks are squeezed together, and one block is pushed up over the other, like a rug that bunches up. This happens where plates push into each other. Over million https://socialmedia.xdme.com/tony/videos-book12/page-041.mp4 https://www.youtube.com/embed/gBAgCDBPOAA 110 2026-10-03T09:43:36+00:00 yes https://xdme.com/watch-book12-q042.html https://xdme.com/book12-thumbs/page-042.jpg Why Is the “Ring of Fire” So Quake-Y? The Ring of Fire is a horseshoe-shaped belt around the Pacific Ocean. Many plates meet there, so it has lots of earthquakes and volcanoes. About 90 percent of the world's earthquak https://socialmedia.xdme.com/tony/videos-book12/page-042.mp4 https://www.youtube.com/embed/tT7dQfiawIE 111 2026-10-03T09:47:08+00:00 yes https://xdme.com/watch-book12-q043.html https://xdme.com/book12-thumbs/page-043.jpg Can People Cause Small Earthquakes? Yes, sometimes people can cause small earthquakes. Anything that changes the pressure deep underground can nudge a fault. But natural quakes are far more common and bigger. https://socialmedia.xdme.com/tony/videos-book12/page-043.mp4 https://www.youtube.com/embed/FRURfKeRylU 112 2026-10-03T09:49:41+00:00 yes https://xdme.com/watch-book12-q044.html https://xdme.com/book12-thumbs/page-044.jpg Why Do Old Brick Buildings Crack in Earthquakes While Wooden Houses Bend? Old brick buildings are stiff and brittle, which means they crack instead of bend. Wood-framed houses can bend and flex, like a diving board. Flexible things are often stronger in https://socialmedia.xdme.com/tony/videos-book12/page-044.mp4 https://www.youtube.com/embed/_CGE7HQ2u_A 114 2026-10-03T09:55:36+00:00 yes https://xdme.com/watch-book12-q045.html https://xdme.com/book12-thumbs/page-045.jpg Why Do Bridges Need Expansion and Motion Joints? Bridges grow longer in hot weather and shorter in cold weather. They also shake from wind, traffic, and earthquakes. Gaps called expansion joints give them room to move. https://socialmedia.xdme.com/tony/videos-book12/page-045.mp4 https://www.youtube.com/embed/Nyj6TZxP5l8 110 2026-10-03T09:58:09+00:00 yes https://xdme.com/watch-book12-q046.html https://xdme.com/book12-thumbs/page-046.jpg Why Do Emergency Kits Include Shoes By the Bed? After an earthquake, the floor can be covered with broken glass and sharp bits. Sturdy shoes by your bed protect your feet. A flashlight helps you see if the power goes out. https://socialmedia.xdme.com/tony/videos-book12/page-046.mp4 https://www.youtube.com/embed/jhjueHenfN8 107 2026-10-03T10:01:12+00:00 yes https://xdme.com/watch-book12-q047.html https://xdme.com/book12-thumbs/page-047.jpg Why Do Grown-Ups Learn Where the Gas Shutoff Is? After a strong earthquake, pipes can crack and gas can leak. That is why grown-ups learn where the gas shutoff is. Only a grown-up who has been shown how should use it. https://socialmedia.xdme.com/tony/videos-book12/page-047.mp4 https://www.youtube.com/embed/y4bHDn1xNPI 105 2026-10-03T10:03:44+00:00 yes https://xdme.com/watch-book12-q048.html https://xdme.com/book12-thumbs/page-048.jpg Why Are Some Earthquakes Deep Underground and Others Close to the Surface? Some earthquakes start deep underground, and others start close to the surface. The place where the rock first slips is called the focus. Its depth changes how the shaking feels at https://socialmedia.xdme.com/tony/videos-book12/page-048.mp4 https://www.youtube.com/embed/8RBXOhU8syE 113 2026-10-03T10:06:48+00:00 yes https://xdme.com/watch-book12-q049.html https://xdme.com/book12-thumbs/page-049.jpg Why Can Distant Quakes Still Make Chandeliers Wobble? Earthquake waves can travel very far through the ground. They get weaker as they spread out, like ripples in a pond. But strong ones can still reach places hundreds, or even thousa https://socialmedia.xdme.com/tony/videos-book12/page-049.mp4 https://www.youtube.com/embed/fPzinG3mWFg 109 2026-10-03T10:09:50+00:00 yes https://xdme.com/watch-book12-q050.html https://xdme.com/book12-thumbs/page-050.jpg Why Do Scientists Love GPS for Quakes? GPS stations sit on solid rock and record their position using satellite signals. Over time, the numbers show how the ground slowly moves. They can notice changes of just a few mil https://socialmedia.xdme.com/tony/videos-book12/page-050.mp4 https://www.youtube.com/embed/4hGkDnW4bLU 112 2026-10-03T10:12:24+00:00 yes https://xdme.com/watch-book12-q051.html https://xdme.com/book12-thumbs/page-051.jpg How Many Big Plates Does Earth Have, and Where Are They? Earth's outer shell is broken into huge pieces called plates, a bit like a cracked eggshell! There are seven big plates, plus several smaller ones. They fit together like a giant j https://socialmedia.xdme.com/tony/videos-book12/page-051.mp4 https://www.youtube.com/embed/5dztLt0m6uA 121 2026-10-03T10:15:28+00:00 yes https://xdme.com/watch-book12-q052.html https://xdme.com/book12-thumbs/page-052.jpg Why Is There a Mid-Atlantic Ridge? Deep under the Atlantic Ocean, two plates are slowly pulling apart! Hot rock rises into the gap, cools, and turns into brand new seafloor. That long, bumpy seam is called the Mid-A https://socialmedia.xdme.com/tony/videos-book12/page-052.mp4 https://www.youtube.com/embed/uHqC1eJS1ag 118 2026-10-03T10:18:12+00:00 yes https://xdme.com/watch-book12-q053.html https://xdme.com/book12-thumbs/page-053.jpg How Did the Rocky Mountains Form? The Rocky Mountains began as seafloor that was squeezed and lifted up into the sky! They started rising about 80 million years ago. Today they stretch from Canada all the way down https://socialmedia.xdme.com/tony/videos-book12/page-053.mp4 https://www.youtube.com/embed/y1uQjJrcq4s 118 2026-10-03T10:21:16+00:00 yes https://xdme.com/watch-book12-q054.html https://xdme.com/book12-thumbs/page-054.jpg How Fast Do Tectonic Plates Move? Tectonic plates move about as fast as your fingernails grow! That is around 2 to 10 centimeters a year. It is slow, but slow and steady can move whole continents. https://socialmedia.xdme.com/tony/videos-book12/page-054.mp4 https://www.youtube.com/embed/PaT66jeV6Fc 120 2026-10-03T10:23:48+00:00 yes https://xdme.com/watch-book12-q055.html https://xdme.com/book12-thumbs/page-055.jpg Why Is Iceland So Volcanic? Iceland is a land of volcanoes and hot springs! It sits where two plates are pulling apart and also on top of a hotspot, and both make lots of melted rock. That is why Iceland is s https://socialmedia.xdme.com/tony/videos-book12/page-055.mp4 https://www.youtube.com/embed/ZX78RmXG_zA 116 2026-10-03T10:26:51+00:00 yes https://xdme.com/watch-book12-q056.html https://xdme.com/book12-thumbs/page-056.jpg Why Do Hotspots Make Island Chains? Hotspots make chains of islands, like Hawaii! A hotspot is a place where hot rock rises from deep inside Earth. It melts through a plate, and a volcano grows on top of the hotspot. https://socialmedia.xdme.com/tony/videos-book12/page-056.mp4 https://www.youtube.com/embed/sT29a_Lx274 116 2026-10-03T10:29:25+00:00 yes https://xdme.com/watch-book12-q057.html https://xdme.com/book12-thumbs/page-057.jpg Why Is the Mariana Trench So Deep? The Mariana Trench is the deepest place in the whole ocean! It is nearly 11 kilometers straight down. That is deeper than Mount Everest is tall. https://socialmedia.xdme.com/tony/videos-book12/page-057.mp4 https://www.youtube.com/embed/JlkSdKgfFUs 116 2026-10-03T10:31:57+00:00 yes https://xdme.com/watch-book12-q058.html https://xdme.com/book12-thumbs/page-058.jpg Why Can You Find Seashells on Top of Mountains? Seashells on top of mountains are real, and here is why! The land there used to be under the sea. Moving plates lifted the old seafloor high into the sky, even to the top of Mount https://socialmedia.xdme.com/tony/videos-book12/page-058.mp4 https://www.youtube.com/embed/w0PPMEr_H8k 114 2026-10-03T10:35:00+00:00 yes https://xdme.com/watch-book12-q059.html https://xdme.com/book12-thumbs/page-059.jpg Why Do Matching Rock Belts Appear Across Oceans? Rocks on opposite sides of the Atlantic Ocean match each other! Rocks in Newfoundland and in Scotland are the same age and type. That is because they were once part of the same mou https://socialmedia.xdme.com/tony/videos-book12/page-059.mp4 https://www.youtube.com/embed/uEXmiUwukL4 117 2026-10-03T10:37:36+00:00 yes https://xdme.com/watch-book12-q060.html https://xdme.com/book12-thumbs/page-060.jpg Why Is Seafloor Younger Near Ridges? The seafloor is youngest right next to the ridge! New seafloor forms there and slowly moves away on both sides. So the farther you go, the older the rock gets. https://socialmedia.xdme.com/tony/videos-book12/page-060.mp4 https://www.youtube.com/embed/2cKFCsx4lg4 111 2026-10-03T10:40:39+00:00 yes https://xdme.com/watch-book12-q061.html https://xdme.com/book12-thumbs/page-061.jpg Why Are Some Rocks in Canada Billions of Years Old? Some rocks in Canada are about 4 billion years old! They are part of the Canadian Shield, some of the oldest land on Earth. Some of those very old rocks are in the Northwest Territ https://socialmedia.xdme.com/tony/videos-book12/page-061.mp4 https://www.youtube.com/embed/spbhq9o3LDg 116 2026-10-03T10:43:13+00:00 yes https://xdme.com/watch-book12-q062.html https://xdme.com/book12-thumbs/page-062.jpg Why Does Mantle Rock Move If It’s Solid? Deep inside Earth, solid rock can flow! The mantle is so hot and under so much pressure that it moves very slowly. It is a bit like warm putty that you can stretch if you pull it s https://socialmedia.xdme.com/tony/videos-book12/page-062.mp4 https://www.youtube.com/embed/DtF-FLM2Dn8 112 2026-10-03T10:46:16+00:00 yes https://xdme.com/watch-book12-q063.html https://xdme.com/book12-thumbs/page-063.jpg Why Do Rift Valleys Form? A rift valley forms where the ground is being pulled apart! The middle block drops down between two cracks, while the sides stay high. The result is a long valley with steep walls. https://socialmedia.xdme.com/tony/videos-book12/page-063.mp4 https://www.youtube.com/embed/O4sPhrXSYco 114 2026-10-03T10:48:50+00:00 yes https://xdme.com/watch-book12-q064.html https://xdme.com/book12-thumbs/page-064.jpg Why Are There Volcanoes Near Trenches? Volcanoes pop up near ocean trenches because of water! When one plate sinks under another, it carries water down with it. That water helps hot rock melt. https://socialmedia.xdme.com/tony/videos-book12/page-064.mp4 https://www.youtube.com/embed/DwK5MB0p-J4 115 2026-10-03T10:51:52+00:00 yes https://xdme.com/watch-book12-q065.html https://xdme.com/book12-thumbs/page-065.jpg Why Do Continents Have Deep Roots? Continents have deep roots, just like an iceberg floating in the sea! Thick, light crust floats on the heavier rock of the mantle. Most of it is hidden underneath, just like most o https://socialmedia.xdme.com/tony/videos-book12/page-065.mp4 https://www.youtube.com/embed/vYx64iWhjBE 116 2026-10-03T10:54:57+00:00 yes https://xdme.com/watch-book12-q066.html https://xdme.com/book12-thumbs/page-066.jpg Is Earth Shrinking as It Cools? Long ago, some scientists thought Earth was shrinking as it cooled and that mountains were wrinkles, like on a dried-up apple. Today we know that moving plates build mountains, and https://socialmedia.xdme.com/tony/videos-book12/page-066.mp4 https://www.youtube.com/embed/ZDZWXZBO4e8 119 2026-10-03T10:58:13+00:00 yes https://xdme.com/watch-book12-q067.html https://xdme.com/book12-thumbs/page-067.jpg Why Do Magnetic Stripes Decorate Seafloors? Seafloors have magnetic stripes, like a zebra! Earth's magnetic field flips from time to time. New seafloor records each flip as it forms, like a tape recorder. https://socialmedia.xdme.com/tony/videos-book12/page-067.mp4 https://www.youtube.com/embed/bjtedlJHwH0 115 2026-10-03T11:01:15+00:00 yes https://xdme.com/watch-book12-q068.html https://xdme.com/book12-thumbs/page-068.jpg Why Do Plate Maps Look Like Jigsaw Puzzles? Plate maps look like jigsaw puzzles because the plates really do fit together! The edges follow lines of earthquakes, volcanoes, and ridges. When people marked those on a map, big https://socialmedia.xdme.com/tony/videos-book12/page-068.mp4 https://www.youtube.com/embed/xdG2rpFZ4xo 114 2026-10-03T11:04:18+00:00 yes https://xdme.com/watch-book12-q069.html https://xdme.com/book12-thumbs/page-069.jpg How Do Scientists Know What Is Inside Earth When Nobody Has Ever Dug That Deep? Nobody has ever dug anywhere near the center of Earth, and the deepest hole ever drilled is only about 12 kilometers deep. Scientists learn what is inside by studying earthquake wa https://socialmedia.xdme.com/tony/videos-book12/page-069.mp4 https://www.youtube.com/embed/v30MucNGDBM 116 2026-10-03T11:08:03+00:00 yes https://xdme.com/watch-book12-q070.html https://xdme.com/book12-thumbs/page-070.jpg What Is a Microplate? A microplate is a small plate squeezed between big ones! Off the coast of British Columbia, there are two of them, side by side. They are the Juan de Fuca plate and the Explorer pl https://socialmedia.xdme.com/tony/videos-book12/page-070.mp4 https://www.youtube.com/embed/UAivVQ0rtuQ 115 2026-10-03T11:10:36+00:00 yes https://xdme.com/watch-book12-q071.html https://xdme.com/book12-thumbs/page-071.jpg What Does the Word “Tectonic” Mean? The word tectonic comes from an old Greek word, tekton, which means builder! Tectonic forces build and shape the surface of Earth. They are Earth's slow, powerful builders, working https://socialmedia.xdme.com/tony/videos-book12/page-071.mp4 https://www.youtube.com/embed/X_e5NSXjkjM 121 2026-10-03T11:13:55+00:00 yes https://xdme.com/watch-book12-q072.html https://xdme.com/book12-thumbs/page-072.jpg Why Do Some Earthquakes Happen Far Away From Plate Edges? Most earthquakes happen along plate edges, but a few happen far inside the plates! They happen along old cracks and weak spots in the rock. These surprise quakes are rarer, but the https://socialmedia.xdme.com/tony/videos-book12/page-072.mp4 https://www.youtube.com/embed/OoYtIzOf2CA 112 2026-10-03T11:16:58+00:00 yes https://xdme.com/watch-book12-q073.html https://xdme.com/book12-thumbs/page-073.jpg Why Does the Seafloor Get Recycled But the Continents Don’t? The seafloor gets recycled, but the continents mostly stay! Heavy seafloor sinks back into the mantle. Lighter continents float too high to sink, like a cork in a bowl of water. https://socialmedia.xdme.com/tony/videos-book12/page-073.mp4 https://www.youtube.com/embed/KKEg6RpBCL4 114 2026-10-03T11:20:01+00:00 yes https://xdme.com/watch-book12-q074.html https://xdme.com/book12-thumbs/page-074.jpg Why Will Maps Look Different in 50 Million Years? Maps will look different in 50 million years, because plates keep moving! We cannot see it, because the change is so slow. But scientists can predict the pattern, using GPS and wha https://socialmedia.xdme.com/tony/videos-book12/page-074.mp4 https://www.youtube.com/embed/AAfxg9XCrfE 119 2026-10-03T11:23:03+00:00 yes https://xdme.com/watch-book12-q075.html https://xdme.com/book12-thumbs/page-075.jpg Why Do Plates Help Explain So Many Things About Earth? Plates explain so many things about Earth! Volcanoes, earthquakes, mountains, and ocean trenches all happen because plates move. One big idea explains a whole planet's puzzle, from https://socialmedia.xdme.com/tony/videos-book12/page-075.mp4 https://www.youtube.com/embed/1dGfjiCz8rc 126 2026-10-03T11:28:15+00:00 yes https://xdme.com/watch-book12-q076.html https://xdme.com/book12-thumbs/page-076.jpg Why Do Hot Springs Bubble Up in Banff and Yukon? Hot springs bubble up in Banff and the Yukon, even though there are no active volcanoes nearby! Rain and melted snow soak deep into the ground, where the rock is warmer. The heated https://socialmedia.xdme.com/tony/videos-book12/page-076.mp4 https://www.youtube.com/embed/w6IYJU3lrdU 111 2026-10-03T08:07:40+00:00 yes https://xdme.com/watch-book12-q077.html https://xdme.com/book12-thumbs/page-077.jpg What Lives in Hot Springs That Would Be Too Hot for Most Animals? Tiny heat-loving microbes live in hot springs! They are called thermophiles, and they love water that would hurt most animals. They are true heat champions of nature. https://socialmedia.xdme.com/tony/videos-book12/page-077.mp4 https://www.youtube.com/embed/9AOPLRBh_Hk 116 2026-10-03T08:07:41+00:00 yes https://xdme.com/watch-book12-q078.html https://xdme.com/book12-thumbs/page-078.jpg Why Does a Coffee Percolator Work Like a Tiny Geyser? A coffee percolator works like a tiny geyser! Both use heat, a narrow tube, and trapped pressure. Old Faithful, a famous geyser in Yellowstone, erupts about every 90 minutes, on av https://socialmedia.xdme.com/tony/videos-book12/page-078.mp4 https://www.youtube.com/embed/Y2ZS6caI7yw 115 2026-10-03T08:07:50+00:00 yes https://xdme.com/watch-book12-q079.html https://xdme.com/book12-thumbs/page-079.jpg Why Do Hot Springs Have Bright Colors? Hot springs have bright colors because of tiny living things! Different microbes grow in different temperatures. Each one has its own color, like a box of crayons. https://socialmedia.xdme.com/tony/videos-book12/page-079.mp4 https://www.youtube.com/embed/chKkZNdBJbM 111 2026-10-03T08:07:52+00:00 yes https://xdme.com/watch-book12-q080.html https://xdme.com/book12-thumbs/page-080.jpg Why Can You Cook Food in Some Hot Springs (Historically)? Long ago, people sometimes cooked food in a few hot springs, because some are almost as hot as boiling water. Those springs can scald skin badly, so today nobody should touch the w https://socialmedia.xdme.com/tony/videos-book12/page-080.mp4 https://www.youtube.com/embed/ngXQDy_9ye4 114 2026-10-03T08:07:53+00:00 yes https://xdme.com/watch-book12-q081.html https://xdme.com/book12-thumbs/page-081.jpg Why Do Mud Pots Plop? A mud pot is a pool of thick, bubbling mud, and its bubbles pop with a plop! Steam and gases rise up through the ground and push through the sticky mud. Mud pots are scalding hot, https://socialmedia.xdme.com/tony/videos-book12/page-081.mp4 https://www.youtube.com/embed/SJ5hpeIu4nw 107 2026-10-03T08:07:55+00:00 yes https://xdme.com/watch-book12-q082.html https://xdme.com/book12-thumbs/page-082.jpg Why Do Fumaroles Hiss? A fumarole is a vent in the ground that lets out steam and gases, and it hisses like a kettle or a bike tire! Fumaroles can keep working for years after an eruption has ended. The https://socialmedia.xdme.com/tony/videos-book12/page-082.mp4 https://www.youtube.com/embed/yknddC_2NH8 109 2026-10-03T08:07:56+00:00 yes https://xdme.com/watch-book12-q083.html https://xdme.com/book12-thumbs/page-083.jpg Why Is Geothermal Energy Useful? Geothermal energy is heat from inside Earth, and it is very useful! It can make electricity and warm buildings. It works day and night, all year long, rain or shine. https://socialmedia.xdme.com/tony/videos-book12/page-083.mp4 https://www.youtube.com/embed/UIKoS3VirVc 120 2026-10-03T08:07:57+00:00 yes https://xdme.com/watch-book12-q084.html https://xdme.com/book12-thumbs/page-084.jpg Why Is the Water in Some Springs Warm But Not Boiling? Many springs are warm, but not boiling, which is perfect for soaking when it is safe! The water cools on its way up, or mixes with cooler groundwater. A spring's temperature is a c https://socialmedia.xdme.com/tony/videos-book12/page-084.mp4 https://www.youtube.com/embed/AEv4sI1ZKIM 115 2026-10-03T08:09:00+00:00 yes https://xdme.com/watch-book12-q085.html https://xdme.com/book12-thumbs/page-085.jpg Why Do Black Smokers Exist on the Seafloor? Black smokers are tall chimneys on the deep seafloor that puff out clouds of black water! Cold seawater seeps into cracks, gets heated by hot rock to over 350 degrees Celsius, and https://socialmedia.xdme.com/tony/videos-book12/page-085.mp4 https://www.youtube.com/embed/zceWOlgzmng 116 2026-10-03T08:12:03+00:00 yes https://xdme.com/watch-book12-q086.html https://xdme.com/book12-thumbs/page-086.jpg Why Do Strange Animals Live By Vents Without Sunlight? Strange animals live at deep ocean vents, where sunlight can never reach! Tiny microbes there make food from chemicals in the hot water instead of from sunshine. Tube worms, giant https://socialmedia.xdme.com/tony/videos-book12/page-086.mp4 https://www.youtube.com/embed/RPczT2E69rQ 114 2026-10-03T08:14:38+00:00 yes https://xdme.com/watch-book12-q087.html https://xdme.com/book12-thumbs/page-087.jpg Why Is Yellowstone Called a Supervolcano System? Yellowstone is called a supervolcano system because it sits on a giant bowl-shaped caldera! A caldera is a huge hole made when the ground collapses after a giant eruption. Yellowst https://socialmedia.xdme.com/tony/videos-book12/page-087.mp4 https://www.youtube.com/embed/VVKm8fdOroY 123 2026-10-03T08:17:41+00:00 yes https://xdme.com/watch-book12-q088.html https://xdme.com/book12-thumbs/page-088.jpg Why Do Travertine Terraces Form? Travertine terraces look like white stone staircases made by hot springs! They form where hot water with dissolved limestone flows out. The Banff hot springs make travertine, and s https://socialmedia.xdme.com/tony/videos-book12/page-088.mp4 https://www.youtube.com/embed/BnFF6_nTYSo 120 2026-10-03T08:20:18+00:00 yes https://xdme.com/watch-book12-q089.html https://xdme.com/book12-thumbs/page-089.jpg Why Are Some Springs Blue Like Paint? Some springs look as blue as paint! Clear, deep water takes away red light and sends blue light back to your eyes. That is why deep pools often look blue, like a piece of the sky. https://socialmedia.xdme.com/tony/videos-book12/page-089.mp4 https://www.youtube.com/embed/DtUNaKYdOm8 109 2026-10-03T08:22:56+00:00 yes https://xdme.com/watch-book12-q090.html https://xdme.com/book12-thumbs/page-090.jpg Why Must You Stay on Boardwalks in Geothermal Parks? In geothermal parks, you must always stay on the boardwalk! The ground around hot springs can look solid, but it may not be. The rule is simple and it keeps everyone safe. https://socialmedia.xdme.com/tony/videos-book12/page-090.mp4 https://www.youtube.com/embed/GsK2foyEe6A 111 2026-10-03T08:25:29+00:00 yes https://xdme.com/watch-book12-q091.html https://xdme.com/book12-thumbs/page-091.jpg Why Do Minerals Color Rocks Red or Yellow Near Vents? Rocks near hot vents can turn red or yellow! Heat and water change the minerals in the rock. Geologists use those colors as clues. https://socialmedia.xdme.com/tony/videos-book12/page-091.mp4 https://www.youtube.com/embed/cMw2_NaSc88 111 2026-10-03T08:28:32+00:00 yes https://xdme.com/watch-book12-q092.html https://xdme.com/book12-thumbs/page-092.jpg Why Do Volcanoes Create Fertile Soil Later? Volcanoes can create super fertile soil, but only later, after many years! When lava and ash slowly break down, they turn into rich dirt. Plants love it, and so do farmers. https://socialmedia.xdme.com/tony/videos-book12/page-092.mp4 https://www.youtube.com/embed/vm_vkcQWWo0 123 2026-10-03T08:34:35+00:00 yes https://xdme.com/watch-book12-q093.html https://xdme.com/book12-thumbs/page-093.jpg Why Do People Bathe in Safe Hot Springs? People bathe in safe hot springs because warm water feels wonderful! It relaxes tired muscles and feels soothing. But only specially managed pools are safe for swimming, and kids n https://socialmedia.xdme.com/tony/videos-book12/page-093.mp4 https://www.youtube.com/embed/_F9cHv6CGTg 115 2026-10-03T08:37:08+00:00 yes https://xdme.com/watch-book12-q094.html https://xdme.com/book12-thumbs/page-094.jpg Why Does Steam From Hot Springs Look Bigger on Cold or Damp Days? The white cloud above a hot spring is not really steam, because real steam is invisible! It is made of tiny droplets of liquid water floating in the air. It looks biggest on cold o https://socialmedia.xdme.com/tony/videos-book12/page-094.mp4 https://www.youtube.com/embed/kjNyv1lFyVU 111 2026-10-03T08:39:41+00:00 yes https://xdme.com/watch-book12-q095.html https://xdme.com/book12-thumbs/page-095.jpg Why Do Sinter Terraces Look Different From Travertine? Sinter and travertine are both crusts left behind by hot springs, but they are made of different minerals. Sinter is glassy, while travertine is chalky. Same idea, different ingred https://socialmedia.xdme.com/tony/videos-book12/page-095.mp4 https://www.youtube.com/embed/B5YXtBDj2eM 120 2026-10-03T08:42:43+00:00 yes https://xdme.com/watch-book12-q096.html https://xdme.com/book12-thumbs/page-096.jpg Why Do Scientists Sample Spring Water Chemistry? Scientists sample hot spring water because water carries clues! The water is a mix of chemicals that tell a story about what is happening underground. It is like reading a secret m https://socialmedia.xdme.com/tony/videos-book12/page-096.mp4 https://www.youtube.com/embed/27LJ4_Q2LGc 118 2026-10-03T08:45:46+00:00 yes https://xdme.com/watch-book12-q097.html https://xdme.com/book12-thumbs/page-097.jpg Why Does the Ground Stay the Same Temperature All Year a Few Meters Down? A few meters down, the ground stays about the same temperature all year! It is warmer than winter air and cooler than summer air. It is a steady layer of Earth's blanket. https://socialmedia.xdme.com/tony/videos-book12/page-097.mp4 https://www.youtube.com/embed/Qq5wYMX-cdQ 114 2026-10-03T08:48:20+00:00 yes https://xdme.com/watch-book12-q098.html https://xdme.com/book12-thumbs/page-098.jpg Why Do Lava Fields Look Lifeless Then Bloom Later? New lava rock looks empty, but life starts quickly! Tough pioneers like mosses and lichens move in first and help make soil for later plants. A black lava field can turn green in j https://socialmedia.xdme.com/tony/videos-book12/page-098.mp4 https://www.youtube.com/embed/ZVpF65rj_8U 116 2026-10-03T08:51:29+00:00 yes https://xdme.com/watch-book12-q099.html https://xdme.com/book12-thumbs/page-099.jpg How Do Diamonds Come Up From Deep Inside Earth? Diamonds form deep underground, over 150 kilometers down, where heat and pressure squeeze carbon into crystals. A special, speedy magma called kimberlite blasts upward and carries https://socialmedia.xdme.com/tony/videos-book12/page-099.mp4 https://www.youtube.com/embed/YDK6zyxLuZ4 125 2026-10-03T08:57:02+00:00 yes https://xdme.com/watch-book12-q100.html https://xdme.com/book12-thumbs/page-100.jpg How Do Volcanic Landscapes Keep Changing? Volcanic landscapes are always changing! New rock arrives, old rock wears away, and life moves in. That makes volcano country feel alive, because it never stops changing. https://socialmedia.xdme.com/tony/videos-book12/page-100.mp4 https://www.youtube.com/embed/cLq2Eopa-yw 116 2026-10-03T08:59:35+00:00 yes https://xdme.com/watch-book12-q101.html https://xdme.com/book12-thumbs/page-101.jpg Why Do Tiltmeters Watch Volcanoes? Tiltmeters watch volcanoes because rising magma can make the ground swell and tilt a tiny bit. A tiltmeter is a super sensitive level. If the tilt keeps growing, scientists look cl https://socialmedia.xdme.com/tony/videos-book12/page-101.mp4 https://www.youtube.com/embed/H-zzs8Xo4Uc 115 2026-10-03T09:02:37+00:00 yes https://xdme.com/watch-book12-q102.html https://xdme.com/book12-thumbs/page-102.jpg Why Do Scientists Measure Volcano Gases? Scientists measure volcano gases because magma gives off gas as it rises and the pressure drops. More gas can mean fresh magma is closer to the surface. The mix of gases is a clue, https://socialmedia.xdme.com/tony/videos-book12/page-102.mp4 https://www.youtube.com/embed/UctijdErB18 119 2026-10-03T09:05:10+00:00 yes https://xdme.com/watch-book12-q103.html https://xdme.com/book12-thumbs/page-103.jpg Why Do Seismometers Listen for Magma Earthquakes? Seismometers listen for magma earthquakes because moving magma and hot fluids shake the rock around them. Each kind of shaking has its own signature. A change in the pattern can me https://socialmedia.xdme.com/tony/videos-book12/page-103.mp4 https://www.youtube.com/embed/KTvs2vNtShQ 114 2026-10-03T09:08:13+00:00 yes https://xdme.com/watch-book12-q104.html https://xdme.com/book12-thumbs/page-104.jpg Why Do Scientists Use Heat Cameras on Volcanoes? Scientists use heat cameras on volcanoes because a thermal camera sees heat, not light. It can show hot spots, warm cracks, and glowing lava, even through smoke or in the dark. A w https://socialmedia.xdme.com/tony/videos-book12/page-104.mp4 https://www.youtube.com/embed/Wm8GWH47aRY 116 2026-10-03T09:10:46+00:00 yes https://xdme.com/watch-book12-q105.html https://xdme.com/book12-thumbs/page-105.jpg Why Do Drones Help Volcanologists? Drones help volcanologists because they can fly places that are too dangerous for people. Scientists steer them from a safe distance. That means more information and less risk. https://socialmedia.xdme.com/tony/videos-book12/page-105.mp4 https://www.youtube.com/embed/bPlQmLrDfb8 112 2026-10-03T09:13:24+00:00 yes https://xdme.com/watch-book12-q106.html https://xdme.com/book12-thumbs/page-106.jpg Why Do Ash Samples Get Studied Under Microscopes? Scientists study ash under microscopes because volcanic ash is made of tiny pieces of broken glass and crystal. The shapes and kinds of pieces tell the story of the eruption. A pin https://socialmedia.xdme.com/tony/videos-book12/page-106.mp4 https://www.youtube.com/embed/ds0LgWowUag 113 2026-10-03T09:16:39+00:00 yes https://xdme.com/watch-book12-q107.html https://xdme.com/book12-thumbs/page-107.jpg Why Are Hazard Maps Colorful? Hazard maps are colorful because colors show, at a glance, what could happen where. Each color is a zone, and each zone has its own level of danger. People use the maps to plan roa https://socialmedia.xdme.com/tony/videos-book12/page-107.mp4 https://www.youtube.com/embed/aRw7w-gTJ8E 118 2026-10-03T09:19:11+00:00 yes https://xdme.com/watch-book12-q108.html https://xdme.com/book12-thumbs/page-108.jpg Why Do Lahars Scare Scientists? Lahars scare scientists because they are fast mudflows that can travel far down river valleys. A lahar is a mix of ash, rocks, and water that moves like a river of wet concrete. Pe https://socialmedia.xdme.com/tony/videos-book12/page-108.mp4 https://www.youtube.com/embed/MNBzHd2Nv7w 115 2026-10-03T09:21:43+00:00 yes https://xdme.com/watch-book12-q109.html https://xdme.com/book12-thumbs/page-109.jpg What Is a Volcano Observatory, and What Happens Inside It? A volcano observatory is a place where scientists watch volcano data day and night. It works a bit like a weather center, but for volcanoes. When something changes, they tell offic https://socialmedia.xdme.com/tony/videos-book12/page-109.mp4 https://www.youtube.com/embed/WIzRBII8G7M 119 2026-10-03T09:24:48+00:00 yes https://xdme.com/watch-book12-q110.html https://xdme.com/book12-thumbs/page-110.jpg Why Do Volcanologists Sometimes Say “Restless”? Volcanologists say restless when a volcano shows unusual signs, like more earthquakes, ground swelling, or more gas. Restless is a yellow light, not a red one. Most restless volcan https://socialmedia.xdme.com/tony/videos-book12/page-110.mp4 https://www.youtube.com/embed/6-RA-lX1Eho 119 2026-10-03T09:27:20+00:00 yes https://xdme.com/watch-book12-q111.html https://xdme.com/book12-thumbs/page-111.jpg Why Do Past Eruption Deposits Guide Future Forecasts? Past eruption deposits guide forecasts because volcanoes tend to repeat their habits. Layers of old lava and ash show where eruptions went and how big they were. The past is a guid https://socialmedia.xdme.com/tony/videos-book12/page-111.mp4 https://www.youtube.com/embed/Sp83Q2rZoJg 112 2026-10-03T09:30:23+00:00 yes https://xdme.com/watch-book12-q112.html https://xdme.com/book12-thumbs/page-112.jpg Why Is Volcano Tourism Guided Carefully? Volcano tourism is guided carefully because volcanic areas can be dangerous, even on quiet days. Trained guides know the paths and check conditions. Following the rules lets visito https://socialmedia.xdme.com/tony/videos-book12/page-112.mp4 https://www.youtube.com/embed/W9tXjqnWBHQ 121 2026-10-03T09:32:54+00:00 yes https://xdme.com/watch-book12-q113.html https://xdme.com/book12-thumbs/page-113.jpg Why Do Webcams Sit on Crater Rims? Webcams sit on crater rims because a camera never blinks. They send pictures every few minutes, day and night. Scientists can see small changes and look back at earlier images. https://socialmedia.xdme.com/tony/videos-book12/page-113.mp4 https://www.youtube.com/embed/77a2CVHxmh4 112 2026-10-03T09:35:58+00:00 yes https://xdme.com/watch-book12-q114.html https://xdme.com/book12-thumbs/page-114.jpg How Can Microphones Hear Volcanoes From Far Away? Microphones can hear volcanoes from far away because big explosions make infrasound. Infrasound is sound so low-pitched that people cannot hear it. These waves can travel thousands https://socialmedia.xdme.com/tony/videos-book12/page-114.mp4 https://www.youtube.com/embed/oj2B2t1CJGE 116 2026-10-03T09:38:30+00:00 yes https://xdme.com/watch-book12-q115.html https://xdme.com/book12-thumbs/page-115.jpg Why Do Rockfalls Not Always Mean Magma? Rockfalls do not always mean magma because rocks tumble on steep slopes for many reasons. Rain, melting snow, and freezing and thawing can all loosen rocks. Careful detectives rule https://socialmedia.xdme.com/tony/videos-book12/page-115.mp4 https://www.youtube.com/embed/7dde4xdTDGg 121 2026-10-03T09:41:35+00:00 yes https://xdme.com/watch-book12-q116.html https://xdme.com/book12-thumbs/page-116.jpg Why Do Some Volcanoes Erupt Again and Again for Years? Some volcanoes erupt again and again because magma keeps rising from below. As long as the supply keeps coming and the path to the surface stays open, eruptions can continue. A ste https://socialmedia.xdme.com/tony/videos-book12/page-116.mp4 https://www.youtube.com/embed/ZWpVO_u97HQ 123 2026-10-03T09:44:07+00:00 yes https://xdme.com/watch-book12-q117.html https://xdme.com/book12-thumbs/page-117.jpg Why Do Airplanes Avoid Ash Clouds? Airplanes avoid ash clouds because volcanic ash is made of tiny pieces of rock and glass. Inside a hot jet engine, that ash can melt and stick. That can make the engine stop, so pi https://socialmedia.xdme.com/tony/videos-book12/page-117.mp4 https://www.youtube.com/embed/0NYBA140Qms 116 2026-10-03T09:47:09+00:00 yes https://xdme.com/watch-book12-q118.html https://xdme.com/book12-thumbs/page-118.jpg Why Do Volcanoes Exist on Other Planets and Moons? Volcanoes are not only on Earth! Mars has a giant volcano called Olympus Mons, Jupiter's moon Io has hundreds of active volcanoes, and Saturn's moon Enceladus has icy volcanoes tha https://socialmedia.xdme.com/tony/videos-book12/page-118.mp4 https://www.youtube.com/embed/pXs-hZmuSlk 127 2026-10-03T09:49:42+00:00 yes https://xdme.com/watch-book12-q119.html https://xdme.com/book12-thumbs/page-119.jpg Why Do Tree Rings Near Volcanoes Tell Stories? Tree rings near volcanoes tell stories because trees grow a new ring every year. Each ring is a page in the tree's diary, and eruptions can leave marks on those pages. Scientists r https://socialmedia.xdme.com/tony/videos-book12/page-119.mp4 https://www.youtube.com/embed/1WKCbS6DztM 114 2026-10-03T09:55:05+00:00 yes https://xdme.com/watch-book12-q120.html https://xdme.com/book12-thumbs/page-120.jpg How Can Ordinary People Help Scientists Measure Ash? Ordinary people can help scientists measure ash, because one scientist cannot be everywhere. When ash falls, grown-ups can report how thick it is and where it landed, but only afte https://socialmedia.xdme.com/tony/videos-book12/page-120.mp4 https://www.youtube.com/embed/_a0-sMrglx8 110 2026-10-03T09:58:10+00:00 yes https://xdme.com/watch-book12-q121.html https://xdme.com/book12-thumbs/page-121.jpg Why Do Labs Recreate Magma in Furnaces? Labs recreate magma in furnaces because scientists cannot visit the inside of a real volcano. They melt rocks and test how the melt behaves. It is like running an eruption again an https://socialmedia.xdme.com/tony/videos-book12/page-121.mp4 https://www.youtube.com/embed/WVqufowJwqA 120 2026-10-03T10:01:13+00:00 yes https://xdme.com/watch-book12-q122.html https://xdme.com/book12-thumbs/page-122.jpg How Do Scientists Study a Volcano’s Crater Lake or Glacier? Many volcanoes have lakes in their craters or glaciers on their slopes, and both can be hazards. Scientists study them to learn about heat and water. A volcano's lake can act like https://socialmedia.xdme.com/tony/videos-book12/page-122.mp4 https://www.youtube.com/embed/80s7B_dJTb0 115 2026-10-03T10:04:16+00:00 yes https://xdme.com/watch-book12-q123.html https://xdme.com/book12-thumbs/page-123.jpg Why Do Volcano Scientists Admit What They Don’t Know? Volcano scientists admit what they do not know because every volcano is a little different. Many are hidden deep inside rock, so no one can know everything. Honesty makes science s https://socialmedia.xdme.com/tony/videos-book12/page-123.mp4 https://www.youtube.com/embed/mPzsuLJclNs 118 2026-10-03T10:07:19+00:00 yes https://xdme.com/watch-book12-q124.html https://xdme.com/book12-thumbs/page-124.jpg Why Do Museums Keep Eruption Artifacts? Museums keep eruption artifacts because old objects and records help us learn from the past. Ash samples, rocks, tools, photographs, and written records all tell part of the story. https://socialmedia.xdme.com/tony/videos-book12/page-124.mp4 https://www.youtube.com/embed/c0NMEnJt1MY 115 2026-10-03T10:09:52+00:00 yes https://xdme.com/watch-book12-q125.html https://xdme.com/book12-thumbs/page-125.jpg What Jobs Study Volcanoes? Many different jobs study volcanoes, because volcano research needs many kinds of people. Some work outdoors, some in labs, and some at computers or in classrooms. Curiosity, math, https://socialmedia.xdme.com/tony/videos-book12/page-125.mp4 https://www.youtube.com/embed/_rtp6IwJDz0 124 2026-10-03T10:12:27+00:00 yes https://xdme.com/watch-book12-q126.html https://xdme.com/book12-thumbs/page-126.jpg Why Do People Live Near Volcanoes Anyway? People live near volcanoes for many good reasons. Families have lived there for generations, and their homes, work, and communities are there. With good monitoring and practice, pe https://socialmedia.xdme.com/tony/videos-book12/page-126.mp4 https://www.youtube.com/embed/K4V265cYpjQ 118 2026-10-03T10:15:38+00:00 yes https://xdme.com/watch-book12-q127.html https://xdme.com/book12-thumbs/page-127.jpg Why Are Some Beaches Green? Some beaches are green because their sand is made of tiny green crystals from volcanic rock. The crystals are a mineral called olivine. Waves leave the heavy green crystals on the https://socialmedia.xdme.com/tony/videos-book12/page-127.mp4 https://www.youtube.com/embed/PsNoQ8UXveI 115 2026-10-03T10:18:14+00:00 yes https://xdme.com/watch-book12-q128.html https://xdme.com/book12-thumbs/page-128.jpg Why Do Building Codes Matter in Lava Zones? Building codes matter in lava zones because good design can reduce harm, even though it cannot stop a volcano. Codes are rules about where and how to build. Engineers study past er https://socialmedia.xdme.com/tony/videos-book12/page-128.mp4 https://www.youtube.com/embed/OITeQbM-DW4 114 2026-10-03T10:20:45+00:00 yes https://xdme.com/watch-book12-q129.html https://xdme.com/book12-thumbs/page-129.jpg How Do Towns Near Volcanoes Keep Their Water Clean When Ash Falls? Towns near volcanoes protect their water because falling ash can get into rivers, lakes, and reservoirs. Ash can make the water cloudy and change its chemistry. Clean water is one https://socialmedia.xdme.com/tony/videos-book12/page-129.mp4 https://www.youtube.com/embed/Pwe5ZPqlGEs 112 2026-10-03T10:23:50+00:00 yes https://xdme.com/watch-book12-q130.html https://xdme.com/book12-thumbs/page-130.jpg Why Do Special Masks Help When Ash Is in the Air? Special masks help when ash is in the air because ash is made of tiny sharp bits of rock and glass. Those bits can irritate eyes, noses, and lungs. A good filter mask catches much https://socialmedia.xdme.com/tony/videos-book12/page-130.mp4 https://www.youtube.com/embed/sQEWLPSUZys 114 2026-10-03T10:26:52+00:00 yes https://xdme.com/watch-book12-q131.html https://xdme.com/book12-thumbs/page-131.jpg Why Is Heavy Wet Ash a Danger to Roofs? Heavy wet ash is a danger to roofs because ash gets much heavier when it is wet. Dry ash is light, but wet ash is like wet cement. A few centimeters can weigh a lot. https://socialmedia.xdme.com/tony/videos-book12/page-131.mp4 https://www.youtube.com/embed/TDWs_nqQ_9A 108 2026-10-03T10:29:26+00:00 yes https://xdme.com/watch-book12-q132.html https://xdme.com/book12-thumbs/page-132.jpg Why Do Farmers Watch Wind Forecasts Around Vents? Farmers watch wind forecasts around vents because wind carries ash and decides where it falls. Wind is the delivery truck for ash. A shift in wind direction can change where the da https://socialmedia.xdme.com/tony/videos-book12/page-132.mp4 https://www.youtube.com/embed/1t--r--NaS0 116 2026-10-03T10:32:29+00:00 yes https://xdme.com/watch-book12-q133.html https://xdme.com/book12-thumbs/page-133.jpg Why Do Towns Near Volcanoes Paint Evacuation Signs Along Their Roads? Towns near volcanoes paint evacuation signs along their roads to show the way to safer, higher ground. Signs are easy to follow, even when people are stressed or it is dark. Clear https://socialmedia.xdme.com/tony/videos-book12/page-133.mp4 https://www.youtube.com/embed/jgyKHpMsQzQ 114 2026-10-03T10:35:01+00:00 yes https://xdme.com/watch-book12-q134.html https://xdme.com/book12-thumbs/page-134.jpg How Do Scientists Find Out When a Volcano Last Erupted? Scientists find out when a volcano last erupted by using dating tools like radiocarbon dating, tree rings, and ash layers. Old eruptions leave a calendar in the ground. Putting the https://socialmedia.xdme.com/tony/videos-book12/page-134.mp4 https://www.youtube.com/embed/cx1mJtbt5ZI 113 2026-10-03T10:37:37+00:00 yes https://xdme.com/watch-book12-q135.html https://xdme.com/book12-thumbs/page-135.jpg Why Do Volcano Danger Zones Keep People Out? Danger zones keep people out because the area near an erupting or restless volcano can be very risky. Lava, hot gas, falling rocks, and ash are most dangerous close to the crater. https://socialmedia.xdme.com/tony/videos-book12/page-135.mp4 https://www.youtube.com/embed/3eG0oXP81tE 117 2026-10-03T10:40:40+00:00 yes https://xdme.com/watch-book12-q136.html https://xdme.com/book12-thumbs/page-136.jpg Why Do Ships Care About Underwater Volcanoes? Ships care about underwater volcanoes because they can erupt without any warning at the surface. They can make floating rafts of rock, shallow new islands, and sudden bursts of ste https://socialmedia.xdme.com/tony/videos-book12/page-136.mp4 https://www.youtube.com/embed/7b1pbGXTuGo 118 2026-10-03T10:43:14+00:00 yes https://xdme.com/watch-book12-q137.html https://xdme.com/book12-thumbs/page-137.jpg How Do Towns Near Volcanoes Warn People Quickly? Towns near volcanoes warn people quickly by using several kinds of alerts together. That way, people hear the message even if one method fails. Warning systems are practiced so the https://socialmedia.xdme.com/tony/videos-book12/page-137.mp4 https://www.youtube.com/embed/hZ2wCFy2jBA 114 2026-10-03T10:46:18+00:00 yes https://xdme.com/watch-book12-q138.html https://xdme.com/book12-thumbs/page-138.jpg Why Do Schools Teach Volcano Units in Risky Regions? Schools in risky regions teach volcano units because kids who know the plan keep families safer. Knowing the science also takes away some of the fear. Children can be helpers at ho https://socialmedia.xdme.com/tony/videos-book12/page-138.mp4 https://www.youtube.com/embed/gd12lFiN6Hs 117 2026-10-03T10:48:51+00:00 yes https://xdme.com/watch-book12-q139.html https://xdme.com/book12-thumbs/page-139.jpg Why Does Staying Calm Help in an Emergency? Staying calm helps in an emergency because a calm brain can think and listen better. Feeling scared or frozen is normal. Calm is a skill you can practice. https://socialmedia.xdme.com/tony/videos-book12/page-139.mp4 https://www.youtube.com/embed/iNT7xd6YIF4 108 2026-10-03T10:51:54+00:00 yes https://xdme.com/watch-book12-q140.html https://xdme.com/book12-thumbs/page-140.jpg Why Do Pets and Farm Animals Need a Plan During an Eruption? Pets and farm animals need a plan during an eruption because they cannot make plans on their own. Their families have to plan for them. Planning ahead helps everyone stay together. https://socialmedia.xdme.com/tony/videos-book12/page-140.mp4 https://www.youtube.com/embed/iWLf7tPiGA8 111 2026-10-03T10:55:11+00:00 yes https://xdme.com/watch-book12-q141.html https://xdme.com/book12-thumbs/page-141.jpg Why Do Artists and Scientists Both Love Volcanoes? Artists and scientists both love volcanoes because both are drawn by their power and beauty. Both need patience and careful observation. Artists show how a volcano feels, and scien https://socialmedia.xdme.com/tony/videos-book12/page-141.mp4 https://www.youtube.com/embed/KxkPR4oKP1Y 122 2026-10-03T10:58:14+00:00 yes https://xdme.com/watch-book12-q142.html https://xdme.com/book12-thumbs/page-142.jpg Why Do Sibling Volcanoes in a Chain Erupt Differently? Neighboring volcanoes in a chain can erupt very differently because each has its own magma and plumbing. Neighbors are not copies. Magma recipe and plumbing shape a volcano's perso https://socialmedia.xdme.com/tony/videos-book12/page-142.mp4 https://www.youtube.com/embed/WYUx7bbI7KM 120 2026-10-03T11:01:17+00:00 yes https://xdme.com/watch-book12-q143.html https://xdme.com/book12-thumbs/page-143.jpg What Can Volcanic Rock Be Used for in Everyday Life? Volcanic rock is useful in everyday life, and people have used it for thousands of years. Light, bubbly pumice smooths surfaces, crushed basalt makes strong gravel, and ash mixed i https://socialmedia.xdme.com/tony/videos-book12/page-143.mp4 https://www.youtube.com/embed/Mo5_lajhtfQ 119 2026-10-03T11:04:20+00:00 yes https://xdme.com/watch-book12-q144.html https://xdme.com/book12-thumbs/page-144.jpg Why Do Kids’ Questions Help Whole Towns? Kids' questions help whole towns because questions make adults think. A good question can start a good plan. Curious kids make communities stronger. https://socialmedia.xdme.com/tony/videos-book12/page-144.mp4 https://www.youtube.com/embed/s3wEALgziPY 113 2026-10-03T11:08:04+00:00 yes https://xdme.com/watch-book12-q145.html https://xdme.com/book12-thumbs/page-145.jpg Why Do Scientists Celebrate Quiet Years Too? Scientists celebrate quiet years because a quiet volcano is good news for towns and for science. Quiet times show what normal looks like. Without a baseline, a change is hard to no https://socialmedia.xdme.com/tony/videos-book12/page-145.mp4 https://www.youtube.com/embed/utcZnoY4nEI 114 2026-10-03T11:10:54+00:00 yes https://xdme.com/watch-book12-q146.html https://xdme.com/book12-thumbs/page-146.jpg Why Will New Islands Keep Appearing Sometimes? New islands keep appearing sometimes because undersea volcanoes can build up until they poke above the waves. It happens when a volcano erupts again and again. A brand new island s https://socialmedia.xdme.com/tony/videos-book12/page-146.mp4 https://www.youtube.com/embed/xuUh7RLhgE8 118 2026-10-03T11:13:56+00:00 yes https://xdme.com/watch-book12-q147.html https://xdme.com/book12-thumbs/page-147.jpg How Tall Can a Volcano Grow? A volcano can grow very tall, but there is a limit. Its height depends on how strong the rock is and how strong gravity is. A pile can only get so steep before it slumps. https://socialmedia.xdme.com/tony/videos-book12/page-147.mp4 https://www.youtube.com/embed/Mxac9WRXlUo 111 2026-10-03T11:17:00+00:00 yes https://xdme.com/watch-book12-q148.html https://xdme.com/book12-thumbs/page-148.jpg How Do Scientists Decide When to Warn People About a Volcano? Scientists decide when to warn people by working as a team. No one person sees the whole picture. Working together makes warnings more reliable. https://socialmedia.xdme.com/tony/videos-book12/page-148.mp4 https://www.youtube.com/embed/W-lM3TO0uaI 121 2026-10-03T11:20:02+00:00 yes https://xdme.com/watch-book12-q149.html https://xdme.com/book12-thumbs/page-149.jpg Why Can People Feel Hopeful Living Near Volcanoes? People can feel hopeful living near volcanoes because volcano country is safer today than 100 years ago. Better instruments, maps, and plans are the reason. Science plus planning w https://socialmedia.xdme.com/tony/videos-book12/page-149.mp4 https://www.youtube.com/embed/uuD4uWGtIrg 123 2026-10-03T11:23:05+00:00 yes https://xdme.com/watch-book12-q150.html https://xdme.com/book12-thumbs/page-150.jpg Why Is Earth the Only Planet We Know with Moving Plates? Earth is the only planet we know that has moving plates. Its crust is cracked into big pieces that slowly slide around. Earth has the right size, heat, and water to keep them movin https://socialmedia.xdme.com/tony/videos-book12/page-150.mp4 https://www.youtube.com/embed/QRHFXhN4kYk 112 2026-10-03T11:27:43+00:00 yes https://xdme.com/watch-book13-q001.html https://xdme.com/book13-thumbs/page-001.jpg Why Does Light Travel in Straight Lines? Light travels in straight lines unless something bends it, bounces it, or blocks it. That is why a flashlight beam looks like a stick of light. It is also why you cannot see around https://socialmedia.xdme.com/tony/videos-book13/page-001.mp4 https://www.youtube.com/embed/CS6yFlO7HeA 115 2026-10-03T12:10:23+00:00 yes https://xdme.com/watch-book13-q002.html https://xdme.com/book13-thumbs/page-002.jpg Why Is Light the Fastest Thing There Is? Light zooms along at about 300,000 kilometers every second! In one second, it could circle Earth more than 7 times. Nothing we know of travels faster. https://socialmedia.xdme.com/tony/videos-book13/page-002.mp4 https://www.youtube.com/embed/0Q9zSWUiGT8 112 2026-10-03T12:10:24+00:00 yes https://xdme.com/watch-book13-q003.html https://xdme.com/book13-thumbs/page-003.jpg Why Does Sunshine Take About Eight Minutes to Reach Earth? The Sun is about 150 million kilometers away from Earth. Even light needs about 8 minutes and 20 seconds to make that trip. So the sunshine on your face left the Sun a little over https://socialmedia.xdme.com/tony/videos-book13/page-003.mp4 https://www.youtube.com/embed/Zcr2FO9xZiY 117 2026-10-03T12:10:27+00:00 yes https://xdme.com/watch-book13-q004.html https://xdme.com/book13-thumbs/page-004.jpg Why Can You See a Sunbeam Streaming Through Dusty Air? Light itself is invisible as it flies through clean air. You see a sunbeam only when dust, smoke, or tiny water droplets bounce some light toward your eyes. The beam was there all https://socialmedia.xdme.com/tony/videos-book13/page-004.mp4 https://www.youtube.com/embed/7Bit2mY5m-c 117 2026-10-03T12:10:28+00:00 yes https://xdme.com/watch-book13-q005.html https://xdme.com/book13-thumbs/page-005.jpg Why Are the Spots of Sunlight Under a Tree Round? Tiny gaps between leaves work like pinholes. Each gap makes a little picture of the Sun on the ground. The Sun is round, so every picture is a round spot! https://socialmedia.xdme.com/tony/videos-book13/page-005.mp4 https://www.youtube.com/embed/hD5bTYsyENY 111 2026-10-03T12:10:30+00:00 yes https://xdme.com/watch-book13-q006.html https://xdme.com/book13-thumbs/page-006.jpg Why Can a Shadow Look Sharp One Minute and Fuzzy the Next? A shadow is sharpest when the light is a tiny source and the object is close to the surface. When the light is bigger, or the object is farther away, the edge turns soft and fuzzy. https://socialmedia.xdme.com/tony/videos-book13/page-006.mp4 https://www.youtube.com/embed/lxsC-glf_kM 111 2026-10-03T12:10:32+00:00 yes https://xdme.com/watch-book13-q007.html https://xdme.com/book13-thumbs/page-007.jpg Why Do You Get More than One Shadow Under Several Lamps? Every lamp is a separate source of light, and each one throws its own shadow behind your body. So several lamps make several shadows! The shadows point in different directions. https://socialmedia.xdme.com/tony/videos-book13/page-007.mp4 https://www.youtube.com/embed/90w8J6Fog38 113 2026-10-03T12:10:33+00:00 yes https://xdme.com/watch-book13-q008.html https://xdme.com/book13-thumbs/page-008.jpg Why Are Shadows on Snow Sometimes Blue? Shaded snow looks blue because it is lit by the blue sky instead of direct sunshine. The sky scatters blue light in every direction, and that light fills the shadow. Look for it ne https://socialmedia.xdme.com/tony/videos-book13/page-008.mp4 https://www.youtube.com/embed/COeP5Lt9qKI 116 2026-10-03T12:10:34+00:00 yes https://xdme.com/watch-book13-q009.html https://xdme.com/book13-thumbs/page-009.jpg Why Can a Flashlight and Your Hands Make a Shadow Animal? A shadow forms where something blocks light. Your hands are the object, and the wall catches the shape. Light travels straight, so the shadow keeps your hand's outline! https://socialmedia.xdme.com/tony/videos-book13/page-009.mp4 https://www.youtube.com/embed/5cTvEVfnAQo 115 2026-10-03T12:10:36+00:00 yes https://xdme.com/watch-book13-q010.html https://xdme.com/book13-thumbs/page-010.jpg Why Does a Glass of Water Throw a Bright, Wiggly Shadow? A clear glass of water is not invisible to light. Its curved sides bend the light, and the water focuses some of it into bright lines and patches. That makes a shadow with a glowin https://socialmedia.xdme.com/tony/videos-book13/page-010.mp4 https://www.youtube.com/embed/jXUc9MnYISA 120 2026-10-03T12:10:38+00:00 yes https://xdme.com/watch-book13-q011.html https://xdme.com/book13-thumbs/page-011.jpg Why Is It Cooler in the Shade than in the Sun? Shade blocks the direct beams of the Sun. The heat energy in sunlight cannot warm you or the ground there. That is why shade feels cooler than the sunny spot beside it. https://socialmedia.xdme.com/tony/videos-book13/page-011.mp4 https://www.youtube.com/embed/s3h356ls7h8 116 2026-10-03T12:10:39+00:00 yes https://xdme.com/watch-book13-q012.html https://xdme.com/book13-thumbs/page-012.jpg Why Do Dark Clothes Feel Hotter in the Sun than Light Ones? Dark colors soak up most of the light that hits them. They turn that light energy into heat. Light colors bounce more light away, so they stay cooler. https://socialmedia.xdme.com/tony/videos-book13/page-012.mp4 https://www.youtube.com/embed/oUDLgGB3uj0 114 2026-10-03T12:10:40+00:00 yes https://xdme.com/watch-book13-q013.html https://xdme.com/book13-thumbs/page-013.jpg Why Does Sunshine Feel Warm on Your Face Even When the Air Is Cold? Sunshine warms your skin because light carries energy. Your skin absorbs some of that energy as heat. The air can be cold, but the sunlight still warms you! https://socialmedia.xdme.com/tony/videos-book13/page-013.mp4 https://www.youtube.com/embed/AsYrWoQx85I 111 2026-10-03T12:10:41+00:00 yes https://xdme.com/watch-book13-q014.html https://xdme.com/book13-thumbs/page-014.jpg Why Can a Cardboard Solar Oven Cook with Only Sunshine? A solar oven uses mirrors or shiny foil to bounce extra sunlight onto a dark pan, and the box traps the warm air inside. That lets a cardboard box cook with only sunshine! The pan https://socialmedia.xdme.com/tony/videos-book13/page-014.mp4 https://www.youtube.com/embed/NY3FQ4wBAow 117 2026-10-03T12:10:42+00:00 yes https://xdme.com/watch-book13-q015.html https://xdme.com/book13-thumbs/page-015.jpg Why Does Snow Melt First Around a Dark Rock? Dark rocks soak up more of the Sun's light than bright snow does. They turn it into heat and melt the snow right next to them. That leaves a little hollow around the stone! https://socialmedia.xdme.com/tony/videos-book13/page-015.mp4 https://www.youtube.com/embed/dqigw2vFrxA 108 2026-10-03T12:10:44+00:00 yes https://xdme.com/watch-book13-q016.html https://xdme.com/book13-thumbs/page-016.jpg Why Do Houseplants Lean Toward a Window? Plants turn toward light because they use it to make food. A growth chemical in the stem moves to the shaded side, and the shaded cells grow longer. That bends the stem toward the https://socialmedia.xdme.com/tony/videos-book13/page-016.mp4 https://www.youtube.com/embed/PKTHRiu1MJw 117 2026-10-03T12:12:27+00:00 yes https://xdme.com/watch-book13-q017.html https://xdme.com/book13-thumbs/page-017.jpg Why Does the Bright Patch From a Window Slide Across the Floor? The Earth is spinning, so the Sun seems to move across the sky. The angle of the light through your window changes, and the bright patch slides across the floor. https://socialmedia.xdme.com/tony/videos-book13/page-017.mp4 https://www.youtube.com/embed/iwt3bduWMIY 111 2026-10-03T12:14:00+00:00 yes https://xdme.com/watch-book13-q018.html https://xdme.com/book13-thumbs/page-018.jpg Why Is a Cloudy Day Outside Still Brighter than a Lit Room Inside? The Sun is so powerful that even through thick clouds, daylight is much stronger than room lights. Outdoors on a cloudy day, the light can be 10 to 100 times brighter than a lamp i https://socialmedia.xdme.com/tony/videos-book13/page-018.mp4 https://www.youtube.com/embed/d63l26sr8Qo 116 2026-10-03T12:17:03+00:00 yes https://xdme.com/watch-book13-q019.html https://xdme.com/book13-thumbs/page-019.jpg Why Do Shadows Disappear on Cloudy Days? Direct sunlight comes from one small, bright spot, so it makes sharp shadows. Clouds spread the sunlight across the whole sky. Then light arrives from every direction, and shadows https://socialmedia.xdme.com/tony/videos-book13/page-019.mp4 https://www.youtube.com/embed/AYHXrpEsGDU 118 2026-10-03T12:19:36+00:00 yes https://xdme.com/watch-book13-q020.html https://xdme.com/book13-thumbs/page-020.jpg Why Does Your Shadow Stretch, Shrink, and Stretch Again as You Walk Past a Streetlamp? A streetlamp is one small light, and your shadow always points away from it. When you are far from the lamp, your shadow is long. As you walk close, it gets short and swings undern https://socialmedia.xdme.com/tony/videos-book13/page-020.mp4 https://www.youtube.com/embed/sXdxkFPhtxI 117 2026-10-03T12:22:40+00:00 yes https://xdme.com/watch-book13-q021.html https://xdme.com/book13-thumbs/page-021.jpg Why Does Your Hand Make a Giant Shadow When It Is Close to a Lamp? A lamp spreads its light out in all directions, like rays from a single point. If your hand is close to the lamp, it blocks a wide cone of light. So the shadow on the wall grows hu https://socialmedia.xdme.com/tony/videos-book13/page-021.mp4 https://www.youtube.com/embed/Jy8LHsjwwbQ 114 2026-10-03T12:25:12+00:00 yes https://xdme.com/watch-book13-q022.html https://xdme.com/book13-thumbs/page-022.jpg Why Can You See the Shadow of a Cloud Sliding Across a Field? A cloud blocks sunlight and casts a shadow on the ground below it. The wind pushes the cloud along, so its shadow glides across the field. The shadow is darkest right where the clo https://socialmedia.xdme.com/tony/videos-book13/page-022.mp4 https://www.youtube.com/embed/sIBBlkom5tY 118 2026-10-03T12:27:44+00:00 yes https://xdme.com/watch-book13-q023.html https://xdme.com/book13-thumbs/page-023.jpg Why Does Your Shadow Always Follow You? Your shadow is simply the place where your body blocks light. As you move, the blocked area moves with you. So your shadow stays attached to your feet and looks like it follows you https://socialmedia.xdme.com/tony/videos-book13/page-023.mp4 https://www.youtube.com/embed/MohE5iNz0MQ 114 2026-10-03T12:30:50+00:00 yes https://xdme.com/watch-book13-q024.html https://xdme.com/book13-thumbs/page-024.jpg Why Do Beams of Sunlight Fan Out From Behind a Cloud? Gaps in a cloud let sunlight shine through in beams. The beams look like they fan out from the cloud, but they are really parallel. Perspective fools our eyes into seeing them spre https://socialmedia.xdme.com/tony/videos-book13/page-024.mp4 https://www.youtube.com/embed/X9YijlRQuPQ 117 2026-10-03T12:33:56+00:00 yes https://xdme.com/watch-book13-q025.html https://xdme.com/book13-thumbs/page-025.jpg Why Do Tall Buildings Leave Long, Cool Shadows on City Streets? Tall buildings block the Sun, so their shadows fall across the street and make it cooler there. In winter, when the Sun is low, the shadows are especially long. Some streets stay i https://socialmedia.xdme.com/tony/videos-book13/page-025.mp4 https://www.youtube.com/embed/-xp1jPrW4P0 122 2026-10-03T12:36:59+00:00 yes https://xdme.com/watch-book13-q026.html https://xdme.com/book13-thumbs/page-026.jpg Why Do Red, Green, and Blue Lights Mix to Make White Light? Colored light mixes by adding. When red, green, and blue lights shine on the same spot, your eyes get all three signals at once. Your brain sees white! https://socialmedia.xdme.com/tony/videos-book13/page-026.mp4 https://www.youtube.com/embed/iRrhaIb94Ek 115 2026-10-03T12:40:33+00:00 yes https://xdme.com/watch-book13-q027.html https://xdme.com/book13-thumbs/page-027.jpg Why Do Paints Mix Differently From Colored Lights? Paint and light follow opposite rules. Paint mixes by taking colors away, but light mixes by adding colors together. That is why they act so differently! https://socialmedia.xdme.com/tony/videos-book13/page-027.mp4 https://www.youtube.com/embed/I43eL4lv6Xw 118 2026-10-03T12:43:35+00:00 yes https://xdme.com/watch-book13-q028.html https://xdme.com/book13-thumbs/page-028.jpg Why Can You Make Almost Any Color From Just Three Paints? Painters can mix a huge range of colors from just a few paints. School sets often start with red, yellow, and blue, and printers use cyan, magenta, and yellow. Add white and black, https://socialmedia.xdme.com/tony/videos-book13/page-028.mp4 https://www.youtube.com/embed/NmoLReY5WzE 115 2026-10-03T12:46:38+00:00 yes https://xdme.com/watch-book13-q029.html https://xdme.com/book13-thumbs/page-029.jpg Why Does Mixing All Your Paints Make a Muddy Brown? Every paint soaks up some colors of light. When you mix lots of paints, the mixture soaks up almost every color. Very little light bounces back, and you see a dull brown! https://socialmedia.xdme.com/tony/videos-book13/page-029.mp4 https://www.youtube.com/embed/yqnE6B5kYug 117 2026-10-03T12:49:10+00:00 yes https://xdme.com/watch-book13-q030.html https://xdme.com/book13-thumbs/page-030.jpg Why Does a Red Cellophane Sheet Change What You See? Red cellophane lets red light pass through and blocks most other colors. That changes which light reaches your eyes, so everything looks different through it! https://socialmedia.xdme.com/tony/videos-book13/page-030.mp4 https://www.youtube.com/embed/2kkOg7CVK-0 123 2026-10-03T12:52:13+00:00 yes https://xdme.com/watch-book13-q031.html https://xdme.com/book13-thumbs/page-031.jpg Why Do Colors Look Different Under Different Lamps? Different lamps give off different mixes of colors. A warm yellow bulb makes a lot of red and yellow light but little blue. So the same shirt can look different under each lamp! https://socialmedia.xdme.com/tony/videos-book13/page-031.mp4 https://www.youtube.com/embed/2oX1qN1iGYE 111 2026-10-03T12:54:47+00:00 yes https://xdme.com/watch-book13-q032.html https://xdme.com/book13-thumbs/page-032.jpg Why Do Some People See Some Colors Differently? Your eyes have three kinds of color-sensing cells called cones. Not everyone's cones work in exactly the same way. Some people see certain colors, often reds and greens, as more al https://socialmedia.xdme.com/tony/videos-book13/page-032.mp4 https://www.youtube.com/embed/JeUIZPTcf-s 117 2026-10-03T12:57:49+00:00 yes https://xdme.com/watch-book13-q033.html https://xdme.com/book13-thumbs/page-033.jpg Why Do Screens Use Only Red, Green, and Blue Dots? A screen is covered in tiny dots, called pixels, that shine red, green, or blue. Your eyes blend the three lights together. Making each dot brighter or dimmer lets the screen show https://socialmedia.xdme.com/tony/videos-book13/page-033.mp4 https://www.youtube.com/embed/R7SDNuarZuU 117 2026-10-03T13:00:54+00:00 yes https://xdme.com/watch-book13-q034.html https://xdme.com/book13-thumbs/page-034.jpg How Does the Color of Paper Change How Much Light Bounces Back? White paper reflects almost all colors of light, so it looks white. Black paper soaks up almost all colors, so very little light comes back to your eyes. Colored paper reflects mos https://socialmedia.xdme.com/tony/videos-book13/page-034.mp4 https://www.youtube.com/embed/KkjAbnDNU6o 119 2026-10-03T13:03:35+00:00 yes https://xdme.com/watch-book13-q035.html https://xdme.com/book13-thumbs/page-035.jpg Why Do Two Colored Flashlights Make Colored Shadows? Each colored light casts its own shadow, and the other light lights it up. If a red light and a green light shine on an object, the spot blocked from red is lit only by green. So t https://socialmedia.xdme.com/tony/videos-book13/page-035.mp4 https://www.youtube.com/embed/y7Aygg-gdQE 113 2026-10-03T13:06:38+00:00 yes https://xdme.com/watch-book13-q036.html https://xdme.com/book13-thumbs/page-036.jpg Why Does a Spinning Color Wheel Turn White? Your eyes cannot keep up with colors flashing past very quickly. On a spinning wheel with all the rainbow colors, your eye blends them together. You see a pale, whitish gray! https://socialmedia.xdme.com/tony/videos-book13/page-036.mp4 https://www.youtube.com/embed/ZIeRxrifMF8 114 2026-10-03T13:09:10+00:00 yes https://xdme.com/watch-book13-q037.html https://xdme.com/book13-thumbs/page-037.jpg Why Does the Same Gray Look Lighter or Darker on Different Backgrounds? Your brain decides how light or dark something looks by comparing it with the things around it. A gray square looks lighter on a dark background and darker on a light one. It can b https://socialmedia.xdme.com/tony/videos-book13/page-037.mp4 https://www.youtube.com/embed/_bve_DQy89Y 114 2026-10-03T13:12:13+00:00 yes https://xdme.com/watch-book13-q038.html https://xdme.com/book13-thumbs/page-038.jpg Why Do Secret Decoder Windows Reveal Hidden Messages? A decoder window is a sheet of red plastic. It lets red light through, so red scribbles seem to vanish into the paper. Dark or green lines look black, so hidden words appear! https://socialmedia.xdme.com/tony/videos-book13/page-038.mp4 https://www.youtube.com/embed/45oetcJea2Y 109 2026-10-03T13:15:17+00:00 yes https://xdme.com/watch-book13-q039.html https://xdme.com/book13-thumbs/page-039.jpg Why Does Adding White Paint Make a Color Lighter? White paint reflects almost all light. Adding it to a color means more light bounces back, so the color looks paler and lighter. Artists call this a tint! https://socialmedia.xdme.com/tony/videos-book13/page-039.mp4 https://www.youtube.com/embed/OTzMfQUgeys 108 2026-10-03T13:17:50+00:00 yes https://xdme.com/watch-book13-q040.html https://xdme.com/book13-thumbs/page-040.jpg Why Does Wet Sand Look Darker than Dry Sand? Dry sand scatters light off every grain, so it looks pale. Wet sand has a thin film of water around each grain. More light slips inside, where it gets absorbed, so the sand looks d https://socialmedia.xdme.com/tony/videos-book13/page-040.mp4 https://www.youtube.com/embed/HELrarU98sg 113 2026-10-03T13:20:23+00:00 yes https://xdme.com/watch-book13-q041.html https://xdme.com/book13-thumbs/page-041.jpg Why Do Colors on a Phone Screen Look Different From Colors on Paper? A screen makes its own light, using tiny red, green, and blue dots. Paper only reflects the light of the room. That is why the same picture can look different on each! https://socialmedia.xdme.com/tony/videos-book13/page-041.mp4 https://www.youtube.com/embed/i2-v_qqmF1w 120 2026-10-03T13:23:55+00:00 yes https://xdme.com/watch-book13-q042.html https://xdme.com/book13-thumbs/page-042.jpg Why Are Roofs in Hot Places Often Painted White? White roofs reflect most of the Sun's light instead of soaking it up. Dark roofs absorb sunlight as heat. So white roofs keep buildings cooler inside! https://socialmedia.xdme.com/tony/videos-book13/page-042.mp4 https://www.youtube.com/embed/CSuIk4zOgAo 116 2026-10-03T13:26:28+00:00 yes https://xdme.com/watch-book13-q043.html https://xdme.com/book13-thumbs/page-043.jpg Why Do Old Posters in Sunny Windows Fade to Blue? Sunlight, especially ultraviolet light, slowly breaks apart the molecules that give inks and dyes their colors. Some dyes break down faster than others. Often red and yellow fade f https://socialmedia.xdme.com/tony/videos-book13/page-043.mp4 https://www.youtube.com/embed/2ZbcEt0kRA0 124 2026-10-03T13:29:31+00:00 yes https://xdme.com/watch-book13-q044.html https://xdme.com/book13-thumbs/page-044.jpg Why Do Magicians Hang Black Cloth Behind Their Tricks? Black velvet soaks up almost all the light that hits it. It reflects very little back to your eyes, so it looks like empty darkness. Things dressed in black in front of it seem to https://socialmedia.xdme.com/tony/videos-book13/page-044.mp4 https://www.youtube.com/embed/v2UnZyLXdB4 119 2026-10-03T13:32:34+00:00 yes https://xdme.com/watch-book13-q045.html https://xdme.com/book13-thumbs/page-045.jpg Why Can’t You Make Black by Mixing Colored Lights? When you mix colored lights, every new light adds more brightness. So the mix gets lighter, not darker. Black is the absence of light, so adding lights can never make it! https://socialmedia.xdme.com/tony/videos-book13/page-045.mp4 https://www.youtube.com/embed/JsHiMUeMqN8 113 2026-10-03T13:35:38+00:00 yes https://xdme.com/watch-book13-q046.html https://xdme.com/book13-thumbs/page-046.jpg Why Do Newspaper Pictures Turn Into Tiny Dots Under a Magnifier? Newspaper photos are printed with tiny dots of ink in different sizes. From far away, your eyes blend the dots into smooth shades. Up close with a magnifier, you can see the dots! https://socialmedia.xdme.com/tony/videos-book13/page-046.mp4 https://www.youtube.com/embed/beCI56RRHDA 122 2026-10-03T13:38:40+00:00 yes https://xdme.com/watch-book13-q047.html https://xdme.com/book13-thumbs/page-047.jpg Why Can Bees See Patterns on Flowers That We Cannot? Bees and many other insects can see ultraviolet light, which humans cannot. Many flowers have patterns that only show up in ultraviolet. To a bee, a plain flower may carry a bright https://socialmedia.xdme.com/tony/videos-book13/page-047.mp4 https://www.youtube.com/embed/iBg_4cn9Xf0 122 2026-10-03T13:41:13+00:00 yes https://xdme.com/watch-book13-q048.html https://xdme.com/book13-thumbs/page-048.jpg Why Does a Red Apple Look Almost Black Under a Green Light? A red apple looks red because it reflects red light and absorbs the rest. A green light has no red in it, so there is nothing for the apple to reflect. The apple looks dark gray or https://socialmedia.xdme.com/tony/videos-book13/page-048.mp4 https://www.youtube.com/embed/lVV-l0ClreQ 114 2026-10-03T13:43:56+00:00 yes https://xdme.com/watch-book13-q049.html https://xdme.com/book13-thumbs/page-049.jpg Why Do Artists Use a Color Wheel to Pick Colors That Look Good Together? A color wheel arranges colors in a circle. Neighbors blend smoothly and opposites sit across from each other. That makes it easy to pick colors that look good together! https://socialmedia.xdme.com/tony/videos-book13/page-049.mp4 https://www.youtube.com/embed/fXKMQU7uHzU 121 2026-10-03T13:47:02+00:00 yes https://xdme.com/watch-book13-q050.html https://xdme.com/book13-thumbs/page-050.jpg Why Does Paint Change Color a Little as It Dries? Wet paint is a mix of tiny pigment bits floating in liquid. As the water evaporates, the paint layer changes how light moves through it. That makes the color shift a little as it d https://socialmedia.xdme.com/tony/videos-book13/page-050.mp4 https://www.youtube.com/embed/Dooinvyjmns 118 2026-10-03T13:49:47+00:00 yes https://xdme.com/watch-book13-q051.html https://xdme.com/book13-thumbs/page-051.jpg Why Can You See Yourself in a Mirror but Not in a Wall? A mirror is so smooth that light bounces off it in an orderly way, which makes a clear picture of you. A wall looks smooth, but up close it is full of tiny bumps. Those bumps send https://socialmedia.xdme.com/tony/videos-book13/page-051.mp4 https://www.youtube.com/embed/iki0PyhOvdI 109 2026-10-03T13:52:21+00:00 yes https://xdme.com/watch-book13-q052.html https://xdme.com/book13-thumbs/page-052.jpg Why Does Light Bounce Off a Mirror at the Same Angle It Hits? Light bounces off a mirror at the same angle it came in, just like a ball bouncing off a wall. Scientists call this the law of reflection. A low beam leaves low, and a steep beam l https://socialmedia.xdme.com/tony/videos-book13/page-052.mp4 https://www.youtube.com/embed/scFdlqqizDI 112 2026-10-03T13:55:23+00:00 yes https://xdme.com/watch-book13-q053.html https://xdme.com/book13-thumbs/page-053.jpg Why Can a Periscope Let You See Over a Wall? A periscope uses two mirrors set at a slant to pass light around an obstacle. Light from the scene goes down the tube and into your eye. That lets you see over a wall without lifti https://socialmedia.xdme.com/tony/videos-book13/page-053.mp4 https://www.youtube.com/embed/odJVnFrly5Q 108 2026-10-03T13:57:57+00:00 yes https://xdme.com/watch-book13-q054.html https://xdme.com/book13-thumbs/page-054.jpg Why Do Two Mirrors Facing Each Other Show Endless Copies? Two mirrors facing each other show endless copies because each mirror reflects the other again and again. The copies line up like a tunnel, each one smaller than the last. In theor https://socialmedia.xdme.com/tony/videos-book13/page-054.mp4 https://www.youtube.com/embed/xSZXXSW9Lcs 113 2026-10-03T14:00:29+00:00 yes https://xdme.com/watch-book13-q055.html https://xdme.com/book13-thumbs/page-055.jpg Why Does Your Face Look Upside Down in the Back of a Spoon? A spoon is curved like a tiny mirror. The cupped inside bends light so that a face far away looks upside down. The back of the spoon curves outward, so your face stays upright but https://socialmedia.xdme.com/tony/videos-book13/page-055.mp4 https://www.youtube.com/embed/GCGGJKbCtZ8 107 2026-10-03T14:03:02+00:00 yes https://xdme.com/watch-book13-q056.html https://xdme.com/book13-thumbs/page-056.jpg Why Do Car Side Mirrors Say Objects Are Closer than They Appear? Some car side mirrors curve outward, which gives drivers a wider view of the road. But a curved mirror makes everything in it look smaller. Smaller things seem farther away, so the https://socialmedia.xdme.com/tony/videos-book13/page-056.mp4 https://www.youtube.com/embed/tY-e4JeX0hA 109 2026-10-03T14:05:35+00:00 yes https://xdme.com/watch-book13-q057.html https://xdme.com/book13-thumbs/page-057.jpg Why Does a Makeup Mirror Make Your Face Look Bigger? A makeup or shaving mirror curves inward, like the inside of a spoon. When your face is close, the curve spreads out the reflection into a big, upright picture. Move farther back, https://socialmedia.xdme.com/tony/videos-book13/page-057.mp4 https://www.youtube.com/embed/_l66b_1zHYE 111 2026-10-03T14:08:16+00:00 yes https://xdme.com/watch-book13-q058.html https://xdme.com/book13-thumbs/page-058.jpg Why Does a Swimming Pool Look Shallower than It Really Is? Light bends when it leaves water and enters the air. Your brain assumes light always travels in a straight line, so it places the bottom of the pool higher than it really is. That https://socialmedia.xdme.com/tony/videos-book13/page-058.mp4 https://www.youtube.com/embed/fI4Q4-5gL9I 107 2026-10-03T14:10:50+00:00 yes https://xdme.com/watch-book13-q059.html https://xdme.com/book13-thumbs/page-059.jpg Why Does a Coin Appear When You Pour Water Into a Bowl? A coin in an empty bowl can hide behind the rim. Pour in water, and light from the coin bends as it leaves the water. Now it clears the rim, and your brain thinks the coin floated https://socialmedia.xdme.com/tony/videos-book13/page-059.mp4 https://www.youtube.com/embed/d86aGg6Gny0 105 2026-10-03T14:13:52+00:00 yes https://xdme.com/watch-book13-q060.html https://xdme.com/book13-thumbs/page-060.jpg Why Does a Glass of Water Flip an Arrow Upside Down? A tall glass of water is curved like a lens, so it bends the light passing through it. At the right distance, the picture flips from side to side. An arrow pointing left suddenly p https://socialmedia.xdme.com/tony/videos-book13/page-060.mp4 https://www.youtube.com/embed/xWc2kfRIij0 107 2026-10-03T14:16:25+00:00 yes https://xdme.com/watch-book13-q061.html https://xdme.com/book13-thumbs/page-061.jpg Why Does a Magnifying Glass Make Things Look Bigger? A magnifying glass is a lens that is thicker in the middle than at the edges. It bends the light from a small thing so the picture spreads wider across your eye. Your brain thinks https://socialmedia.xdme.com/tony/videos-book13/page-061.mp4 https://www.youtube.com/embed/mxTWzDJTSG8 111 2026-10-03T14:18:58+00:00 yes https://xdme.com/watch-book13-q062.html https://xdme.com/book13-thumbs/page-062.jpg Why Should You Never Play with a Magnifying Glass in the Sun? A magnifying glass can gather sunlight into one small, very bright, very hot spot. That spot can scorch paper, leaves, and skin, and it can even start a fire. Never look at the Sun https://socialmedia.xdme.com/tony/videos-book13/page-062.mp4 https://www.youtube.com/embed/0foCmQCByRc 114 2026-10-03T14:22:00+00:00 yes https://xdme.com/watch-book13-q063.html https://xdme.com/book13-thumbs/page-063.jpg Why Do Some Lenses Make Things Look Smaller? A lens that is thinner in the middle than at the edges spreads light out. That makes things look smaller. It also lets you see a much wider scene. https://socialmedia.xdme.com/tony/videos-book13/page-063.mp4 https://www.youtube.com/embed/Be0CSScFGzk 110 2026-10-03T14:25:03+00:00 yes https://xdme.com/watch-book13-q064.html https://xdme.com/book13-thumbs/page-064.jpg Why Can a Water Drop on a Leaf Work Like a Tiny Lens? A small drop of water has a smooth, curved top. That shape bends light just like a tiny magnifying lens. Letters under a drop look bigger, and dew drops can make leaf veins seem la https://socialmedia.xdme.com/tony/videos-book13/page-064.mp4 https://www.youtube.com/embed/2LWUg-7XG5U 109 2026-10-03T14:28:09+00:00 yes https://xdme.com/watch-book13-q065.html https://xdme.com/book13-thumbs/page-065.jpg How Does a Microscope Show Things Too Small to See? A microscope uses two lenses, one close to the object and one near your eye. Together they magnify the picture in two steps. That lets you see things too small for your eyes alone. https://socialmedia.xdme.com/tony/videos-book13/page-065.mp4 https://www.youtube.com/embed/tFb07kI82nM 109 2026-10-03T14:30:40+00:00 yes https://xdme.com/watch-book13-q066.html https://xdme.com/book13-thumbs/page-066.jpg Why Is the Word Ambulance Written Backward on the Front of the Van? A mirror flips writing from left to right. AMBULANCE is printed backward on the front of the van. So a driver looking in the rear-view mirror reads it the right way round. https://socialmedia.xdme.com/tony/videos-book13/page-066.mp4 https://www.youtube.com/embed/3HJlo8WpL3A 106 2026-10-03T14:33:43+00:00 yes https://xdme.com/watch-book13-q067.html https://xdme.com/book13-thumbs/page-067.jpg Why Can You See Your Room Reflected in a Window at Night? Window glass lets most light through, but it also reflects a little, like a very faint mirror. In the daytime, the light from outside is much stronger than the reflection. At night https://socialmedia.xdme.com/tony/videos-book13/page-067.mp4 https://www.youtube.com/embed/CWlfT0UEDHk 109 2026-10-03T14:36:46+00:00 yes https://xdme.com/watch-book13-q068.html https://xdme.com/book13-thumbs/page-068.jpg Why Can Some Windows Look Like Mirrors From the Outside in the Daytime? Mirror-like windows have a thin metal coating that reflects some light and lets some through. Outside on a bright day, the reflection of the sky is brighter than the dim light comi https://socialmedia.xdme.com/tony/videos-book13/page-068.mp4 https://www.youtube.com/embed/RXek7Et28sY 107 2026-10-03T14:39:54+00:00 yes https://xdme.com/watch-book13-q069.html https://xdme.com/book13-thumbs/page-069.jpg Why Does a Calm Lake Show a Mirror Picture and a Windy Lake Does Not? Still water is flat, so it reflects light in an orderly way and makes a clear, upside-down picture. Wind and ripples tilt the surface into many little slopes. Each slope points a d https://socialmedia.xdme.com/tony/videos-book13/page-069.mp4 https://www.youtube.com/embed/LUpIh5Stfz8 114 2026-10-03T14:43:27+00:00 yes https://xdme.com/watch-book13-q070.html https://xdme.com/book13-thumbs/page-070.jpg Why Do Things Look Bigger and Closer Underwater? Light bends when it goes from water to air. A diving mask keeps a pocket of air in front of your eyes, so light bends as it enters the mask. That makes things look closer and bigge https://socialmedia.xdme.com/tony/videos-book13/page-070.mp4 https://www.youtube.com/embed/CgELEVnE1SU 107 2026-10-03T14:46:08+00:00 yes https://xdme.com/watch-book13-q071.html https://xdme.com/book13-thumbs/page-071.jpg Why Does a Lens Bring Light Together at One Spot? A lens is curved so that rays of light passing through it bend toward each other. Rays from a faraway scene all meet at one place, called the focus. A sheet of paper held there sho https://socialmedia.xdme.com/tony/videos-book13/page-071.mp4 https://www.youtube.com/embed/_prHTQ9Nf6s 110 2026-10-03T14:49:12+00:00 yes https://xdme.com/watch-book13-q072.html https://xdme.com/book13-thumbs/page-072.jpg Why Does a Kaleidoscope Make Endless Patterns? A kaleidoscope has two or three mirrors set at an angle inside a tube. Bits of colored glass tumble at one end, and the mirrors reflect them again and again. Your eye sees a wheel https://socialmedia.xdme.com/tony/videos-book13/page-072.mp4 https://www.youtube.com/embed/6ms1_ZT8ayg 113 2026-10-03T14:52:15+00:00 yes https://xdme.com/watch-book13-q073.html https://xdme.com/book13-thumbs/page-073.jpg Why Do Funhouse Mirrors Make You Look Wide or Skinny? Funhouse mirrors are curved and bumpy, so each part bends the reflection differently. A bump pushing outward makes you look skinnier there. A dip curving inward makes you look wide https://socialmedia.xdme.com/tony/videos-book13/page-073.mp4 https://www.youtube.com/embed/endPCmXAhMo 112 2026-10-03T14:56:48+00:00 yes https://xdme.com/watch-book13-q074.html https://xdme.com/book13-thumbs/page-074.jpg Why Do You Only Need a Half-Length Mirror to See Your Whole Body? To see your whole body, a mirror only needs to be half as tall as you are. That is true no matter how far away you stand. Light from your head and feet each reaches your eyes by a https://socialmedia.xdme.com/tony/videos-book13/page-074.mp4 https://www.youtube.com/embed/7U61Zu5TM8Q 101 2026-10-03T15:02:21+00:00 yes https://xdme.com/watch-book13-q075.html https://xdme.com/book13-thumbs/page-075.jpg Why Do Shiny Round Balls Show the Whole Room in a Tiny Picture? A shiny curved ball acts like a convex mirror that reflects light from nearly every direction. In its small surface you can see a tiny, squished picture of the whole room. You can https://socialmedia.xdme.com/tony/videos-book13/page-075.mp4 https://www.youtube.com/embed/lVo3h2RaNX4 109 2026-10-03T15:06:55+00:00 yes https://xdme.com/watch-book13-q076.html https://xdme.com/book13-thumbs/page-076.jpg Why Can You See Through Glass but Not Through Wood? Light passes through glass because the atoms in glass do not soak up visible light. Wood soaks up or scatters nearly all the light that hits it, so none gets through. Things that l https://socialmedia.xdme.com/tony/videos-book13/page-076.mp4 https://www.youtube.com/embed/_YoPozEE7Ac 110 2026-10-03T12:10:45+00:00 yes https://xdme.com/watch-book13-q077.html https://xdme.com/book13-thumbs/page-077.jpg Why Does Frosted Glass Hide Shapes but Still Let Light In? Frosted glass has a rough surface covered in tiny bumps. Light still gets through, but each bump bends it in a different direction, so the picture gets scrambled. You see a soft gl https://socialmedia.xdme.com/tony/videos-book13/page-077.mp4 https://www.youtube.com/embed/vBLwDptd1Qg 116 2026-10-03T12:10:47+00:00 yes https://xdme.com/watch-book13-q078.html https://xdme.com/book13-thumbs/page-078.jpg Why Does a Sheet of Paper Glow When You Hold a Flashlight Behind It? Paper is made of tiny fibers with air gaps between them. Light going in bounces around among the fibers and spreads out, and some of it comes out the other side. The paper glows so https://socialmedia.xdme.com/tony/videos-book13/page-078.mp4 https://www.youtube.com/embed/C6ivcoJyu9g 112 2026-10-03T12:10:48+00:00 yes https://xdme.com/watch-book13-q079.html https://xdme.com/book13-thumbs/page-079.jpg Why Does Wet Paper Turn See-Through? Dry paper scatters light at every air gap between its fibers. Water or oil fills those gaps and bends light less, so more light slips straight through. The wet patch lets more ligh https://socialmedia.xdme.com/tony/videos-book13/page-079.mp4 https://www.youtube.com/embed/5we2E5q-gTU 109 2026-10-03T12:11:01+00:00 yes https://xdme.com/watch-book13-q080.html https://xdme.com/book13-thumbs/page-080.jpg Why Are Some Things Shiny and Others Dull? Smooth surfaces reflect light in one direction, so you see a bright, glossy shine. Rough surfaces scatter light in all directions, so they look dull or matte. A polished shoe is sh https://socialmedia.xdme.com/tony/videos-book13/page-080.mp4 https://www.youtube.com/embed/sB2xo3I3WQ8 112 2026-10-03T12:11:02+00:00 yes https://xdme.com/watch-book13-q081.html https://xdme.com/book13-thumbs/page-081.jpg Why Are Metals So Shiny? Metals contain lots of electrons that are free to move around. When light hits metal, these electrons shake and send most of the light right back out. That bounced light is what gi https://socialmedia.xdme.com/tony/videos-book13/page-081.mp4 https://www.youtube.com/embed/01F7aAnqIUw 113 2026-10-03T12:11:14+00:00 yes https://xdme.com/watch-book13-q082.html https://xdme.com/book13-thumbs/page-082.jpg Why Does Polishing Make a Spoon Shinier? Rubbing a spoon smooths out tiny scratches and bumps. A smoother surface reflects light in an orderly way, so it shines. The smoother it gets, the more it looks like a little mirro https://socialmedia.xdme.com/tony/videos-book13/page-082.mp4 https://www.youtube.com/embed/7u8u4czB3V4 111 2026-10-03T12:11:16+00:00 yes https://xdme.com/watch-book13-q083.html https://xdme.com/book13-thumbs/page-083.jpg Why Do Air Bubbles in Water Look Silvery? Air bubbles in water look silvery because light inside the water hits the bubble's edge at a steep angle. Instead of passing out, it bounces back. The bubble acts like a tiny round https://socialmedia.xdme.com/tony/videos-book13/page-083.mp4 https://www.youtube.com/embed/tHEu26HjN4c 111 2026-10-03T12:11:17+00:00 yes https://xdme.com/watch-book13-q084.html https://xdme.com/book13-thumbs/page-084.jpg Why Does Frost Sparkle? Frost and fresh snow are made of tiny ice crystals with flat, shiny faces. Each face works like a little mirror. When you move, different faces tilt toward your eyes, and each flas https://socialmedia.xdme.com/tony/videos-book13/page-084.mp4 https://www.youtube.com/embed/mxXyjl2YTNQ 114 2026-10-03T12:11:18+00:00 yes https://xdme.com/watch-book13-q085.html https://xdme.com/book13-thumbs/page-085.jpg Why Do Gemstones Sparkle More When They Are Cut? A gemstone is cut with flat surfaces called facets. Light enters the top, bounces from facet to facet inside the stone, and exits the top again. The stone also splits the light int https://socialmedia.xdme.com/tony/videos-book13/page-085.mp4 https://www.youtube.com/embed/SjYh0Y3FKVs 116 2026-10-03T12:11:19+00:00 yes https://xdme.com/watch-book13-q086.html https://xdme.com/book13-thumbs/page-086.jpg Why Do Glitter and Sequins Flash When You Move? Glitter and sequins are made of lots of tiny flat, shiny pieces. They all point in slightly different directions. When you move, each piece takes a turn bouncing light into your ey https://socialmedia.xdme.com/tony/videos-book13/page-086.mp4 https://www.youtube.com/embed/fkSX22LKa08 111 2026-10-03T12:11:21+00:00 yes https://xdme.com/watch-book13-q087.html https://xdme.com/book13-thumbs/page-087.jpg Why Do CDs and DVDs Shimmer with Colors? A CD or DVD has a spiral track of super-tiny grooves, spaced very close together. These grooves split white light into its colors. Which colors you see depends on the angle you loo https://socialmedia.xdme.com/tony/videos-book13/page-087.mp4 https://www.youtube.com/embed/I3Mc_h5oxl0 118 2026-10-03T12:11:23+00:00 yes https://xdme.com/watch-book13-q088.html https://xdme.com/book13-thumbs/page-088.jpg Why Does the Inside of a Seashell Shimmer with Colors? The inside of many shells, called mother-of-pearl, is built from lots of super-thin layers of a chalky material. Light bounces off the top and bottom of each layer, and some colors https://socialmedia.xdme.com/tony/videos-book13/page-088.mp4 https://www.youtube.com/embed/zHUMXXPxZ5I 114 2026-10-03T12:11:24+00:00 yes https://xdme.com/watch-book13-q089.html https://xdme.com/book13-thumbs/page-089.jpg Why Does a Wet Leaf Look Shinier than a Dry One? A dry leaf has tiny bumps that scatter light, so it looks dull. Water fills in the bumps and makes a smooth, clear layer on top. The smooth layer reflects light in one direction, l https://socialmedia.xdme.com/tony/videos-book13/page-089.mp4 https://www.youtube.com/embed/l8zgjftrmNI 112 2026-10-03T12:11:25+00:00 yes https://xdme.com/watch-book13-q090.html https://xdme.com/book13-thumbs/page-090.jpg Why Does Glare Make a Shiny Page Hard to Read? A glossy page acts like a mirror and bounces the lamp's light straight toward your eyes. That bright reflection, called glare, is stronger than the light from the ink. So the words https://socialmedia.xdme.com/tony/videos-book13/page-090.mp4 https://www.youtube.com/embed/Le-h7HKFecw 111 2026-10-03T12:11:26+00:00 yes https://xdme.com/watch-book13-q091.html https://xdme.com/book13-thumbs/page-091.jpg Why Do Phone Screens Turn Into Mirrors in Bright Sunshine? A phone screen makes its own light, but the glass also reflects light from the sky or a window. Outdoors in sunshine, the reflected light can be brighter than the light from the sc https://socialmedia.xdme.com/tony/videos-book13/page-091.mp4 https://www.youtube.com/embed/UMwqlODkkxk 109 2026-10-03T12:12:29+00:00 yes https://xdme.com/watch-book13-q092.html https://xdme.com/book13-thumbs/page-092.jpg Why Can a Pond Look Like a Mirror When You Look From Low Down? When you look at water from low down, at a shallow angle, almost all of the light bounces off the surface like from a mirror. When you look from high above, more light passes throu https://socialmedia.xdme.com/tony/videos-book13/page-092.mp4 https://www.youtube.com/embed/2jqfzf5EBGY 106 2026-10-03T12:14:02+00:00 yes https://xdme.com/watch-book13-q093.html https://xdme.com/book13-thumbs/page-093.jpg Why Is Muddy Water Cloudy? Muddy water is full of tiny bits of dirt that float around. Each bit bounces some of the light in a new direction, so light gets scattered before it can travel far. You cannot see https://socialmedia.xdme.com/tony/videos-book13/page-093.mp4 https://www.youtube.com/embed/ruh27sjYkfQ 109 2026-10-03T12:17:05+00:00 yes https://xdme.com/watch-book13-q094.html https://xdme.com/book13-thumbs/page-094.jpg Why Does Milk Look White When Water Is Clear? Milk is mostly water with tiny droplets of fat and bits of protein floating in it. These specks bounce every color of light in every direction. Mixed colors reach your eyes togethe https://socialmedia.xdme.com/tony/videos-book13/page-094.mp4 https://www.youtube.com/embed/8lAY9DGNaNU 109 2026-10-03T12:19:38+00:00 yes https://xdme.com/watch-book13-q095.html https://xdme.com/book13-thumbs/page-095.jpg Why Is the Foam on a Dark Drink White? Foam is made of many tiny bubbles, each with a very thin skin of liquid. Light bounces off all those skins in every direction, and none of it gets absorbed before it comes back out https://socialmedia.xdme.com/tony/videos-book13/page-095.mp4 https://www.youtube.com/embed/jKb6QJyq7n0 111 2026-10-03T12:22:09+00:00 yes https://xdme.com/watch-book13-q096.html https://xdme.com/book13-thumbs/page-096.jpg Why Is Table Salt White When One Crystal Is Clear? A single grain of salt is a tiny clear crystal. But a pile of grains has lots of surfaces that bounce light in every direction. So many bounces scramble the light, and the pile loo https://socialmedia.xdme.com/tony/videos-book13/page-096.mp4 https://www.youtube.com/embed/N58LqLtPMDA 111 2026-10-03T12:25:13+00:00 yes https://xdme.com/watch-book13-q097.html https://xdme.com/book13-thumbs/page-097.jpg Why Are Some Plastics Clear and Others Cloudy? Clear plastics have molecules arranged so that light can pass through without much scattering. Cloudy plastics have tiny crystals or added particles that bounce light around. Soda https://socialmedia.xdme.com/tony/videos-book13/page-097.mp4 https://www.youtube.com/embed/QjbUCoopjvE 117 2026-10-03T12:27:48+00:00 yes https://xdme.com/watch-book13-q098.html https://xdme.com/book13-thumbs/page-098.jpg Why Do Some Windows Have a Thin, Shiny Coating? Some windows have a coating that is thinner than a hair. It lets visible light pass through but reflects heat rays. In winter, it keeps heat in the room, and in summer, it keeps th https://socialmedia.xdme.com/tony/videos-book13/page-098.mp4 https://www.youtube.com/embed/pSG8ekff3c0 110 2026-10-03T12:30:54+00:00 yes https://xdme.com/watch-book13-q099.html https://xdme.com/book13-thumbs/page-099.jpg Why Does Crinkled Foil Sparkle in Every Direction? Smooth foil acts like a mirror, sending light in one direction. Crinkled foil has lots of tiny flat patches, all pointing in different directions. Each one flashes light somewhere https://socialmedia.xdme.com/tony/videos-book13/page-099.mp4 https://www.youtube.com/embed/gVjvzprn5aw 115 2026-10-03T12:33:25+00:00 yes https://xdme.com/watch-book13-q100.html https://xdme.com/book13-thumbs/page-100.jpg Why Do Very Dark Materials Like Velvet Seem to Swallow Light? Black velvet is made of tiny upright fibers. Light that enters gets trapped between them and bounces around until it is absorbed. Very little light comes back out, so the velvet lo https://socialmedia.xdme.com/tony/videos-book13/page-100.mp4 https://www.youtube.com/embed/k6dIbp1W9Oc 116 2026-10-03T12:36:28+00:00 yes https://xdme.com/watch-book13-q101.html https://xdme.com/book13-thumbs/page-101.jpg Why Does a Laser Pointer Make a Tiny Dot Instead of a Wide Beam? A laser pointer makes a tiny dot because its light is very organized! All of it is one color and travels together in the same direction, unlike a flashlight's wide cone. Never poin https://socialmedia.xdme.com/tony/videos-book13/page-101.mp4 https://www.youtube.com/embed/-TZeoCEpdXQ 111 2026-10-03T12:40:01+00:00 yes https://xdme.com/watch-book13-q102.html https://xdme.com/book13-thumbs/page-102.jpg Why Must You Never Shine a Laser Pointer at Anyone's Eyes, a Plane, or an Animal? A laser pointer packs lots of light into a tiny spot, so it is a tool and not a toy! Never shine one at eyes, planes, or animals. Safety rules keep every eye healthy. https://socialmedia.xdme.com/tony/videos-book13/page-102.mp4 https://www.youtube.com/embed/LDBIAYQiNq0 109 2026-10-03T12:43:04+00:00 yes https://xdme.com/watch-book13-q103.html https://xdme.com/book13-thumbs/page-103.jpg Why Does a Projector Turn a Tiny Picture Into a Huge One? A projector turns a tiny picture into a huge one by shining light through it! A lens spreads the light across a big screen and keeps the picture sharp. The bigger the picture, the https://socialmedia.xdme.com/tony/videos-book13/page-103.mp4 https://www.youtube.com/embed/Jn1LDS6wlkI 109 2026-10-03T12:46:07+00:00 yes https://xdme.com/watch-book13-q104.html https://xdme.com/book13-thumbs/page-104.jpg Why Does a Flip Book Make Pictures Move? A flip book makes pictures move because your brain fills in the gaps! Each page is a little different, and your eyes hold on to each picture for a moment. Flip fast enough and the https://socialmedia.xdme.com/tony/videos-book13/page-104.mp4 https://www.youtube.com/embed/4QYjWh08DVE 114 2026-10-03T12:49:11+00:00 yes https://xdme.com/watch-book13-q105.html https://xdme.com/book13-thumbs/page-105.jpg Why Do Hologram Stickers Change as You Tilt Them? A hologram sticker changes as you tilt it because of super-tiny ridges! The ridges bend different colors of light in different directions. Tilt the sticker, and your eyes catch dif https://socialmedia.xdme.com/tony/videos-book13/page-105.mp4 https://www.youtube.com/embed/V6FpYeIEgVA 116 2026-10-03T12:52:15+00:00 yes https://xdme.com/watch-book13-q106.html https://xdme.com/book13-thumbs/page-106.jpg How Do Optical Fibers Trap Light Inside a Thread? An optical fiber is a thin thread of glass or clear plastic that traps light inside! The light bounces along the inside wall, again and again. So it follows every bend. https://socialmedia.xdme.com/tony/videos-book13/page-106.mp4 https://www.youtube.com/embed/PVZJcHhGTwU 119 2026-10-03T12:55:18+00:00 yes https://xdme.com/watch-book13-q107.html https://xdme.com/book13-thumbs/page-107.jpg What Is Infrared Light, and Why Can We Feel It but Not See It? Infrared light has waves a little longer than red light, so our eyes cannot see it! But warm things give it off, and we feel it as heat. You give off infrared light too! https://socialmedia.xdme.com/tony/videos-book13/page-107.mp4 https://www.youtube.com/embed/D7O_Q6qde0I 112 2026-10-03T12:57:51+00:00 yes https://xdme.com/watch-book13-q108.html https://xdme.com/book13-thumbs/page-108.jpg Why Do Streetlights Switch on by Themselves at Dusk? A streetlight switches on by itself because it has a small light sensor! In daylight, the sensor keeps the lamp off. When it gets dark, the lamp turns on. https://socialmedia.xdme.com/tony/videos-book13/page-108.mp4 https://www.youtube.com/embed/2yYomp0FUBk 110 2026-10-03T13:00:23+00:00 yes https://xdme.com/watch-book13-q109.html https://xdme.com/book13-thumbs/page-109.jpg How Does a Solar-Powered Calculator Work Without a Battery? A solar calculator works without a battery because it makes electricity from light! A solar cell gives off a tiny bit of electricity when light hits it. A calculator needs so littl https://socialmedia.xdme.com/tony/videos-book13/page-109.mp4 https://www.youtube.com/embed/IuiqLCE_C2I 115 2026-10-03T13:03:37+00:00 yes https://xdme.com/watch-book13-q110.html https://xdme.com/book13-thumbs/page-110.jpg Why Can One Tiny LED Shine Red, Green, or Blue? An LED is a tiny chip that glows when electricity flows through it! The chemicals inside the chip decide the color of the glow. So one kind of chip glows red, another green, and an https://socialmedia.xdme.com/tony/videos-book13/page-110.mp4 https://www.youtube.com/embed/hrPKuMnsfWc 112 2026-10-03T13:06:39+00:00 yes https://xdme.com/watch-book13-q111.html https://xdme.com/book13-thumbs/page-111.jpg Why Does a Flashlight Beam Get Wider the Farther It Goes? A flashlight beam gets wider the farther it goes because light spreads out! The same light covers a bigger and bigger circle. So the beam gets weaker too. https://socialmedia.xdme.com/tony/videos-book13/page-111.mp4 https://www.youtube.com/embed/YMbxiwrELPQ 111 2026-10-03T13:09:11+00:00 yes https://xdme.com/watch-book13-q112.html https://xdme.com/book13-thumbs/page-112.jpg Why Does a Flashlight Have a Shiny Cup Behind the Bulb? A flashlight has a shiny cup behind the bulb to catch light that goes backward! The curved cup bounces it forward. So the beam is brighter and stronger. https://socialmedia.xdme.com/tony/videos-book13/page-112.mp4 https://www.youtube.com/embed/EbVMmmHq1vI 113 2026-10-03T13:12:15+00:00 yes https://xdme.com/watch-book13-q113.html https://xdme.com/book13-thumbs/page-113.jpg Why Does a Mirror Ball Scatter Dots of Light Around a Room? A mirror ball is covered in lots of tiny flat mirrors, all tilted a little differently! Each mirror sends a small spot of light somewhere else. Together, they scatter dots around t https://socialmedia.xdme.com/tony/videos-book13/page-113.mp4 https://www.youtube.com/embed/7yhzjaPX7Hc 113 2026-10-03T13:15:19+00:00 yes https://xdme.com/watch-book13-q114.html https://xdme.com/book13-thumbs/page-114.jpg Why Do 3-D Glasses Make Pictures Seem to Pop Out? 3-D glasses make pictures pop out because your two eyes see slightly different views! The glasses make sure each eye sees only its own picture. Your brain does the rest. https://socialmedia.xdme.com/tony/videos-book13/page-114.mp4 https://www.youtube.com/embed/_2zylsGw32U 111 2026-10-03T13:17:51+00:00 yes https://xdme.com/watch-book13-q115.html https://xdme.com/book13-thumbs/page-115.jpg Why Do Some Screens Go Dark When You Tilt Polarized Glasses? Polarized lenses only let through light that wiggles in one direction! Many screens already give off light that wiggles one way. If the glasses block that direction, the screen loo https://socialmedia.xdme.com/tony/videos-book13/page-115.mp4 https://www.youtube.com/embed/NoKYl1BhmLU 123 2026-10-03T13:20:54+00:00 yes https://xdme.com/watch-book13-q116.html https://xdme.com/book13-thumbs/page-116.jpg Why Do Magicians' Mirror Tricks Fool Our Eyes? Magicians' mirror tricks fool our eyes because we expect reflections to show what is straight behind the mirror! A slanted mirror can show a side wall instead. Then the audience se https://socialmedia.xdme.com/tony/videos-book13/page-116.mp4 https://www.youtube.com/embed/XFrTwmWNAIw 111 2026-10-03T13:23:56+00:00 yes https://xdme.com/watch-book13-q117.html https://xdme.com/book13-thumbs/page-117.jpg Why Does the Same Line Look Longer with Arrowheads on the Ends? Two lines of the same length can look different if you put arrowheads on the ends! This is the Müller-Lyer illusion. It happens because seeing is a job your brain does, not just yo https://socialmedia.xdme.com/tony/videos-book13/page-117.mp4 https://www.youtube.com/embed/IPM6MwbHeaw 113 2026-10-03T13:26:30+00:00 yes https://xdme.com/watch-book13-q118.html https://xdme.com/book13-thumbs/page-118.jpg Why Can a Laser Measure How Far Away a Wall Is? A laser measuring tool finds a distance by timing a flash of light! The flash bounces off the wall and comes back, and a clock inside measures how long the trip took. Never point a https://socialmedia.xdme.com/tony/videos-book13/page-118.mp4 https://www.youtube.com/embed/2aDb7oLI6J8 107 2026-10-03T13:29:32+00:00 yes https://xdme.com/watch-book13-q119.html https://xdme.com/book13-thumbs/page-119.jpg Why Can a Scanner Copy a Picture Using a Moving Line of Light? A scanner copies a picture by sliding a bright bar of light across it! Tiny sensors measure how much light bounces back from each spot. The scanner builds the picture line by line. https://socialmedia.xdme.com/tony/videos-book13/page-119.mp4 https://www.youtube.com/embed/MMwTk7LgT1g 108 2026-10-03T13:32:35+00:00 yes https://xdme.com/watch-book13-q120.html https://xdme.com/book13-thumbs/page-120.jpg Why Do Indoor Plant Lamps Often Look Pink or Purple? Indoor plant lamps often look pink or purple because they use red and blue light! Plants use those colors the most. Mixing red and blue makes the glow look pink or purple. https://socialmedia.xdme.com/tony/videos-book13/page-120.mp4 https://www.youtube.com/embed/PFdOK3SUSyg 109 2026-10-03T13:35:07+00:00 yes https://xdme.com/watch-book13-q121.html https://xdme.com/book13-thumbs/page-121.jpg Why Do Some Solar Power Plants Use Hundreds of Mirrors? Some solar power plants use hundreds of mirrors to gather sunlight! The mirrors tilt to follow the Sun and aim at one spot on a tower. That spot gets extremely hot and helps make e https://socialmedia.xdme.com/tony/videos-book13/page-121.mp4 https://www.youtube.com/embed/vQgS2B8VrIk 111 2026-10-03T13:38:09+00:00 yes https://xdme.com/watch-book13-q122.html https://xdme.com/book13-thumbs/page-122.jpg Why Does a Lamp Look Dimmer the Farther Away It Is? A lamp looks dimmer the farther away it is because its light spreads out! Farther away, the light is thinner. Your eyes catch less of it. https://socialmedia.xdme.com/tony/videos-book13/page-122.mp4 https://www.youtube.com/embed/h2byofQ5cV0 106 2026-10-03T13:41:24+00:00 yes https://xdme.com/watch-book13-q123.html https://xdme.com/book13-thumbs/page-123.jpg Why Can a Laser Read the Tiny Bumps on a Disc? A disc has a long track of tiny pits and flat spots, and a laser inside the player reads it. A sensor notices how the laser light bounces back, and those patterns turn into sound o https://socialmedia.xdme.com/tony/videos-book13/page-123.mp4 https://www.youtube.com/embed/uCBVaEDZVAM 109 2026-10-03T13:43:58+00:00 yes https://xdme.com/watch-book13-q124.html https://xdme.com/book13-thumbs/page-124.jpg Why Do Neon Signs Glow? A neon sign is a glass tube filled with a little neon gas! High-voltage electricity makes the gas glow orange-red. Other gases and coatings make other colors. https://socialmedia.xdme.com/tony/videos-book13/page-124.mp4 https://www.youtube.com/embed/hilY0xfFBP0 113 2026-10-03T13:46:31+00:00 yes https://xdme.com/watch-book13-q125.html https://xdme.com/book13-thumbs/page-125.jpg How Can a Small Mirror Flash a Signal Across a Valley? A small mirror can flash a signal across a valley because it can send light a long way! Tilt the mirror, and the bright spot jumps around. Hikers have used this to signal for help. https://socialmedia.xdme.com/tony/videos-book13/page-125.mp4 https://www.youtube.com/embed/-X1LKyE7o4Q 110 2026-10-03T13:49:49+00:00 yes https://xdme.com/watch-book13-q126.html https://xdme.com/book13-thumbs/page-126.jpg Why Do Bike Reflectors Shine When a Car's Headlights Hit Them? A bike reflector shines because it sends headlight beams straight back to the driver! It is covered in tiny three-sided mirror corners. That makes you easy to spot in the dark. https://socialmedia.xdme.com/tony/videos-book13/page-126.mp4 https://www.youtube.com/embed/LRm6ujSfr4g 110 2026-10-03T13:52:22+00:00 yes https://xdme.com/watch-book13-q127.html https://xdme.com/book13-thumbs/page-127.jpg Why Do Crossing Guards and Road Workers Wear Bright Vests? Crossing guards and road workers wear bright vests so drivers can see them early! The vests are bright yellow-green or orange, and they have reflective strips. Together, they work https://socialmedia.xdme.com/tony/videos-book13/page-127.mp4 https://www.youtube.com/embed/-EKTbLsES0w 114 2026-10-03T13:55:24+00:00 yes https://xdme.com/watch-book13-q128.html https://xdme.com/book13-thumbs/page-128.jpg Why Do Bikes Need a White Light in Front and a Red Light in Back? Bikes need a white light in front and a red light in back so others know where you are going! White looks like a car's headlight. Red means stop or danger. https://socialmedia.xdme.com/tony/videos-book13/page-128.mp4 https://www.youtube.com/embed/snNz9hXkHEw 104 2026-10-03T13:57:58+00:00 yes https://xdme.com/watch-book13-q129.html https://xdme.com/book13-thumbs/page-129.jpg Why Does a Flashlight Look Weaker in Fog or Rain? A flashlight looks weaker in fog or rain because tiny water drops scatter the light! Each drop bounces some light in every direction. Less light gets through to faraway things. https://socialmedia.xdme.com/tony/videos-book13/page-129.mp4 https://www.youtube.com/embed/_S3uiDfG89o 106 2026-10-03T14:00:30+00:00 yes https://xdme.com/watch-book13-q130.html https://xdme.com/book13-thumbs/page-130.jpg Why Do Some Lamps Look Warm and Yellow While Others Look Cool and White? Some lamps look warm and yellow, and others look cool and white, because they give off different mixes of colors! Warm lamps have more orange and yellow. Cool lamps have more blue. https://socialmedia.xdme.com/tony/videos-book13/page-130.mp4 https://www.youtube.com/embed/ePVuGu58lJM 111 2026-10-03T14:03:03+00:00 yes https://xdme.com/watch-book13-q131.html https://xdme.com/book13-thumbs/page-131.jpg Why Does a Flashlight Get Dimmer as Its Batteries Run Down? A flashlight gets dimmer as its batteries run down because the battery is running out of energy! A fresh battery gives a strong push of electricity. A tired battery gives only a we https://socialmedia.xdme.com/tony/videos-book13/page-131.mp4 https://www.youtube.com/embed/vOsHIW71OE0 111 2026-10-03T14:05:36+00:00 yes https://xdme.com/watch-book13-q132.html https://xdme.com/book13-thumbs/page-132.jpg Why Is It Easier to Read When a Lamp Shines on the Page? It is easier to read when a lamp shines on the page because the page gets plenty of light! Your eyes work best when the words are bright and clear. A lamp placed to the side, witho https://socialmedia.xdme.com/tony/videos-book13/page-132.mp4 https://www.youtube.com/embed/4NAa6fe9538 109 2026-10-03T14:08:48+00:00 yes https://xdme.com/watch-book13-q133.html https://xdme.com/book13-thumbs/page-133.jpg Why Should You Never Look Straight Into Very Bright Lights? Never look straight into very bright lights, because they can hurt your eyes! Your eyes handle ordinary daylight well, but they have limits. Never look straight at the Sun, and ask https://socialmedia.xdme.com/tony/videos-book13/page-133.mp4 https://www.youtube.com/embed/UTSnd9LWgIQ 109 2026-10-03T14:10:51+00:00 yes https://xdme.com/watch-book13-q134.html https://xdme.com/book13-thumbs/page-134.jpg Why Do Night-Lights Stay Dim on Purpose? Night-lights stay dim on purpose because a little light is all you need! A dim glow lets you see shapes and find the door. It also keeps the room restful. https://socialmedia.xdme.com/tony/videos-book13/page-134.mp4 https://www.youtube.com/embed/xC2tG81Vogs 108 2026-10-03T14:13:54+00:00 yes https://xdme.com/watch-book13-q135.html https://xdme.com/book13-thumbs/page-135.jpg Why Do Exit Signs Stay Lit Even When the Power Goes Out? Exit signs stay lit even when the power goes out, so they can always show the way! They have a small battery inside, and some glow with special paint. That helps everyone get out s https://socialmedia.xdme.com/tony/videos-book13/page-135.mp4 https://www.youtube.com/embed/JsOOh8mssw4 108 2026-10-03T14:16:26+00:00 yes https://xdme.com/watch-book13-q136.html https://xdme.com/book13-thumbs/page-136.jpg Why Do Drivers Switch Off Their High Beams for Oncoming Cars? Drivers switch off their high beams for oncoming cars because bright light dazzles other drivers! High beams shine far down dark roads. But they make it hard for others to see. https://socialmedia.xdme.com/tony/videos-book13/page-136.mp4 https://www.youtube.com/embed/2FAHYak05aM 108 2026-10-03T14:18:59+00:00 yes https://xdme.com/watch-book13-q137.html https://xdme.com/book13-thumbs/page-137.jpg Why Do Airplanes and Boats Have Red and Green Lights? Planes and boats have a red light on the left side and a green light on the right side! In the dark, the colors tell you which way the vehicle is going. They also have a white ligh https://socialmedia.xdme.com/tony/videos-book13/page-137.mp4 https://www.youtube.com/embed/dxMeRufldAQ 105 2026-10-03T14:22:01+00:00 yes https://xdme.com/watch-book13-q138.html https://xdme.com/book13-thumbs/page-138.jpg Why Do Tall Towers Have Blinking Red Lights? Tall towers blink red at night so airplane pilots can see them from far away! Red is easy to see against the dark sky, and it stands out from the stars. Flashing grabs attention to https://socialmedia.xdme.com/tony/videos-book13/page-138.mp4 https://www.youtube.com/embed/F7zgbI4mIIM 112 2026-10-03T14:25:05+00:00 yes https://xdme.com/watch-book13-q139.html https://xdme.com/book13-thumbs/page-139.jpg Why Are Tunnels Extra Bright Near the Entrance? Tunnels are extra bright near the entrance so your eyes can adjust! Going from bright sunshine into a dim tunnel feels like going into darkness. Extra lights make that change small https://socialmedia.xdme.com/tony/videos-book13/page-139.mp4 https://www.youtube.com/embed/09Rx4vAEkcQ 110 2026-10-03T14:27:36+00:00 yes https://xdme.com/watch-book13-q140.html https://xdme.com/book13-thumbs/page-140.jpg Why Do Window Blinds Control How Much Light Comes In? Window blinds control light with slats that can tilt up, down, or close! Tilting the slats changes where the light goes and how much comes in. That lets you make a room brighter or https://socialmedia.xdme.com/tony/videos-book13/page-140.mp4 https://www.youtube.com/embed/EFjXS5zR1mQ 109 2026-10-03T14:31:12+00:00 yes https://xdme.com/watch-book13-q141.html https://xdme.com/book13-thumbs/page-141.jpg Why Do Lamps Have Shades? Lamps have shades because a bare bulb is very bright and glares in your eyes! A shade covers the bulb and softens the light. It can also steer the light where you want it. https://socialmedia.xdme.com/tony/videos-book13/page-141.mp4 https://www.youtube.com/embed/xi8M6D9x2E4 104 2026-10-03T14:33:44+00:00 yes https://xdme.com/watch-book13-q142.html https://xdme.com/book13-thumbs/page-142.jpg What Is Ultraviolet Light, and Why Can't We See It? Ultraviolet light, or UV, has waves a little shorter than violet light, so our eyes cannot see it! The Sun gives off a lot of UV, and it can cause sunburn and hurt your eyes. Never https://socialmedia.xdme.com/tony/videos-book13/page-142.mp4 https://www.youtube.com/embed/iB5KrdAno8k 111 2026-10-03T14:36:53+00:00 yes https://xdme.com/watch-book13-q143.html https://xdme.com/book13-thumbs/page-143.jpg Why Are Special Eclipse Glasses Safe When Ordinary Sunglasses Are Not? Special eclipse glasses are safe because they block almost all of the Sun's light! Ordinary sunglasses, even very dark ones, let in far too much. Never look straight at the Sun, an https://socialmedia.xdme.com/tony/videos-book13/page-143.mp4 https://www.youtube.com/embed/DMJ5qsAA1kY 121 2026-10-03T14:39:56+00:00 yes https://xdme.com/watch-book13-q144.html https://xdme.com/book13-thumbs/page-144.jpg Why Are Old Paintings and Photographs Kept in Dim Light? Old paintings and photographs are kept in dim light because light can slowly fade them! Light carries energy. Over many years, that energy can break apart colors. https://socialmedia.xdme.com/tony/videos-book13/page-144.mp4 https://www.youtube.com/embed/EFfeJSOzDEU 113 2026-10-03T14:43:36+00:00 yes https://xdme.com/watch-book13-q145.html https://xdme.com/book13-thumbs/page-145.jpg Why Are Brake Lights Red? Brake lights are red because red light can be seen from far away! Red is not scattered as much by fog, dust, and rain. And people quickly learn that red means stop. https://socialmedia.xdme.com/tony/videos-book13/page-145.mp4 https://www.youtube.com/embed/G7W73_1O_UM 108 2026-10-03T14:46:10+00:00 yes https://xdme.com/watch-book13-q146.html https://xdme.com/book13-thumbs/page-146.jpg Why Do Emergency Vehicles Flash Red and Blue Lights? Emergency vehicles flash red and blue lights because those lights are made to stand out! They are bright, they change quickly, and they use two very different colors. That catches https://socialmedia.xdme.com/tony/videos-book13/page-146.mp4 https://www.youtube.com/embed/6gY8JVyN3yo 107 2026-10-03T14:49:14+00:00 yes https://xdme.com/watch-book13-q147.html https://xdme.com/book13-thumbs/page-147.jpg Why Should You Keep Paper and Curtains Away From Hot Lamps? Keep paper and curtains away from hot lamps, because some lamps get hot enough to scorch them! Heat can even start a fire if something stays too close for too long. Safe science is https://socialmedia.xdme.com/tony/videos-book13/page-147.mp4 https://www.youtube.com/embed/ypcj6lUFJBg 109 2026-10-03T14:52:17+00:00 yes https://xdme.com/watch-book13-q148.html https://xdme.com/book13-thumbs/page-148.jpg Why Can You See a Line of Light Under a Closed Door? You can see a line of light under a closed door because light squeezes through the gap! Light travels in straight lines, and it also bounces. The gap is narrow, so you see a thin l https://socialmedia.xdme.com/tony/videos-book13/page-148.mp4 https://www.youtube.com/embed/ky3YcNQWyp8 100 2026-10-03T14:56:15+00:00 yes https://xdme.com/watch-book13-q149.html https://xdme.com/book13-thumbs/page-149.jpg Why Do Some Athletes Put Dark Marks Under Their Eyes? Some athletes put dark marks under their eyes to cut glare! Dark patches absorb light that would bounce off their cheeks into their eyes. That can help a little on sunny days. https://socialmedia.xdme.com/tony/videos-book13/page-149.mp4 https://www.youtube.com/embed/uCpEL5tVVq0 106 2026-10-03T15:02:22+00:00 yes https://xdme.com/watch-book13-q150.html https://xdme.com/book13-thumbs/page-150.jpg What Is Light Really Made Of? Light is a form of energy that travels as waves! It also comes in tiny packets called photons. Light acts like a wave in some ways and like a stream of particles in others. https://socialmedia.xdme.com/tony/videos-book13/page-150.mp4 https://www.youtube.com/embed/ZEd9Whty-gY 108 2026-10-03T15:06:56+00:00 yes https://xdme.com/watch-book14-q001.html https://xdme.com/book14-thumbs/page-001.jpg Why Does Every Sound Begin with Something Shaking? Every sound begins with a vibration, which is something moving back and forth very fast! The shaking thing pushes on the air next to it, and that push spreads out as a wave. When t https://socialmedia.xdme.com/tony/videos-book14/page-001.mp4 https://www.youtube.com/embed/mzJZ2-rc7MA 114 2026-10-03T15:09:10+00:00 yes https://xdme.com/watch-book14-q002.html https://xdme.com/book14-thumbs/page-002.jpg Why Does Your Throat Tickle When You Hum? Your throat tickles because tiny flaps inside it are fluttering super fast! Air from your lungs rushes past them, and they open and shut again and again. That flutter is a vibratio https://socialmedia.xdme.com/tony/videos-book14/page-002.mp4 https://www.youtube.com/embed/sJ9x5q2gqP4 111 2026-10-03T15:09:12+00:00 yes https://xdme.com/watch-book14-q003.html https://xdme.com/book14-thumbs/page-003.jpg Why Does a Ruler Buzz When You Flick It Off the Edge of a Desk? A flicked ruler bends and springs back, over and over, and that makes a buzz! Each wiggle pushes on the air and makes a tiny sound. The wiggles come so fast that your ears hear one https://socialmedia.xdme.com/tony/videos-book14/page-003.mp4 https://www.youtube.com/embed/_pEYne2lsEE 108 2026-10-03T15:09:13+00:00 yes https://xdme.com/watch-book14-q004.html https://xdme.com/book14-thumbs/page-004.jpg What Is a Sound Wave Actually Made Of? A sound wave is made of squeezed and stretched air! Where the air is squeezed, tiny particles bunch together, and where it is stretched, they spread apart. That pattern travels out https://socialmedia.xdme.com/tony/videos-book14/page-004.mp4 https://www.youtube.com/embed/qYYoYGUZaA8 116 2026-10-03T15:12:20+00:00 yes https://xdme.com/watch-book14-q005.html https://xdme.com/book14-thumbs/page-005.jpg Why Does a Slinky Show How a Sound Wave Moves? A slinky is like a long row of air particles joined by springs! Push a few coils together, and the squeeze travels along it just like a sound wave. That makes it a perfect model fo https://socialmedia.xdme.com/tony/videos-book14/page-005.mp4 https://www.youtube.com/embed/GqEG_rzXXPQ 111 2026-10-03T15:15:23+00:00 yes https://xdme.com/watch-book14-q006.html https://xdme.com/book14-thumbs/page-006.jpg How Are Water Ripples Like Sound Waves? Water ripples and sound waves are alike because both carry energy without carrying stuff along! A ripple spreads in circles from where a pebble lands. A sound spreads outward from https://socialmedia.xdme.com/tony/videos-book14/page-006.mp4 https://www.youtube.com/embed/ezLMGtFLyE4 110 2026-10-03T15:18:28+00:00 yes https://xdme.com/watch-book14-q007.html https://xdme.com/book14-thumbs/page-007.jpg Why Does Rice Dance on Plastic Wrap When You Bang a Pot Nearby? Rice dances on plastic wrap because sound waves make the wrap wiggle! The wiggling wrap bumps the rice grains up and down. The dancing grains show you that sound really is moving s https://socialmedia.xdme.com/tony/videos-book14/page-007.mp4 https://www.youtube.com/embed/GLb2kpco-dU 108 2026-10-03T15:21:32+00:00 yes https://xdme.com/watch-book14-q008.html https://xdme.com/book14-thumbs/page-008.jpg Why Does a Tuning Fork Keep Ringing for a While? A tuning fork rings for a long time because its metal loses energy very slowly! After you tap it, the two prongs spring back and forth at the same steady rate. That makes a pure, s https://socialmedia.xdme.com/tony/videos-book14/page-008.mp4 https://www.youtube.com/embed/89NC7m8xauE 111 2026-10-03T15:24:35+00:00 yes https://xdme.com/watch-book14-q009.html https://xdme.com/book14-thumbs/page-009.jpg Why Can You Feel Deep Bass Thumping in Your Chest? You feel deep bass in your chest because low sounds are big, slow shakes! Those shakes are strong enough to make your skin and chest vibrate. So your body feels the sound while you https://socialmedia.xdme.com/tony/videos-book14/page-009.mp4 https://www.youtube.com/embed/4ge2pXGhXaE 106 2026-10-03T15:27:19+00:00 yes https://xdme.com/watch-book14-q010.html https://xdme.com/book14-thumbs/page-010.jpg Why Does Pushing a Swing at Just the Right Moment Work So Well? Pushing a swing at just the right moment works because a swing has its own natural rhythm! Push in time with that rhythm, and every push adds a little more motion. This is called r https://socialmedia.xdme.com/tony/videos-book14/page-010.mp4 https://www.youtube.com/embed/FQjzRkGvKfU 109 2026-10-03T15:30:21+00:00 yes https://xdme.com/watch-book14-q011.html https://xdme.com/book14-thumbs/page-011.jpg Why Does a Tuning Fork Sound Louder When You Touch It to a Table? A tuning fork sounds louder on a table because the whole tabletop shakes with it! A fork alone pushes only a tiny bit of air. A big flat surface pushes much more air, so you hear a https://socialmedia.xdme.com/tony/videos-book14/page-011.mp4 https://www.youtube.com/embed/Cw2Zcj50_TQ 108 2026-10-03T15:33:24+00:00 yes https://xdme.com/watch-book14-q012.html https://xdme.com/book14-thumbs/page-012.jpg Why Can a Tin-Can Phone Carry a Voice? A tin-can phone carries a voice because the string carries the shaking! Your voice makes the bottom of the cup vibrate. The vibration runs along the string and shakes the other cup https://socialmedia.xdme.com/tony/videos-book14/page-012.mp4 https://www.youtube.com/embed/9ekLsNwkGtQ 108 2026-10-03T15:36:27+00:00 yes https://xdme.com/watch-book14-q013.html https://xdme.com/book14-thumbs/page-013.jpg What Does It Mean When We Say a Sound Has a Frequency? Frequency tells you how many times something vibrates in one second! We measure it in a unit called hertz. More vibrations each second means a higher sound. https://socialmedia.xdme.com/tony/videos-book14/page-013.mp4 https://www.youtube.com/embed/QIQiQiPKbco 121 2026-10-03T15:39:30+00:00 yes https://xdme.com/watch-book14-q014.html https://xdme.com/book14-thumbs/page-014.jpg Why Do Puddles Shiver When a Heavy Truck Rumbles By? Puddles shiver when a heavy truck rumbles by because the truck shakes the ground! The shaking spreads through the ground as waves. When the waves reach a puddle, its surface wobble https://socialmedia.xdme.com/tony/videos-book14/page-014.mp4 https://www.youtube.com/embed/Cc05DXhgOcg 109 2026-10-03T15:42:56+00:00 yes https://xdme.com/watch-book14-q015.html https://xdme.com/book14-thumbs/page-015.jpg Why Do Wood, Metal, and Glass Sound Different When You Tap Them? Wood, metal, and glass sound different because they vibrate in different ways! Stiff, springy materials ring, and soft, squishy ones go thud. The sound tells you something about wh https://socialmedia.xdme.com/tony/videos-book14/page-015.mp4 https://www.youtube.com/embed/IdVyRqUzb6E 113 2026-10-03T15:45:59+00:00 yes https://xdme.com/watch-book14-q016.html https://xdme.com/book14-thumbs/page-016.jpg Why Does a Bottle Hum When You Blow Across the Top? A bottle hums when you blow across the top because the air inside starts to vibrate! Your breath makes the air in the bottle bounce back and forth. That steady bounce is the hum yo https://socialmedia.xdme.com/tony/videos-book14/page-016.mp4 https://www.youtube.com/embed/N1c2pPf9Z1o 108 2026-10-03T15:49:32+00:00 yes https://xdme.com/watch-book14-q017.html https://xdme.com/book14-thumbs/page-017.jpg Why Does a Fan Hum Higher When It Speeds Up? A fan hums higher when it speeds up because its blades push the air more often! Each blade gives the air a little push as it passes. More pushes each second means a higher hum. https://socialmedia.xdme.com/tony/videos-book14/page-017.mp4 https://www.youtube.com/embed/jtGl1W4RrBU 108 2026-10-03T15:52:45+00:00 yes https://xdme.com/watch-book14-q018.html https://xdme.com/book14-thumbs/page-018.jpg Why Does a Card in Bicycle Spokes Make a Buzzing Motor Sound? A card in bicycle spokes sounds like a motor because it clicks very quickly! Each spoke flicks the card once as the wheel turns. When the wheel is fast, the clicks blend into a buz https://socialmedia.xdme.com/tony/videos-book14/page-018.mp4 https://www.youtube.com/embed/b_3EbHxeK3k 110 2026-10-03T15:55:48+00:00 yes https://xdme.com/watch-book14-q019.html https://xdme.com/book14-thumbs/page-019.jpg Why Do Refrigerators Hum? Refrigerators hum because a motor inside them shakes! The shaking spreads into the fridge's walls, and the walls push on the air. Because the shaking repeats the same way again and https://socialmedia.xdme.com/tony/videos-book14/page-019.mp4 https://www.youtube.com/embed/O3O283x4MFo 113 2026-10-03T15:58:51+00:00 yes https://xdme.com/watch-book14-q020.html https://xdme.com/book14-thumbs/page-020.jpg Why Can You Hear a Mosquito's Wings but Not a Slowly Flapping Bird's? You hear a mosquito's wings because they beat hundreds of times each second! That is fast enough to make a tone your ears can hear. A bird's wings flap far too slowly to make a ton https://socialmedia.xdme.com/tony/videos-book14/page-020.mp4 https://www.youtube.com/embed/-2mmo8biSAk 112 2026-10-03T16:02:10+00:00 yes https://xdme.com/watch-book14-q021.html https://xdme.com/book14-thumbs/page-021.jpg Why Do Sound Waves Push and Squeeze Instead of Going Up and Down? Sound waves push and squeeze the air in the same direction the wave travels! That is different from water waves or a shaken rope. Scientists call sound a longitudinal wave. https://socialmedia.xdme.com/tony/videos-book14/page-021.mp4 https://www.youtube.com/embed/Rs04YVDPjnE 113 2026-10-03T16:04:41+00:00 yes https://xdme.com/watch-book14-q022.html https://xdme.com/book14-thumbs/page-022.jpg Why Does a Stadium Wave Move Across the Crowd While the People Stay Put? In a stadium wave, the wave travels while the people stay in their seats! Each person stands up and sits down in turn. That shows that a wave moves energy, not the things it passes https://socialmedia.xdme.com/tony/videos-book14/page-022.mp4 https://www.youtube.com/embed/P7q-RLBABe0 113 2026-10-03T16:08:15+00:00 yes https://xdme.com/watch-book14-q023.html https://xdme.com/book14-thumbs/page-023.jpg Why Do Two Nearly Matching Sounds Make a Wobbling Wah-Wah? Two nearly matching sounds make a wobbling wah-wah because their waves keep lining up and canceling! You hear loud, then quiet, then loud again. That wobble is called a beat. https://socialmedia.xdme.com/tony/videos-book14/page-023.mp4 https://www.youtube.com/embed/CFnRbjBAhZc 111 2026-10-03T16:11:28+00:00 yes https://xdme.com/watch-book14-q024.html https://xdme.com/book14-thumbs/page-024.jpg Why Can't We See Sound Waves? We cannot see sound waves because they are tiny changes in air pressure, and our eyes cannot see air! But we can see what sound does. Special tools can even draw sound waves for us https://socialmedia.xdme.com/tony/videos-book14/page-024.mp4 https://www.youtube.com/embed/uvcvgFXnjEI 110 2026-10-03T16:14:33+00:00 yes https://xdme.com/watch-book14-q025.html https://xdme.com/book14-thumbs/page-025.jpg Why Does a Fast-Shaking Object Look Blurry? A fast-shaking object looks blurry because your eyes cannot follow motion that quick! Each wiggle takes only a fraction of a second. Your eyes mix all the positions together into a https://socialmedia.xdme.com/tony/videos-book14/page-025.mp4 https://www.youtube.com/embed/S-4htQtz0g0 108 2026-10-03T16:17:16+00:00 yes https://xdme.com/watch-book14-q026.html https://xdme.com/book14-thumbs/page-026.jpg Why Are Big Things Usually Lower in Sound than Small Things? Big things are usually lower in sound because they swing back and forth more slowly! Slow vibrations make low sounds. Small, light things vibrate quickly, so they make high sounds. https://socialmedia.xdme.com/tony/videos-book14/page-026.mp4 https://www.youtube.com/embed/WH_wcVAR68I 113 2026-10-03T16:20:50+00:00 yes https://xdme.com/watch-book14-q027.html https://xdme.com/book14-thumbs/page-027.jpg What Makes One Sound Louder than Another? A sound is louder when the vibration is bigger! A larger back-and-forth swing pushes the air harder and carries more energy to your ears. A tiny wiggle carries only a little energy https://socialmedia.xdme.com/tony/videos-book14/page-027.mp4 https://www.youtube.com/embed/BRlhB4GwBI0 113 2026-10-03T16:24:24+00:00 yes https://xdme.com/watch-book14-q028.html https://xdme.com/book14-thumbs/page-028.jpg What Makes a Sound High or Low? A sound is high or low because of its frequency, which is how fast it vibrates! A fast vibration makes a high pitch. A slow vibration makes a low pitch. https://socialmedia.xdme.com/tony/videos-book14/page-028.mp4 https://www.youtube.com/embed/zNdQW689pN0 110 2026-10-03T16:27:26+00:00 yes https://xdme.com/watch-book14-q029.html https://xdme.com/book14-thumbs/page-029.jpg Why Do Mosquitoes Whine High While Bumblebees Buzz Low? Mosquitoes whine high and bumblebees buzz low because of how fast their wings flap! A mosquito flaps hundreds of times each second. A bumblebee flaps more slowly, so its buzz is lo https://socialmedia.xdme.com/tony/videos-book14/page-029.mp4 https://www.youtube.com/embed/MVdpDGQ0xcQ 115 2026-10-03T16:30:02+00:00 yes https://xdme.com/watch-book14-q030.html https://xdme.com/book14-thumbs/page-030.jpg Why Does a Ruler Twang Lower When More of It Hangs Over the Edge? A ruler twangs lower when more of it hangs over the edge because the longer free end swings more slowly! Slower wiggles make lower sounds. Slide the ruler in, and the wiggles speed https://socialmedia.xdme.com/tony/videos-book14/page-030.mp4 https://www.youtube.com/embed/Wzy2xNa0E2g 111 2026-10-03T16:32:35+00:00 yes https://xdme.com/watch-book14-q031.html https://xdme.com/book14-thumbs/page-031.jpg Why Does the Sound of Pouring Water Get Higher as the Glass Fills? Pouring water gets higher in pitch as the glass fills because the air above the water gets shorter! Air in a shorter space vibrates faster, and faster vibrations sound higher. So y https://socialmedia.xdme.com/tony/videos-book14/page-031.mp4 https://www.youtube.com/embed/il-4BMvvNPw 112 2026-10-03T16:38:48+00:00 yes https://xdme.com/watch-book14-q032.html https://xdme.com/book14-thumbs/page-032.jpg What Do Decibels Measure? Decibels measure how strong a sound is! We write the unit as dB. The bigger the number, the more powerful the sound, so a high dB number means a loud sound. https://socialmedia.xdme.com/tony/videos-book14/page-032.mp4 https://www.youtube.com/embed/_ff1HccRe9k 117 2026-10-03T16:42:19+00:00 yes https://xdme.com/watch-book14-q033.html https://xdme.com/book14-thumbs/page-033.jpg Why Do 10 More Decibels Sound About Twice as Loud? Ten more decibels sound about twice as loud because our ears work on a special scale! Each 10 decibels means about ten times more sound energy. But our ears only judge it as roughl https://socialmedia.xdme.com/tony/videos-book14/page-033.mp4 https://www.youtube.com/embed/6llk4VLuuXw 115 2026-10-03T16:45:22+00:00 yes https://xdme.com/watch-book14-q034.html https://xdme.com/book14-thumbs/page-034.jpg Why Does Cupping Your Hands Behind Your Ears Help You Hear? Cupping your hands behind your ears helps you hear because it makes your ear funnel bigger! More sound waves get gathered and aimed into your ear canal. It can boost the sound a li https://socialmedia.xdme.com/tony/videos-book14/page-034.mp4 https://www.youtube.com/embed/BrfaJy5Pbz4 108 2026-10-03T16:48:26+00:00 yes https://xdme.com/watch-book14-q035.html https://xdme.com/book14-thumbs/page-035.jpg Why Does Fresh Snow Make Everything Sound So Quiet? Fresh snow makes everything sound quiet because it soaks up sound! It is full of tiny air pockets between the flakes. Sound waves get lost in those pockets instead of bouncing back https://socialmedia.xdme.com/tony/videos-book14/page-035.mp4 https://www.youtube.com/embed/E0EBgjmA_vg 113 2026-10-03T16:51:29+00:00 yes https://xdme.com/watch-book14-q036.html https://xdme.com/book14-thumbs/page-036.jpg Why Do Carpets and Curtains Make a Room Sound Quieter? Carpets and curtains make a room quieter because they soak up sound! Their soft, fuzzy fibers trap sound waves. Hard walls and floors bounce sound back, but soft things absorb it. https://socialmedia.xdme.com/tony/videos-book14/page-036.mp4 https://www.youtube.com/embed/A4BM0EetaVc 114 2026-10-03T16:54:34+00:00 yes https://xdme.com/watch-book14-q037.html https://xdme.com/book14-thumbs/page-037.jpg Why Do Deep Rumbles Carry Farther than Squeaks? Deep rumbles carry farther than squeaks because low sounds have long waves! Long waves spread widely and bend around things. High sounds fade out more quickly in air and get blocke https://socialmedia.xdme.com/tony/videos-book14/page-037.mp4 https://www.youtube.com/embed/CawANgif2rg 113 2026-10-03T16:57:36+00:00 yes https://xdme.com/watch-book14-q038.html https://xdme.com/book14-thumbs/page-038.jpg Why Can't We Hear a Dog Whistle? We cannot hear a dog whistle because it makes sounds above 20,000 hertz! That is higher than humans can hear. Dogs hear much higher pitches, so they notice it easily. https://socialmedia.xdme.com/tony/videos-book14/page-038.mp4 https://www.youtube.com/embed/E5-6SLJoAkg 112 2026-10-03T17:00:38+00:00 yes https://xdme.com/watch-book14-q039.html https://xdme.com/book14-thumbs/page-039.jpg Why Would the Quietest Room in the World Feel Strange? The quietest room in the world would feel strange because we are used to hearing some sound all the time! In a super-quiet room, you start to hear things inside your own body. It c https://socialmedia.xdme.com/tony/videos-book14/page-039.mp4 https://www.youtube.com/embed/WHdSY8Fwjgg 108 2026-10-03T17:04:01+00:00 yes https://xdme.com/watch-book14-q040.html https://xdme.com/book14-thumbs/page-040.jpg Why Is It Hard to Hear a Friend in a Noisy Room? It is hard to hear a friend in a noisy room because their voice mixes with all the other sounds! Your ears and brain must pick out one voice from the rest. Noise can mask the quiet https://socialmedia.xdme.com/tony/videos-book14/page-040.mp4 https://www.youtube.com/embed/MtsbCvfVVG4 106 2026-10-03T17:06:41+00:00 yes https://xdme.com/watch-book14-q041.html https://xdme.com/book14-thumbs/page-041.jpg Why Do People Talk Louder When It Is Noisy? People talk louder in noisy places because their brains turn up their voices without them noticing! When it is noisy, you hear your own voice less. This is called the Lombard effec https://socialmedia.xdme.com/tony/videos-book14/page-041.mp4 https://www.youtube.com/embed/-XTVK4uD1JE 109 2026-10-03T17:09:44+00:00 yes https://xdme.com/watch-book14-q042.html https://xdme.com/book14-thumbs/page-042.jpg How Can Two Sounds Cancel Each Other Out? Two sounds can cancel each other out when their waves are exact opposites! Where one wave goes up, the other goes down. When they meet, they add up to almost nothing. https://socialmedia.xdme.com/tony/videos-book14/page-042.mp4 https://www.youtube.com/embed/8-jfhJ8afd0 108 2026-10-03T17:12:47+00:00 yes https://xdme.com/watch-book14-q043.html https://xdme.com/book14-thumbs/page-043.jpg Why Do Foghorns Make Deep Sounds? Foghorns make deep sounds because low sounds travel farther! Low sounds also bend around obstacles. That helps sailors hear where the coast is, even when they cannot see. https://socialmedia.xdme.com/tony/videos-book14/page-043.mp4 https://www.youtube.com/embed/z3Hn5hgxaZ8 108 2026-10-03T17:15:50+00:00 yes https://xdme.com/watch-book14-q044.html https://xdme.com/book14-thumbs/page-044.jpg Why Do Longer Wind-Chime Tubes Ring Lower? Longer wind-chime tubes ring lower because each wiggle takes more time! A longer tube vibrates more slowly. A shorter tube wiggles faster and rings higher. https://socialmedia.xdme.com/tony/videos-book14/page-044.mp4 https://www.youtube.com/embed/_LnAS1FGlv0 108 2026-10-03T17:18:53+00:00 yes https://xdme.com/watch-book14-q045.html https://xdme.com/book14-thumbs/page-045.jpg Why Can You Hear the Ocean in a Seashell? The ocean sound in a seashell is not really the ocean! It is the quiet noise all around you, made louder by the shell's hollow space. A cup or a mug works just as well. https://socialmedia.xdme.com/tony/videos-book14/page-045.mp4 https://www.youtube.com/embed/gziJnZkv-cg 107 2026-10-03T17:22:10+00:00 yes https://xdme.com/watch-book14-q046.html https://xdme.com/book14-thumbs/page-046.jpg Why Does a Sound Seem Softer When You Are Farther Away? A sound seems softer when you are farther away because it spreads out! Sound spreads in all directions like a growing ball. The same energy gets shared over a bigger and bigger spa https://socialmedia.xdme.com/tony/videos-book14/page-046.mp4 https://www.youtube.com/embed/hja4btat7jo 107 2026-10-03T17:24:44+00:00 yes https://xdme.com/watch-book14-q047.html https://xdme.com/book14-thumbs/page-047.jpg Why Do You Hold Your Breath When You Try to Hear a Tiny Sound? You hold your breath to hear a tiny sound because you stop making noise yourself! Your breathing and rustling clothes can cover up very quiet sounds. With less noise, tiny sounds s https://socialmedia.xdme.com/tony/videos-book14/page-047.mp4 https://www.youtube.com/embed/lv99MLwe4ug 106 2026-10-03T17:27:48+00:00 yes https://xdme.com/watch-book14-q048.html https://xdme.com/book14-thumbs/page-048.jpg Why Do Phone Calls Make Voices Sound Thinner? Phone calls make voices sound thinner because a phone sends only part of your voice! It sends roughly the sounds between 300 and 3,400 hertz. It leaves out the deepest and the high https://socialmedia.xdme.com/tony/videos-book14/page-048.mp4 https://www.youtube.com/embed/XWyOgPDO-H4 113 2026-10-03T17:30:53+00:00 yes https://xdme.com/watch-book14-q049.html https://xdme.com/book14-thumbs/page-049.jpg Why Do Sounds Seem Muffled Through a Wall? Sounds seem muffled through a wall because most of the sound bounces back or gets soaked up! The part that gets through makes the wall vibrate a little. The wall then makes a quiet https://socialmedia.xdme.com/tony/videos-book14/page-049.mp4 https://www.youtube.com/embed/dmCNMzojbMg 106 2026-10-03T17:33:55+00:00 yes https://xdme.com/watch-book14-q050.html https://xdme.com/book14-thumbs/page-050.jpg How Can You Hear Someone Talking From Around a Corner? You can hear someone talking from around a corner because sound waves bend and bounce! They spread out around the edges of doors and corners. Light waves are much tinier, so they d https://socialmedia.xdme.com/tony/videos-book14/page-050.mp4 https://www.youtube.com/embed/Ujmb4mMq3es 109 2026-10-03T17:36:32+00:00 yes https://xdme.com/watch-book14-q051.html https://xdme.com/book14-thumbs/page-051.jpg Why Does a Megaphone Make Your Voice Carry Farther? A megaphone is a cone that gathers your voice and points it in one direction! Without a cone, your voice spreads out in every direction and gets thin fast. The cone keeps more of t https://socialmedia.xdme.com/tony/videos-book14/page-051.mp4 https://www.youtube.com/embed/I98nhfa9P3A 119 2026-10-03T17:39:44+00:00 yes https://xdme.com/watch-book14-q052.html https://xdme.com/book14-thumbs/page-052.jpg Why Do Small Speakers Sound Thin and Big Speakers Sound Full? A speaker makes sound by moving a cone in and out to push the air! Deep bass notes need a lot of air pushed slowly. A tiny cone cannot push enough air, so the sound seems thin. https://socialmedia.xdme.com/tony/videos-book14/page-052.mp4 https://www.youtube.com/embed/WrLdYA7hNao 112 2026-10-03T17:42:47+00:00 yes https://xdme.com/watch-book14-q053.html https://xdme.com/book14-thumbs/page-053.jpg Why Does a Microphone Squeal When It Gets Close to a Speaker? A microphone listens and a speaker talks, and sometimes they get stuck in a loop! The mic hears the speaker, and the speaker makes it louder again. Round and round it goes until yo https://socialmedia.xdme.com/tony/videos-book14/page-053.mp4 https://www.youtube.com/embed/F8V2pI3cDpc 109 2026-10-03T17:45:59+00:00 yes https://xdme.com/watch-book14-q054.html https://xdme.com/book14-thumbs/page-054.jpg Why Does a Bell Keep Ringing After You Hit It? A bell keeps ringing because the metal keeps vibrating after you hit it! Stiff metal springs back to its shape again and again. It wastes very little energy, so the ringing lasts a https://socialmedia.xdme.com/tony/videos-book14/page-054.mp4 https://www.youtube.com/embed/wCgGXgrQIuA 107 2026-10-03T17:49:03+00:00 yes https://xdme.com/watch-book14-q055.html https://xdme.com/book14-thumbs/page-055.jpg Why Do Sirens Rise and Fall in Pitch? Many sirens slide up and down in pitch on purpose! A changing sound is easier for our brains to notice than a steady one. That helps people notice the warning quickly, so they can https://socialmedia.xdme.com/tony/videos-book14/page-055.mp4 https://www.youtube.com/embed/Vk_aXXcuubE 109 2026-10-03T17:51:34+00:00 yes https://xdme.com/watch-book14-q056.html https://xdme.com/book14-thumbs/page-056.jpg Why Does a Phone Buzz in Vibrate Mode? A phone buzzes because a tiny part inside shakes the whole phone! The shaking pushes on the air and on whatever the phone is sitting on. That is the buzz you hear, and the shaking https://socialmedia.xdme.com/tony/videos-book14/page-056.mp4 https://www.youtube.com/embed/kYUz-4919tA 107 2026-10-03T17:54:38+00:00 yes https://xdme.com/watch-book14-q057.html https://xdme.com/book14-thumbs/page-057.jpg Why Are Vacuum Cleaners and Hair Dryers So Noisy? Vacuum cleaners and hair dryers are noisy because fast fans push the air hard! The air races through narrow gaps and swirls in messy ways. That swirling air makes hissing and roari https://socialmedia.xdme.com/tony/videos-book14/page-057.mp4 https://www.youtube.com/embed/ON-qBm_PIuM 116 2026-10-03T17:57:42+00:00 yes https://xdme.com/watch-book14-q058.html https://xdme.com/book14-thumbs/page-058.jpg Why Do Some Quiet Electric Cars Hum on Purpose? Some electric cars hum on purpose so that people can hear them coming! At slow speeds, these cars can be almost silent. A gentle hum helps everyone stay safe. https://socialmedia.xdme.com/tony/videos-book14/page-058.mp4 https://www.youtube.com/embed/jPk_PSzA0QY 111 2026-10-03T18:00:45+00:00 yes https://xdme.com/watch-book14-q059.html https://xdme.com/book14-thumbs/page-059.jpg How Can a Needle in a Groove Play a Song? A record has a wavy groove that is a copy of the sound wave! A needle rides in the groove and wiggles from side to side. Those wiggles are tiny vibrations that become music. https://socialmedia.xdme.com/tony/videos-book14/page-059.mp4 https://www.youtube.com/embed/F0rb3weE9kU 111 2026-10-03T18:03:48+00:00 yes https://xdme.com/watch-book14-q060.html https://xdme.com/book14-thumbs/page-060.jpg Why Does Snapping Your Fingers Make a Snap? A finger snap is a fast, tiny slam that makes a crisp sound! Your middle finger slips off your thumb and hits the base of your thumb. That hit makes the snap. https://socialmedia.xdme.com/tony/videos-book14/page-060.mp4 https://www.youtube.com/embed/daG0rnOrLe4 107 2026-10-03T18:06:20+00:00 yes https://xdme.com/watch-book14-q061.html https://xdme.com/book14-thumbs/page-061.jpg Why Does a Clap Make a Sharp Crack? A clap makes a sharp crack because it creates a sudden pulse of air! Your palms squeeze the air between them and push it out in a flash. A sudden, short pulse sounds sharp and crac https://socialmedia.xdme.com/tony/videos-book14/page-061.mp4 https://www.youtube.com/embed/XV-mwtBhqBY 107 2026-10-03T18:09:33+00:00 yes https://xdme.com/watch-book14-q062.html https://xdme.com/book14-thumbs/page-062.jpg Why Does Bubble Wrap Crack When You Squeeze It? Bubble wrap pops because each bubble is a small pocket of trapped air! When you squeeze, the air inside is pushed harder and harder. Then the thin plastic gives way and the air bur https://socialmedia.xdme.com/tony/videos-book14/page-062.mp4 https://www.youtube.com/embed/o4mKMCc9jEc 110 2026-10-03T18:12:14+00:00 yes https://xdme.com/watch-book14-q063.html https://xdme.com/book14-thumbs/page-063.jpg Why Does Velcro Make a Ripping Sound? Velcro rips because thousands of tiny hooks let go of loops one after another! Each little release makes a tiny snap. Thousands of snaps close together blend into a ripping sound. https://socialmedia.xdme.com/tony/videos-book14/page-063.mp4 https://www.youtube.com/embed/pwVA78sxE3o 111 2026-10-03T18:15:21+00:00 yes https://xdme.com/watch-book14-q064.html https://xdme.com/book14-thumbs/page-064.jpg Why Does a Soda Can Go Psst When You Open It? A soda can goes psst because gas rushes out when you open the tab! Inside, the gas is squeezed at a higher pressure than the air outside. Opening the can lets it escape with a hiss https://socialmedia.xdme.com/tony/videos-book14/page-064.mp4 https://www.youtube.com/embed/rPVebzUdVMg 110 2026-10-03T18:18:24+00:00 yes https://xdme.com/watch-book14-q065.html https://xdme.com/book14-thumbs/page-065.jpg Why Do Ice Cubes Crackle in a Drink? Ice cubes crackle because the ice gets stressed when it warms up quickly! The outside swells while the inside stays cold. The ice cracks and tiny air bubbles pop out. https://socialmedia.xdme.com/tony/videos-book14/page-065.mp4 https://www.youtube.com/embed/o7dAjevaFao 110 2026-10-03T18:21:33+00:00 yes https://xdme.com/watch-book14-q066.html https://xdme.com/book14-thumbs/page-066.jpg Why Does Rain Sound Louder on a Metal Roof than on Grass? A metal roof acts like a giant drum when raindrops land on it! The whole thin sheet vibrates, and the sound spreads out. Grass is soft, so it soaks the sound up, so rain sounds sof https://socialmedia.xdme.com/tony/videos-book14/page-066.mp4 https://www.youtube.com/embed/Em8O-SFarIU 112 2026-10-03T18:24:35+00:00 yes https://xdme.com/watch-book14-q067.html https://xdme.com/book14-thumbs/page-067.jpg Why Do Squeaky Doors and Sneakers Squeak? Squeaks come from something called stick-slip! Two surfaces rub together, stick for a moment, and then slip free. This happens over and over, super fast, and that makes the squeak. https://socialmedia.xdme.com/tony/videos-book14/page-067.mp4 https://www.youtube.com/embed/nHkEmgTfVh4 116 2026-10-03T18:27:38+00:00 yes https://xdme.com/watch-book14-q068.html https://xdme.com/book14-thumbs/page-068.jpg Why Does Wind Howl Around a House? Wind howls when it swirls around corners and wires! The swirls peel off one after another at a steady rate. That steady push on the air makes a howl or a whistle. https://socialmedia.xdme.com/tony/videos-book14/page-068.mp4 https://www.youtube.com/embed/C_LNUqN1egE 114 2026-10-03T18:30:10+00:00 yes https://xdme.com/watch-book14-q069.html https://xdme.com/book14-thumbs/page-069.jpg Why Do Footsteps Sound Different on Different Floors? Footsteps sound different because floors bounce, shake, or soak up sound in different ways! Hard floors sound sharp, wood floors boom, and carpet is hushed. Your shoes matter too. https://socialmedia.xdme.com/tony/videos-book14/page-069.mp4 https://www.youtube.com/embed/01e-Apuqmig 116 2026-10-03T18:33:13+00:00 yes https://xdme.com/watch-book14-q070.html https://xdme.com/book14-thumbs/page-070.jpg Why Does a Balloon Squeal When You Let the Air Out? A balloon squeals because the stretched rubber flutters as air rushes by! It works a bit like your lips when you blow a raspberry. Air rushing past it makes it vibrate, and the flu https://socialmedia.xdme.com/tony/videos-book14/page-070.mp4 https://www.youtube.com/embed/MA0PPQXcI-g 111 2026-10-03T18:36:17+00:00 yes https://xdme.com/watch-book14-q071.html https://xdme.com/book14-thumbs/page-071.jpg Why Does a Spoon Hung on a String Sound Like a Big Bell? A spoon on a string sounds like a big bell because the string carries the sound straight to your head! Solid things pass vibrations along better than air does. So you hear deeper, https://socialmedia.xdme.com/tony/videos-book14/page-071.mp4 https://www.youtube.com/embed/L_WHuPEKyy0 111 2026-10-03T18:39:27+00:00 yes https://xdme.com/watch-book14-q072.html https://xdme.com/book14-thumbs/page-072.jpg Why Does a Phone Sound Louder in a Bowl? A phone sounds louder in a bowl because the curved bowl bounces sound toward you! Sound that would have gone sideways gets pointed up and out, toward your ears. The bowl helps gath https://socialmedia.xdme.com/tony/videos-book14/page-072.mp4 https://www.youtube.com/embed/j41DHOVM9d0 106 2026-10-03T18:41:59+00:00 yes https://xdme.com/watch-book14-q073.html https://xdme.com/book14-thumbs/page-073.jpg Why Does Crunchy Food Sound So Loud When You Chew It? Crunchy food sounds loud to you because the sound goes through your jaw bones to your inner ear! Bones carry sound very well. So the chewer hears it much louder than anyone nearby. https://socialmedia.xdme.com/tony/videos-book14/page-073.mp4 https://www.youtube.com/embed/CHFZ8uIqWtk 110 2026-10-03T18:45:02+00:00 yes https://xdme.com/watch-book14-q074.html https://xdme.com/book14-thumbs/page-074.jpg Why Do Cars Need Mufflers? Cars need mufflers because an engine makes very loud pulses of air! A muffler is a metal box that tames those pulses. Much less noise gets out, which keeps streets calmer. https://socialmedia.xdme.com/tony/videos-book14/page-074.mp4 https://www.youtube.com/embed/zlCOHitVcHU 119 2026-10-03T18:48:05+00:00 yes https://xdme.com/watch-book14-q075.html https://xdme.com/book14-thumbs/page-075.jpg Why Does a Jar Lid Pop When You Open It? A jar lid pops because air rushes in when the seal breaks! Inside a sealed jar, the air pressure is lower than outside. The outside air pushes the lid down tight until you open it. https://socialmedia.xdme.com/tony/videos-book14/page-075.mp4 https://www.youtube.com/embed/JKbbRWWaBUg 105 2026-10-03T18:51:07+00:00 yes https://xdme.com/watch-book14-q076.html https://xdme.com/book14-thumbs/page-076.jpg Why Can't Sound Travel Through Empty Space? Sound cannot travel through empty space because it needs something to pass through! Sound is a vibration that moves through air, water, or metal. In space there is almost nothing t https://socialmedia.xdme.com/tony/videos-book14/page-076.mp4 https://www.youtube.com/embed/JXQ377KZJq8 118 2026-10-03T15:09:14+00:00 yes https://xdme.com/watch-book14-q077.html https://xdme.com/book14-thumbs/page-077.jpg Why Does Sound Travel Faster in Water than in Air? Sound travels faster in water than in air because water particles are packed much closer together! A vibration passes from one particle to the next more quickly. Sound moves about https://socialmedia.xdme.com/tony/videos-book14/page-077.mp4 https://www.youtube.com/embed/YsCqrgysOs8 120 2026-10-03T15:09:16+00:00 yes https://xdme.com/watch-book14-q078.html https://xdme.com/book14-thumbs/page-078.jpg Why Does Sound Travel Fastest Through Solid Metal? Sound travels fastest through solid metal because its atoms are held tightly together! They snap back very quickly after a push. So the vibration races from one atom to the next, l https://socialmedia.xdme.com/tony/videos-book14/page-078.mp4 https://www.youtube.com/embed/JMNlf8cgKxU 114 2026-10-03T15:09:49+00:00 yes https://xdme.com/watch-book14-q079.html https://xdme.com/book14-thumbs/page-079.jpg Why Does a Siren Sound Higher as It Comes Toward You and Lower as It Goes Away? A siren sounds higher as it comes toward you because the sound waves get squeezed together! After it passes, the waves are stretched out. This is called the Doppler effect. https://socialmedia.xdme.com/tony/videos-book14/page-079.mp4 https://www.youtube.com/embed/ErejrAFMNFQ 109 2026-10-03T15:12:21+00:00 yes https://xdme.com/watch-book14-q080.html https://xdme.com/book14-thumbs/page-080.jpg Why Can You Hear a Train Through the Rails Before You Hear It in the Air? Sound moves much faster in steel than in air, so a train's rumble can race ahead through the rails! It arrives before the sound that travels through the air. But never go near rail https://socialmedia.xdme.com/tony/videos-book14/page-080.mp4 https://www.youtube.com/embed/IVe2j_9_Usw 116 2026-10-03T15:15:25+00:00 yes https://xdme.com/watch-book14-q081.html https://xdme.com/book14-thumbs/page-081.jpg Why Does a Whip Crack? A whip cracks because its tip moves faster than the speed of sound! A flick sends a loop racing down the whip. At the thin end, it makes a tiny sonic boom. https://socialmedia.xdme.com/tony/videos-book14/page-081.mp4 https://www.youtube.com/embed/GSYeRFbyWsQ 103 2026-10-03T15:18:30+00:00 yes https://xdme.com/watch-book14-q082.html https://xdme.com/book14-thumbs/page-082.jpg Why Does a Jet Flying Faster than Sound Make a Boom? A jet flying faster than sound makes a boom because its sound waves pile up into a shock wave! When that wave passes you, your ears hear a sudden loud boom. It is called a sonic bo https://socialmedia.xdme.com/tony/videos-book14/page-082.mp4 https://www.youtube.com/embed/SD2PSPMUPHA 108 2026-10-03T15:21:34+00:00 yes https://xdme.com/watch-book14-q083.html https://xdme.com/book14-thumbs/page-083.jpg Why Does Sound Carry Farther on a Cold, Still Morning? Sound carries farther on a cold, still morning because the cold air bends it back down! Warm air lets sound move faster, and cold air slows it. Calm, quiet air helps too. https://socialmedia.xdme.com/tony/videos-book14/page-083.mp4 https://www.youtube.com/embed/0QubzBPPBJI 112 2026-10-03T15:24:37+00:00 yes https://xdme.com/watch-book14-q084.html https://xdme.com/book14-thumbs/page-084.jpg Why Do Voices Carry So Far Across a Calm Lake? Voices carry far across a calm lake because the smooth water bounces sound instead of soaking it up! Cool air just above the water also bends sound back down. And there is nothing https://socialmedia.xdme.com/tony/videos-book14/page-084.mp4 https://www.youtube.com/embed/b3WAfKSjqNU 110 2026-10-03T15:27:20+00:00 yes https://xdme.com/watch-book14-q085.html https://xdme.com/book14-thumbs/page-085.jpg Why Do Voices Sound So Strange Underwater? Voices sound strange underwater because our ears are built for sound that arrives through air! Underwater, sound comes through the water and the bones of your head. Water and air a https://socialmedia.xdme.com/tony/videos-book14/page-085.mp4 https://www.youtube.com/embed/-vlMBjkkTUA 111 2026-10-03T15:30:23+00:00 yes https://xdme.com/watch-book14-q086.html https://xdme.com/book14-thumbs/page-086.jpg Why Is It Hard to Tell Where a Sound Is Coming From Underwater? Underwater it is hard to tell where a sound comes from, because sound travels so fast! The time difference between your two ears becomes tiny. Your brain gets confused about the di https://socialmedia.xdme.com/tony/videos-book14/page-086.mp4 https://www.youtube.com/embed/7z_6FCPgf-4 108 2026-10-03T15:33:25+00:00 yes https://xdme.com/watch-book14-q087.html https://xdme.com/book14-thumbs/page-087.jpg Why Does Bass Travel Through Walls When High Sounds Don't? Bass travels through walls because low sounds have long, slow waves that shake a whole wall at once! High sounds have short waves that bounce off or get soaked up. So bass slips th https://socialmedia.xdme.com/tony/videos-book14/page-087.mp4 https://www.youtube.com/embed/reIBviIoDjw 108 2026-10-03T15:36:29+00:00 yes https://xdme.com/watch-book14-q088.html https://xdme.com/book14-thumbs/page-088.jpg Why Is Sound a Little Faster on a Hot Day? Sound is a little faster on a hot day because warm particles move faster! They bump into each other more quickly. So the bumps get passed along sooner, even though you cannot see i https://socialmedia.xdme.com/tony/videos-book14/page-088.mp4 https://www.youtube.com/embed/QnQrlfhEATs 126 2026-10-03T15:40:16+00:00 yes https://xdme.com/watch-book14-q089.html https://xdme.com/book14-thumbs/page-089.jpg How Fast Does Sound Travel? Sound travels about 343 meters every second in air at room temperature! That is about 1,235 kilometers an hour. It is fast, but light is much, much faster than that. https://socialmedia.xdme.com/tony/videos-book14/page-089.mp4 https://www.youtube.com/embed/qVFgWkYiQLQ 125 2026-10-03T15:43:27+00:00 yes https://xdme.com/watch-book14-q090.html https://xdme.com/book14-thumbs/page-090.jpg Why Can a Long Tube Carry a Whisper? A long tube can carry a whisper because it keeps the sound from spreading out! The sound waves bounce along inside the walls and stay together. So more of the sound reaches the oth https://socialmedia.xdme.com/tony/videos-book14/page-090.mp4 https://www.youtube.com/embed/tGqGQClW6xw 113 2026-10-03T15:46:31+00:00 yes https://xdme.com/watch-book14-q091.html https://xdme.com/book14-thumbs/page-091.jpg Why Can Astronauts Talk to Each Other on a Spacewalk? Astronauts can talk on a spacewalk because they use radio instead of sound traveling through air! A microphone turns their voice into an electrical signal. A radio sends it as radi https://socialmedia.xdme.com/tony/videos-book14/page-091.mp4 https://www.youtube.com/embed/uXiuGn61AQs 115 2026-10-03T15:49:34+00:00 yes https://xdme.com/watch-book14-q092.html https://xdme.com/book14-thumbs/page-092.jpg Why Do Scuba Divers Use Hand Signals Instead of Talking? Scuba divers use hand signals because they cannot talk with a breathing tool in their mouths! Sounds underwater are also hard to understand. Hand signals work in any water and any https://socialmedia.xdme.com/tony/videos-book14/page-092.mp4 https://www.youtube.com/embed/0qaIyY-rZt4 116 2026-10-03T15:52:47+00:00 yes https://xdme.com/watch-book14-q093.html https://xdme.com/book14-thumbs/page-093.jpg Why Do Highways Have Tall Walls Beside Them? Tall walls beside highways are noise barriers that keep traffic sound away from homes! They block, reflect, and sometimes absorb sound waves. So less noise reaches the people nearb https://socialmedia.xdme.com/tony/videos-book14/page-093.mp4 https://www.youtube.com/embed/zB5LT17FQyM 114 2026-10-03T15:55:50+00:00 yes https://xdme.com/watch-book14-q094.html https://xdme.com/book14-thumbs/page-094.jpg Why Can a Whisper Travel Along a Curved Wall? A whisper can travel along a curved wall because the sound clings to the curve! The waves bounce along the wall again and again. They stay close to the surface instead of spreading https://socialmedia.xdme.com/tony/videos-book14/page-094.mp4 https://www.youtube.com/embed/gwK0WxuKxsE 113 2026-10-03T15:58:52+00:00 yes https://xdme.com/watch-book14-q095.html https://xdme.com/book14-thumbs/page-095.jpg Why Does a Plane Seem to Be in a Different Place than Its Sound? A plane seems to be in a different place than its sound because sound is slower than the plane! What you hear left the plane a while ago, even though the plane looks close. By the https://socialmedia.xdme.com/tony/videos-book14/page-095.mp4 https://www.youtube.com/embed/J-abzTc3Yw8 107 2026-10-03T16:01:37+00:00 yes https://xdme.com/watch-book14-q096.html https://xdme.com/book14-thumbs/page-096.jpg Why Does a Crowd of People Sound Like a Steady Roar? A crowd sounds like a steady roar because many voices blend into one smooth noise! The voices are at different pitches and at different times. So no single voice stands out. https://socialmedia.xdme.com/tony/videos-book14/page-096.mp4 https://www.youtube.com/embed/OpWWpJWbK2Q 110 2026-10-03T16:04:44+00:00 yes https://xdme.com/watch-book14-q097.html https://xdme.com/book14-thumbs/page-097.jpg Why Do Voices Sound Thin High Up on a Mountain? Voices can sound thin high on a mountain because thin air and open spaces make sound fade fast! Up high, the air has fewer particles in each puff. There are also few walls to bounc https://socialmedia.xdme.com/tony/videos-book14/page-097.mp4 https://www.youtube.com/embed/EJO7maaG79Q 109 2026-10-03T16:08:27+00:00 yes https://xdme.com/watch-book14-q098.html https://xdme.com/book14-thumbs/page-098.jpg Why Does Snow Squeak When It Is Very Cold? Snow squeaks in very cold weather because the crystals are hard and dry! When you step on them, they crush and rub in rapid-fire. All those tiny cracks together make the squeak. https://socialmedia.xdme.com/tony/videos-book14/page-098.mp4 https://www.youtube.com/embed/cGS0yFQ7QIQ 112 2026-10-03T16:11:31+00:00 yes https://xdme.com/watch-book14-q099.html https://xdme.com/book14-thumbs/page-099.jpg Why Does a Frozen Lake Sometimes Make Strange Pew-Pew Sounds? A frozen lake can make pew-pew sounds because cracking ice sends waves through the ice! High notes travel faster than low notes in ice. So the sound arrives as a falling zap. https://socialmedia.xdme.com/tony/videos-book14/page-099.mp4 https://www.youtube.com/embed/TlkwjkIFIes 108 2026-10-03T16:14:45+00:00 yes https://xdme.com/watch-book14-q100.html https://xdme.com/book14-thumbs/page-100.jpg Why Do Some Beaches Have Singing Sand? Singing sand makes sounds because layers of sand grains slide over each other together! That slipping makes a steady vibration. You hear it as a squeak, a hum, or even a boom. https://socialmedia.xdme.com/tony/videos-book14/page-100.mp4 https://www.youtube.com/embed/YVuGC7fLcdc 111 2026-10-03T16:17:49+00:00 yes https://xdme.com/watch-book14-q101.html https://xdme.com/book14-thumbs/page-101.jpg Why Can You Hear a Clear Echo in a Canyon but Not in a Forest? An echo is a sound that bounces off a hard surface and comes back to you! In a canyon, tall flat rock walls send your voice straight back. In a forest, trees and leaves scatter and https://socialmedia.xdme.com/tony/videos-book14/page-101.mp4 https://www.youtube.com/embed/zlYZ34lDHZY 119 2026-10-03T16:20:51+00:00 yes https://xdme.com/watch-book14-q102.html https://xdme.com/book14-thumbs/page-102.jpg Why Does Your Voice Sound Bigger in a Bathroom? Your voice sounds bigger in a bathroom because hard walls bounce it back and forth! Those quick bounces blend with your real voice, so it seems fuller. This blending is called reve https://socialmedia.xdme.com/tony/videos-book14/page-102.mp4 https://www.youtube.com/embed/qi4eJ8EIYaM 113 2026-10-03T16:23:53+00:00 yes https://xdme.com/watch-book14-q103.html https://xdme.com/book14-thumbs/page-103.jpg Why Does a Shout in a Tunnel Keep Ringing? A sound in a tunnel keeps ringing because the walls, floor, and ceiling are all hard! The sound bounces back and forth along the whole tunnel. Each bounce loses a little energy, so https://socialmedia.xdme.com/tony/videos-book14/page-103.mp4 https://www.youtube.com/embed/CeceIxiULHI 115 2026-10-03T16:27:31+00:00 yes https://xdme.com/watch-book14-q104.html https://xdme.com/book14-thumbs/page-104.jpg How Can You Use an Echo to Measure Distance? An echo is a sound's round trip, and you can use its trip time to measure distance! The sound goes to a wall and comes back, so it travels there and back. Time it, and a little mat https://socialmedia.xdme.com/tony/videos-book14/page-104.mp4 https://www.youtube.com/embed/WulSAU-1no8 117 2026-10-03T16:30:04+00:00 yes https://xdme.com/watch-book14-q105.html https://xdme.com/book14-thumbs/page-105.jpg Why Do Car Parking Sensors Beep Faster as the Car Gets Closer? Parking sensors beep faster because the echo returns sooner when you get closer! The sensors send out short bursts of sound too high for us to hear. The car's computer turns a shor https://socialmedia.xdme.com/tony/videos-book14/page-105.mp4 https://www.youtube.com/embed/3q6HrM1Mnq8 115 2026-10-03T16:33:07+00:00 yes https://xdme.com/watch-book14-q106.html https://xdme.com/book14-thumbs/page-106.jpg How Can Some People Use Clicking Sounds to Sense Walls and Doorways? Some people use soft clicking sounds to sense walls and doorways. This is called echolocation! The clicks bounce off nearby things and come back as echoes, and the brain learns to https://socialmedia.xdme.com/tony/videos-book14/page-106.mp4 https://www.youtube.com/embed/01MU7jHmLIQ 113 2026-10-03T16:39:17+00:00 yes https://xdme.com/watch-book14-q107.html https://xdme.com/book14-thumbs/page-107.jpg What Is Ultrasound, and How Do Bats and Doctors Use It? Ultrasound is sound with a pitch so high that people cannot hear it! The waves are still real, and they travel through air, water, and the body. Bats, dolphins, doctors, and many m https://socialmedia.xdme.com/tony/videos-book14/page-107.mp4 https://www.youtube.com/embed/tglz2bwuf8E 119 2026-10-03T16:42:51+00:00 yes https://xdme.com/watch-book14-q108.html https://xdme.com/book14-thumbs/page-108.jpg Why Can a Shout Take Seconds to Bounce Back From a Far-Away Mountain? A shout takes seconds to come back from a faraway mountain because sound needs time to travel! Sound is fast, but mountains can be very far away. The farther the mountain, the long https://socialmedia.xdme.com/tony/videos-book14/page-108.mp4 https://www.youtube.com/embed/7KSZz28gKJ0 117 2026-10-03T16:45:24+00:00 yes https://xdme.com/watch-book14-q109.html https://xdme.com/book14-thumbs/page-109.jpg Why Do Recording Studios Have Foam Wedges on the Walls? Recording studios have foam wedges on the walls to soak up sound instead of letting it bounce! With fewer echoes, a studio can record clear sound without a roomy ring. The wedges a https://socialmedia.xdme.com/tony/videos-book14/page-109.mp4 https://www.youtube.com/embed/8PlvTAJV-pw 113 2026-10-03T16:48:27+00:00 yes https://xdme.com/watch-book14-q110.html https://xdme.com/book14-thumbs/page-110.jpg Why Can't You Hear an Echo in a Small Room? You cannot hear a clear echo in a small room because the walls are so close! The echo comes back almost at once and blends with your voice. Your ears cannot separate it, so the sou https://socialmedia.xdme.com/tony/videos-book14/page-110.mp4 https://www.youtube.com/embed/hcGp-dLv0Ps 113 2026-10-03T16:51:30+00:00 yes https://xdme.com/watch-book14-q111.html https://xdme.com/book14-thumbs/page-111.jpg Why Does Clapping Between Two Flat Walls Make a Zinging Sound? Clapping between two flat walls makes a zinging sound called a flutter echo! The sound bounces back and forth between the walls, and each bounce is a tiny echo. They come so quickl https://socialmedia.xdme.com/tony/videos-book14/page-111.mp4 https://www.youtube.com/embed/qEY6XXg--uk 113 2026-10-03T16:54:35+00:00 yes https://xdme.com/watch-book14-q112.html https://xdme.com/book14-thumbs/page-112.jpg Why Can Tapping a Wall Tell You Where the Hidden Beams Are? Tapping a wall can tell you where the hidden beams are, because hollow and solid parts sound different! Behind a wall there are hollow spaces and hard wooden beams. By tapping and https://socialmedia.xdme.com/tony/videos-book14/page-112.mp4 https://www.youtube.com/embed/RlUFyIwtKac 112 2026-10-03T16:57:37+00:00 yes https://xdme.com/watch-book14-q113.html https://xdme.com/book14-thumbs/page-113.jpg Why Do People Tap Things to Check If They Are Cracked or Hollow? People tap things to check if they are cracked or hollow, because flaws change how an object rings! A solid object rings clearly when you tap it. A crack or a hollow space makes a https://socialmedia.xdme.com/tony/videos-book14/page-113.mp4 https://www.youtube.com/embed/NMAQKfHGPCE 108 2026-10-03T17:00:56+00:00 yes https://xdme.com/watch-book14-q114.html https://xdme.com/book14-thumbs/page-114.jpg How Do Plumbers Find a Leak in a Pipe Using Sound? Plumbers can find a leak in a pipe by listening for the sound the leak makes! Water under pressure squirts through a tiny crack with a hissing noise. That noise travels along the p https://socialmedia.xdme.com/tony/videos-book14/page-114.mp4 https://www.youtube.com/embed/NuREiqkgH4E 112 2026-10-03T17:04:02+00:00 yes https://xdme.com/watch-book14-q115.html https://xdme.com/book14-thumbs/page-115.jpg How Can Scientists Use Sound to Measure How Thick Ice Is? Scientists can measure how thick ice is by sending sound into it and timing the echo! A short pulse of sound goes down and bounces off the bottom of the ice. The longer the echo ta https://socialmedia.xdme.com/tony/videos-book14/page-115.mp4 https://www.youtube.com/embed/p_SasgB6fQo 115 2026-10-03T17:07:13+00:00 yes https://xdme.com/watch-book14-q116.html https://xdme.com/book14-thumbs/page-116.jpg Why Can You Tell How Big a Room Is with Your Eyes Closed? You can tell how big a room is with your eyes closed because every room has its own sound! A big room has longer echoes and a lingering sound. A small room sounds tight and dry. https://socialmedia.xdme.com/tony/videos-book14/page-116.mp4 https://www.youtube.com/embed/hfSN5O99DlA 109 2026-10-03T17:09:46+00:00 yes https://xdme.com/watch-book14-q117.html https://xdme.com/book14-thumbs/page-117.jpg Why Do You Sometimes Hear Your Own Voice Echo on a Phone Call? You hear your own voice echo on a phone call because your words make a round trip! They travel to your friend, come out of their speaker, and get picked up by their microphone. The https://socialmedia.xdme.com/tony/videos-book14/page-117.mp4 https://www.youtube.com/embed/NkGEJwX3HWU 112 2026-10-03T17:12:48+00:00 yes https://xdme.com/watch-book14-q118.html https://xdme.com/book14-thumbs/page-118.jpg Why Did Sailors Blow a Horn Near Cliffs and Listen for the Echo? Sailors blew a horn near cliffs to use the echo as a safety check in fog! When they could not see the shore, the echo told them how close it was. A quick echo meant a close cliff, https://socialmedia.xdme.com/tony/videos-book14/page-118.mp4 https://www.youtube.com/embed/PoBQjRhGWZg 114 2026-10-03T17:15:51+00:00 yes https://xdme.com/watch-book14-q119.html https://xdme.com/book14-thumbs/page-119.jpg Why Does Your Voice Sound Hollow Inside a Bucket or a Big Pipe? Your voice sounds hollow in a bucket or a big pipe because the air inside rings along with you! A bucket or pipe is a small hollow space with hard sides. Your voice bounces around https://socialmedia.xdme.com/tony/videos-book14/page-119.mp4 https://www.youtube.com/embed/tD92J_bdno0 111 2026-10-03T17:18:54+00:00 yes https://xdme.com/watch-book14-q120.html https://xdme.com/book14-thumbs/page-120.jpg How Can Sound Waves Clean Eyeglasses? Sound waves clean eyeglasses in a machine called an ultrasonic cleaner! It is a small tank of soapy water with a device that sends in sound too high to hear. The sound waves make t https://socialmedia.xdme.com/tony/videos-book14/page-120.mp4 https://www.youtube.com/embed/S9XKh5KpDio 114 2026-10-03T17:22:12+00:00 yes https://xdme.com/watch-book14-q121.html https://xdme.com/book14-thumbs/page-121.jpg Can a Singer Really Break a Glass with Their Voice? A singer really can break a glass with their voice, but only in rare cases! Every glass has its own natural pitch that it likes to ring at. Please do not try this at home, since br https://socialmedia.xdme.com/tony/videos-book14/page-121.mp4 https://www.youtube.com/embed/Npm3Jjfxtao 115 2026-10-03T17:24:45+00:00 yes https://xdme.com/watch-book14-q122.html https://xdme.com/book14-thumbs/page-122.jpg Why Can Sound Hold Tiny Bits of Foam in Mid-Air? Sound can hold tiny bits of foam in mid-air. This is called acoustic levitation! Sound waves squeeze the air back and forth very strongly, and in the right spots that pushing balan https://socialmedia.xdme.com/tony/videos-book14/page-122.mp4 https://www.youtube.com/embed/Eq5JQ-aY8_s 113 2026-10-03T17:27:50+00:00 yes https://xdme.com/watch-book14-q123.html https://xdme.com/book14-thumbs/page-123.jpg Why Does Sand Make Patterns on a Vibrating Plate? Sand makes patterns on a vibrating plate because some parts shake and some parts stay still! The sand bounces away from the shaking parts. It ends up on the still lines, and draws https://socialmedia.xdme.com/tony/videos-book14/page-123.mp4 https://www.youtube.com/embed/-RePgP7yoIA 113 2026-10-03T17:30:54+00:00 yes https://xdme.com/watch-book14-q124.html https://xdme.com/book14-thumbs/page-124.jpg Why Do Some Backing-Up Trucks Go Shh-Shh Instead of Beep-Beep? Some backing-up trucks go shh-shh instead of beep-beep because a shh sound is easier to locate! A beep has just one pitch, and it is hard to tell where it comes from. A shh-shh has https://socialmedia.xdme.com/tony/videos-book14/page-124.mp4 https://www.youtube.com/embed/NLWt91RFr_M 113 2026-10-03T17:33:56+00:00 yes https://xdme.com/watch-book14-q125.html https://xdme.com/book14-thumbs/page-125.jpg Why Can Echoes Make a Speech Hard to Understand? Echoes make a speech hard to understand because each sound lingers and overlaps the next one! The words blur together like wet paint. In a big echoey room, the echo of the first wo https://socialmedia.xdme.com/tony/videos-book14/page-125.mp4 https://www.youtube.com/embed/b51QY1aFKTw 110 2026-10-03T17:36:36+00:00 yes https://xdme.com/watch-book14-q126.html https://xdme.com/book14-thumbs/page-126.jpg What Do the Tiny Hair Cells in Your Ears Do, and Why Can't They Grow Back? Tiny hair cells in your inner ear turn sound into signals for your brain! They cannot grow back in people, so loud noise can cause lasting harm. That is why protecting your ears ma https://socialmedia.xdme.com/tony/videos-book14/page-126.mp4 https://www.youtube.com/embed/-VAgy40oSnU 114 2026-10-03T17:39:46+00:00 yes https://xdme.com/watch-book14-q127.html https://xdme.com/book14-thumbs/page-127.jpg Why Do People Who Work Near Loud Machines Wear Ear Protection? People who work near loud machines wear ear protection to keep their hearing strong for life! Lawn mowers, power saws, and drills can be so loud that long listening tires out the t https://socialmedia.xdme.com/tony/videos-book14/page-127.mp4 https://www.youtube.com/embed/KILWlJweuoE 114 2026-10-03T17:42:57+00:00 yes https://xdme.com/watch-book14-q128.html https://xdme.com/book14-thumbs/page-128.jpg Why Do Ear Defenders Matter at Fireworks, Motor Races, and Loud Concerts? Ear defenders matter at fireworks, motor races, and loud concerts because those sounds are very strong, and they can be too much for your ears! Ear defenders turn the volume down s https://socialmedia.xdme.com/tony/videos-book14/page-128.mp4 https://www.youtube.com/embed/hmQ2VwIL9F4 113 2026-10-03T17:46:00+00:00 yes https://xdme.com/watch-book14-q129.html https://xdme.com/book14-thumbs/page-129.jpg How Can You Tell If Your Headphones Are Too Loud? You can tell your headphones are too loud with a simple rule! If a friend an arm's length away can hear your music, it is too loud. The same goes if you cannot hear them talking. https://socialmedia.xdme.com/tony/videos-book14/page-129.mp4 https://www.youtube.com/embed/wY8Is8HS3Cg 107 2026-10-03T17:48:32+00:00 yes https://xdme.com/watch-book14-q130.html https://xdme.com/book14-thumbs/page-130.jpg Why Do Listening Breaks Help Your Ears? Listening breaks help your ears because the hair cells get tired after a lot of sound! Resting them in a quiet place gives them time to recover. A quiet break helps your whole body https://socialmedia.xdme.com/tony/videos-book14/page-130.mp4 https://www.youtube.com/embed/zolQOorzUJ0 111 2026-10-03T17:51:36+00:00 yes https://xdme.com/watch-book14-q131.html https://xdme.com/book14-thumbs/page-131.jpg Why Do Your Ears Sometimes Ring After a Very Loud Noise? Your ears can ring after a very loud noise because the tiny hair cells in them got tired out! The ringing is your ears' way of saying, "that was too loud." It is a helpful reminder https://socialmedia.xdme.com/tony/videos-book14/page-131.mp4 https://www.youtube.com/embed/lNCvEwMzwZ8 109 2026-10-03T17:54:40+00:00 yes https://xdme.com/watch-book14-q132.html https://xdme.com/book14-thumbs/page-132.jpg Why Do Hearing Tests Use Beeps in Headphones? Hearing tests use beeps in headphones to find the quietest sound you can hear! The test is called an audiogram, and it does not hurt at all. It checks each ear, one pitch at a time https://socialmedia.xdme.com/tony/videos-book14/page-132.mp4 https://www.youtube.com/embed/IDU4Q8h9uXs 111 2026-10-03T17:57:43+00:00 yes https://xdme.com/watch-book14-q133.html https://xdme.com/book14-thumbs/page-133.jpg How Does a Hearing Aid Work? A hearing aid is a tiny device worn in or behind the ear that makes sounds easier to hear! It has a microphone, a small computer, and a tiny speaker. Many people of all ages use th https://socialmedia.xdme.com/tony/videos-book14/page-133.mp4 https://www.youtube.com/embed/9GAg_o7M8qw 110 2026-10-03T18:00:46+00:00 yes https://xdme.com/watch-book14-q134.html https://xdme.com/book14-thumbs/page-134.jpg Why Do Captions on Videos Help Lots of People? Captions on videos help lots of people because they show the words on screen! They help people who are Deaf or hard of hearing follow along. They help many other people too. https://socialmedia.xdme.com/tony/videos-book14/page-134.mp4 https://www.youtube.com/embed/iVYDen4Ir9k 113 2026-10-03T18:03:49+00:00 yes https://xdme.com/watch-book14-q135.html https://xdme.com/book14-thumbs/page-135.jpg Why Do Ears Make Earwax? Ears make earwax to keep themselves clean and healthy! Earwax, also called cerumen, is a sticky, slightly oily layer in your ear canal. It is useful, not dirty. https://socialmedia.xdme.com/tony/videos-book14/page-135.mp4 https://www.youtube.com/embed/gqYuddJW6yk 111 2026-10-03T18:07:02+00:00 yes https://xdme.com/watch-book14-q136.html https://xdme.com/book14-thumbs/page-136.jpg Why Shouldn't You Poke Anything Into Your Ears? You should not poke anything into your ears because the eardrum inside is thin and delicate! Cotton swabs, pencils, and fingers can scratch the ear canal. Your ears clean themselve https://socialmedia.xdme.com/tony/videos-book14/page-136.mp4 https://www.youtube.com/embed/hSyhFibPIig 113 2026-10-03T18:09:36+00:00 yes https://xdme.com/watch-book14-q137.html https://xdme.com/book14-thumbs/page-137.jpg Why Are Our Outer Ears Shaped Like Curly Funnels? Your outer ears are shaped like curly funnels to catch sound and help you find where it comes from! The curves and ridges catch sound waves and bounce them into the ear canal. They https://socialmedia.xdme.com/tony/videos-book14/page-137.mp4 https://www.youtube.com/embed/cZ7vAuKnUHY 109 2026-10-03T18:12:45+00:00 yes https://xdme.com/watch-book14-q138.html https://xdme.com/book14-thumbs/page-138.jpg Why Do Some Crosswalks Beep or Chirp? Some crosswalks beep or chirp so that people who are blind or have trouble seeing know when it is safe to cross! The sounds say when the walk signal is on. They help everyone cross https://socialmedia.xdme.com/tony/videos-book14/page-138.mp4 https://www.youtube.com/embed/BKwFNPiqU4A 109 2026-10-03T18:15:22+00:00 yes https://xdme.com/watch-book14-q139.html https://xdme.com/book14-thumbs/page-139.jpg Why Do Some Alarms Flash a Light as Well as Make a Sound? Some alarms flash a light as well as make a sound because light is another way to share a warning! A flashing light can warn people who are Deaf or hard of hearing. It can also hel https://socialmedia.xdme.com/tony/videos-book14/page-139.mp4 https://www.youtube.com/embed/9nEIQ0CEwRw 116 2026-10-03T18:18:29+00:00 yes https://xdme.com/watch-book14-q140.html https://xdme.com/book14-thumbs/page-140.jpg Why Does Background Noise Make It Harder to Focus? Background noise makes it harder to focus because your brain only has so much attention to share! When there is chatter around, your brain tries to listen to it and to do your work https://socialmedia.xdme.com/tony/videos-book14/page-140.mp4 https://www.youtube.com/embed/nr8ckA3tTkQ 112 2026-10-03T18:21:01+00:00 yes https://xdme.com/watch-book14-q141.html https://xdme.com/book14-thumbs/page-141.jpg Why Is It Risky to Wear Headphones While Biking or Crossing the Street? It is risky to wear headphones while biking or crossing the street because you may not hear warning sounds! Your ears are part of your safety team. Keep headphones off when you are https://socialmedia.xdme.com/tony/videos-book14/page-141.mp4 https://www.youtube.com/embed/crmazmjQdjA 112 2026-10-03T18:24:04+00:00 yes https://xdme.com/watch-book14-q142.html https://xdme.com/book14-thumbs/page-142.jpg Why Can Younger People Hear Some Sounds That Adults Can't? Younger people can hear some high sounds that adults can't! Babies and young people can hear higher pitches than most adults. This is a normal part of getting older. https://socialmedia.xdme.com/tony/videos-book14/page-142.mp4 https://www.youtube.com/embed/EMw1zlqFFS8 113 2026-10-03T18:27:39+00:00 yes https://xdme.com/watch-book14-q143.html https://xdme.com/book14-thumbs/page-143.jpg How Can You Make a Noisy Room Quieter? You can make a noisy room quieter by adding soft things that absorb sound! Rugs, curtains, cushions, and bookshelves full of books all soak up sound. Small changes can add up. https://socialmedia.xdme.com/tony/videos-book14/page-143.mp4 https://www.youtube.com/embed/3KZjl17JvD0 110 2026-10-03T18:30:12+00:00 yes https://xdme.com/watch-book14-q144.html https://xdme.com/book14-thumbs/page-144.jpg What Is White Noise, and Why Does It Hide Other Sounds? White noise is a sound that has every pitch mixed in at about the same strength! It sounds like shhhh or the hiss of a TV between channels. It covers up sudden sounds, so they stan https://socialmedia.xdme.com/tony/videos-book14/page-144.mp4 https://www.youtube.com/embed/mm1KKo43DKY 109 2026-10-03T18:33:15+00:00 yes https://xdme.com/watch-book14-q145.html https://xdme.com/book14-thumbs/page-145.jpg How Do Vibrating Alarm Clocks and Flashing Doorbells Help People Who Are Deaf or Hard of Hearing? People who are Deaf or hard of hearing often use alerts that they can see or feel instead of sounds! A vibrating alarm clock can shake the bed or pillow. A doorbell can flash a lig https://socialmedia.xdme.com/tony/videos-book14/page-145.mp4 https://www.youtube.com/embed/J4pPEGrGwIg 113 2026-10-03T18:36:20+00:00 yes https://xdme.com/watch-book14-q146.html https://xdme.com/book14-thumbs/page-146.jpg How Can People Who Are Deaf or Hard of Hearing Enjoy Music? People who are Deaf or hard of hearing can enjoy music in many ways! Music is more than just hearing sound. Deep beats make strong vibrations that hands and feet can feel, lights a https://socialmedia.xdme.com/tony/videos-book14/page-146.mp4 https://www.youtube.com/embed/YXcLzn3sOaQ 112 2026-10-03T18:39:28+00:00 yes https://xdme.com/watch-book14-q147.html https://xdme.com/book14-thumbs/page-147.jpg Why Should You Tell a Grown-Up If Your Ears Hurt or Sounds Seem Muffled? You should tell a grown-up if your ears hurt or sounds seem muffled, because something may be wrong! Most ear troubles can be treated. Seeing a doctor early helps. https://socialmedia.xdme.com/tony/videos-book14/page-147.mp4 https://www.youtube.com/embed/0BGP0POqkxg 108 2026-10-03T18:42:00+00:00 yes https://xdme.com/watch-book14-q148.html https://xdme.com/book14-thumbs/page-148.jpg Why Do Some Toys and Kids' Headphones Have a Volume Limit? Some toys and kids' headphones have a volume limit to protect young ears! Many have a limit of about 85 decibels, and some use lower limits. A limit stops the sound from going any https://socialmedia.xdme.com/tony/videos-book14/page-148.mp4 https://www.youtube.com/embed/Zy6yCYq4I-4 115 2026-10-03T18:45:03+00:00 yes https://xdme.com/watch-book14-q149.html https://xdme.com/book14-thumbs/page-149.jpg Why Do Some Animals Have Giant Ears? Some animals have giant ears because big ears catch faint sounds from far away! A bigger ear collects more sound waves, like a larger bucket collects more rain. Many animals can tu https://socialmedia.xdme.com/tony/videos-book14/page-149.mp4 https://www.youtube.com/embed/GGav02LQPmc 113 2026-10-03T18:48:06+00:00 yes https://xdme.com/watch-book14-q150.html https://xdme.com/book14-thumbs/page-150.jpg What Is the Faintest Sound a Person Can Hear? The faintest sound a person can hear is called the threshold of hearing! For most healthy people, that is about zero decibels at middle pitches. Our ears are amazingly sensitive. https://socialmedia.xdme.com/tony/videos-book14/page-150.mp4 https://www.youtube.com/embed/VAobR_xi26U 112 2026-10-03T18:51:10+00:00 yes https://xdme.com/watch-book15-q001.html https://xdme.com/book15-thumbs/page-001.jpg Why Do We Call a Machine a Robot? We call a machine a robot when it can sense, decide, and act! Sensors notice the world around it. Its computer brain follows a program to choose what to do. https://socialmedia.xdme.com/tony/videos-book15/page-001.mp4 https://www.youtube.com/embed/HXukbH_e4Q4 115 2026-10-03T19:10:28+00:00 yes https://xdme.com/watch-book15-q002.html https://xdme.com/book15-thumbs/page-002.jpg Why Isn't a Remote-Control Car a Robot? A remote-control car is not a robot because you do the thinking! You watch where it goes, and you choose every turn. The car just obeys, while a robot does some sensing and decidin https://socialmedia.xdme.com/tony/videos-book15/page-002.mp4 https://www.youtube.com/embed/zsPPiB0wcfI 116 2026-10-03T19:10:30+00:00 yes https://xdme.com/watch-book15-q003.html https://xdme.com/book15-thumbs/page-003.jpg Why Is a Toaster Not a Robot but a Robot Vacuum Is? A toaster does the same thing no matter what, but a robot vacuum looks around and chooses! A toaster follows a timer or a heat setting. A vacuum senses and decides, and that is wha https://socialmedia.xdme.com/tony/videos-book15/page-003.mp4 https://www.youtube.com/embed/_7vHjcId9MA 113 2026-10-03T19:10:32+00:00 yes https://xdme.com/watch-book15-q004.html https://xdme.com/book15-thumbs/page-004.jpg Where Does the Word Robot Come From? The word robot comes from a Czech word, robota, which means hard work! A writer named Karel Čapek used it in a play in 1920. The word was invented before real robots existed, so st https://socialmedia.xdme.com/tony/videos-book15/page-004.mp4 https://www.youtube.com/embed/bXRYgZsMv94 115 2026-10-03T19:10:42+00:00 yes https://xdme.com/watch-book15-q005.html https://xdme.com/book15-thumbs/page-005.jpg Why Do Many Robots Look Nothing Like People? Robots are built to do a job, so their shapes copy their jobs! A floor cleaner is flat and round, a factory robot is an arm that reaches, and a rover has wheels. Engineers call thi https://socialmedia.xdme.com/tony/videos-book15/page-005.mp4 https://www.youtube.com/embed/KLuX0Kgq-_0 113 2026-10-03T19:11:40+00:00 yes https://xdme.com/watch-book15-q006.html https://xdme.com/book15-thumbs/page-006.jpg Why Do Engineers Sometimes Build Robots in Human Shapes? Engineers sometimes build human-shaped robots because the world is built for people! Stairs, doors, tools, and handles are made for human bodies. A robot shaped like us can use the https://socialmedia.xdme.com/tony/videos-book15/page-006.mp4 https://www.youtube.com/embed/ABwWYjJwnxU 111 2026-10-03T19:14:42+00:00 yes https://xdme.com/watch-book15-q007.html https://xdme.com/book15-thumbs/page-007.jpg Why Does Every Robot Need a Body, a Brain, and a Power Source? Every robot needs a body, a brain, and a power source! The body moves and does the work, the brain makes the choices, and the power gives energy to everything. Take away any one of https://socialmedia.xdme.com/tony/videos-book15/page-007.mp4 https://www.youtube.com/embed/Qb6T6Wv-_7k 112 2026-10-03T19:17:44+00:00 yes https://xdme.com/watch-book15-q008.html https://xdme.com/book15-thumbs/page-008.jpg How Does a Robot Get the Energy to Move? Most robots get their energy from batteries! A battery stores energy that can turn into electricity. That electricity runs the motors and the computer, so the robot can move, sense https://socialmedia.xdme.com/tony/videos-book15/page-008.mp4 https://www.youtube.com/embed/WkqPhtyRpGc 121 2026-10-03T19:20:55+00:00 yes https://xdme.com/watch-book15-q009.html https://xdme.com/book15-thumbs/page-009.jpg What Does a Robot's Brain Actually Do? A robot's brain is a small computer that follows a program! It reads numbers from the sensors and decides what to tell the motors. It does not think like a person does. https://socialmedia.xdme.com/tony/videos-book15/page-009.mp4 https://www.youtube.com/embed/xu1oqsHiWWI 117 2026-10-03T19:24:29+00:00 yes https://xdme.com/watch-book15-q010.html https://xdme.com/book15-thumbs/page-010.jpg Why Do Robots Keep Repeating Sense, Think, Act? Robots keep repeating sense, think, act, because the world keeps changing! After each action, the robot senses again to see what changed. That loop lets it fix mistakes and handle https://socialmedia.xdme.com/tony/videos-book15/page-010.mp4 https://www.youtube.com/embed/00vZnZqWotE 110 2026-10-03T19:32:02+00:00 yes https://xdme.com/watch-book15-q011.html https://xdme.com/book15-thumbs/page-011.jpg Why Can a Robot Do the Same Job Thousands of Times Without Getting Tired? A robot can do the same job thousands of times because motors do not get tired! They do not get sore, bored, or sleepy. Doing one job over and over is where robots are strongest. https://socialmedia.xdme.com/tony/videos-book15/page-011.mp4 https://www.youtube.com/embed/vmj_Z31Wnm4 115 2026-10-03T19:40:05+00:00 yes https://xdme.com/watch-book15-q012.html https://xdme.com/book15-thumbs/page-012.jpg Why Are Some Easy Things for People Really Hard for Robots? Some easy things for people are really hard for robots! Picking up an egg uses lots of senses and tiny adjustments that your brain does without thinking. A robot has to be told eve https://socialmedia.xdme.com/tony/videos-book15/page-012.mp4 https://www.youtube.com/embed/d4lAbN23WwA 114 2026-10-03T19:47:38+00:00 yes https://xdme.com/watch-book15-q013.html https://xdme.com/book15-thumbs/page-013.jpg Why Does a Robot's Weight Matter So Much to Designers? A robot's weight matters because heavy robots need bigger motors, and bigger motors need bigger batteries! And those batteries are heavy too. So designers try to keep robots light https://socialmedia.xdme.com/tony/videos-book15/page-013.mp4 https://www.youtube.com/embed/Og0Nx-bxUT0 114 2026-10-03T19:56:13+00:00 yes https://xdme.com/watch-book15-q014.html https://xdme.com/book15-thumbs/page-014.jpg Why Isn't a Laptop a Robot? A laptop is not a robot because it cannot move around or change the physical world on its own! It can sense keys and show results on a screen. But a robot has a body that moves par https://socialmedia.xdme.com/tony/videos-book15/page-014.mp4 https://www.youtube.com/embed/9MmbcD2qc_c 107 2026-10-03T20:03:44+00:00 yes https://xdme.com/watch-book15-q015.html https://xdme.com/book15-thumbs/page-015.jpg Why Was the First Factory Robot Just an Arm? The first factory robot was just an arm because an arm could do a useful job right away! It was called Unimate, and it started work in 1961. It lifted hot, heavy metal parts, which https://socialmedia.xdme.com/tony/videos-book15/page-015.mp4 https://www.youtube.com/embed/ss_FiROjK1Y 111 2026-10-03T22:03:53+00:00 yes https://xdme.com/watch-book15-q016.html https://xdme.com/book15-thumbs/page-016.jpg Why Aren't Real Robots as Clever as Robots in Movies? Real robots are not as clever as movie robots, because movies are made for fun! Movie robots talk, walk, and understand everything. Real robots usually do one kind of job and need https://socialmedia.xdme.com/tony/videos-book15/page-016.mp4 https://www.youtube.com/embed/lcKy0jPgx5I 116 2026-10-04T02:24:42+00:00 yes https://xdme.com/watch-book15-q017.html https://xdme.com/book15-thumbs/page-017.jpg Why Do Engineers Draw a Robot Before They Build It? Engineers draw a robot before building it, because drawing is cheaper and faster! Changing a drawing takes seconds, with just an eraser. Changing a finished robot can take days, an https://socialmedia.xdme.com/tony/videos-book15/page-017.mp4 https://www.youtube.com/embed/T7LzWkXpFcY 113 2026-10-04T02:27:46+00:00 yes https://xdme.com/watch-book15-q018.html https://xdme.com/book15-thumbs/page-018.jpg Why Do Engineers Test a Robot Again and Again? Engineers test a robot again and again, because problems often show up only some of the time! A wheel might slip on a shiny floor, or a sensor might fail in sunlight. Testing finds https://socialmedia.xdme.com/tony/videos-book15/page-018.mp4 https://www.youtube.com/embed/qDTXVggaUUk 113 2026-10-04T02:32:48+00:00 yes https://xdme.com/watch-book15-q019.html https://xdme.com/book15-thumbs/page-019.jpg Why Do Robots Have Emergency Stop Buttons? Robots have emergency stop buttons so anyone can stop them fast if something goes wrong! The button is called an e-stop, short for emergency stop. It cuts power so the robot stops https://socialmedia.xdme.com/tony/videos-book15/page-019.mp4 https://www.youtube.com/embed/Eu6vk8-lww8 116 2026-10-04T02:36:19+00:00 yes https://xdme.com/watch-book15-q020.html https://xdme.com/book15-thumbs/page-020.jpg Why Are Some Big Robots Kept Behind Safety Fences? Big factory robots are kept behind safety fences because their arms swing fast and with strong force! The fence keeps people at a safe distance while the robot works. A robot does https://socialmedia.xdme.com/tony/videos-book15/page-020.mp4 https://www.youtube.com/embed/Zs0jYhX7ax8 114 2026-10-04T02:40:23+00:00 yes https://xdme.com/watch-book15-q021.html https://xdme.com/book15-thumbs/page-021.jpg Why Can Some Robots Work Safely Next to People? Some robots can work safely next to people because they are designed to share space! They are called collaborative robots, or cobots. Careful design makes sharing possible, and it https://socialmedia.xdme.com/tony/videos-book15/page-021.mp4 https://www.youtube.com/embed/CELDqmYOAYw 116 2026-10-04T02:43:25+00:00 yes https://xdme.com/watch-book15-q022.html https://xdme.com/book15-thumbs/page-022.jpg What Does It Mean When a Robot Is Autonomous? An autonomous robot makes its own decisions about how to do its job! Autonomous means able to run by itself. It uses its sensors and its program, and it does not need someone to st https://socialmedia.xdme.com/tony/videos-book15/page-022.mp4 https://www.youtube.com/embed/iXj0mDn0MVs 114 2026-10-04T02:46:57+00:00 yes https://xdme.com/watch-book15-q023.html https://xdme.com/book15-thumbs/page-023.jpg Why Do Some Robots Need a Person to Steer Them From Far Away? Some robots are steered by a person far away, because some jobs are too tricky or risky for a program alone! This is called teleoperation, which means working from a distance. A pe https://socialmedia.xdme.com/tony/videos-book15/page-023.mp4 https://www.youtube.com/embed/aEKiyb4XaKI 116 2026-10-04T02:49:59+00:00 yes https://xdme.com/watch-book15-q024.html https://xdme.com/book15-thumbs/page-024.jpg Why Do Engineers Send Robots to Places That Are Too Hot, Too Deep, or Too Far for People? Engineers send robots to places that are too hot, too deep, or too far for people! Robots do not need air, food, or comfortable temperatures. They can go first, so people can learn https://socialmedia.xdme.com/tony/videos-book15/page-024.mp4 https://www.youtube.com/embed/m_NZcC7h40M 117 2026-10-04T02:53:32+00:00 yes https://xdme.com/watch-book15-q025.html https://xdme.com/book15-thumbs/page-025.jpg How Small Can a Robot Get, and How Big? Robots can be super tiny or really huge, and size depends on the job! Scientists have built flying robots smaller than a coin. Others are smaller than a grain of rice, and some are https://socialmedia.xdme.com/tony/videos-book15/page-025.mp4 https://www.youtube.com/embed/R-7WburQPVc 110 2026-10-04T02:56:33+00:00 yes https://xdme.com/watch-book15-q026.html https://xdme.com/book15-thumbs/page-026.jpg What Is a Sensor, and Why Do Robots Need Them? A sensor is a part that measures something in the world and turns it into a signal! That signal is usually a number that the robot's brain can use. Without sensors, a robot would b https://socialmedia.xdme.com/tony/videos-book15/page-026.mp4 https://www.youtube.com/embed/nuUwCqe4YIs 114 2026-10-04T03:00:05+00:00 yes https://xdme.com/watch-book15-q027.html https://xdme.com/book15-thumbs/page-027.jpg How Does a Bump Sensor Tell a Robot It Has Hit a Wall? A bump sensor tells a robot it hit a wall by closing a tiny switch! When the robot bumps something, the switch is pushed. Then electricity can flow, and the brain gets a signal. https://socialmedia.xdme.com/tony/videos-book15/page-027.mp4 https://www.youtube.com/embed/93AJt_3E9io 108 2026-10-04T03:03:07+00:00 yes https://xdme.com/watch-book15-q028.html https://xdme.com/book15-thumbs/page-028.jpg How Does a Robot’s Ultrasonic Sensor Find How Far Away a Wall Is? An ultrasonic sensor finds how far away a wall is by sending out sound and listening for the echo! The sound is too high-pitched for us to hear. The longer the echo takes, the fart https://socialmedia.xdme.com/tony/videos-book15/page-028.mp4 https://www.youtube.com/embed/RW-a_rsONGk 114 2026-10-04T03:06:09+00:00 yes https://xdme.com/watch-book15-q029.html https://xdme.com/book15-thumbs/page-029.jpg How Does a Robot Use a Laser Beam to Map the Space Around It? A lidar sensor uses laser light to map the space around a robot! It spins around and sends out thousands of short, safe laser pulses every second. Each pulse is timed as it bounces https://socialmedia.xdme.com/tony/videos-book15/page-029.mp4 https://www.youtube.com/embed/UcUqXXk4ZJA 112 2026-10-04T03:13:41+00:00 yes https://xdme.com/watch-book15-q030.html https://xdme.com/book15-thumbs/page-030.jpg Why Can a Robot Follow a Black Line on the Floor? A robot can follow a black line because black soaks up light and white bounces it back! A sensor underneath shines a little light on the floor. It measures how much light comes bac https://socialmedia.xdme.com/tony/videos-book15/page-030.mp4 https://www.youtube.com/embed/j9SBlT666XI 107 2026-10-04T03:16:43+00:00 yes https://xdme.com/watch-book15-q031.html https://xdme.com/book15-thumbs/page-031.jpg How Does a Robot Know Which Way Is Up? A robot knows which way is up with two tiny parts, an accelerometer and a gyroscope! One feels the pull of gravity, and the other feels turning. Together they tell the robot how it https://socialmedia.xdme.com/tony/videos-book15/page-031.mp4 https://www.youtube.com/embed/oR-Q-G_ZAyM 115 2026-10-04T03:20:46+00:00 yes https://xdme.com/watch-book15-q032.html https://xdme.com/book15-thumbs/page-032.jpg How Does a Robot Know How Far It Has Driven? A robot knows how far it has driven by counting how much its wheels turn! A part called an encoder counts the turns. Then it multiplies the turns by the distance around the wheel. https://socialmedia.xdme.com/tony/videos-book15/page-032.mp4 https://www.youtube.com/embed/ftKdnrh_fik 112 2026-10-04T03:32:54+00:00 yes https://xdme.com/watch-book15-q033.html https://xdme.com/book15-thumbs/page-033.jpg Why Do Some Robots Have Touch-Sensitive Skin? Some robots have touch-sensitive skin so they know where they are touched and how hard! The skin is a layer with many tiny pressure sensors. It helps robots be gentle and safe, jus https://socialmedia.xdme.com/tony/videos-book15/page-033.mp4 https://www.youtube.com/embed/4-70GkrKJD8 111 2026-10-04T03:47:55+00:00 yes https://xdme.com/watch-book15-q034.html https://xdme.com/book15-thumbs/page-034.jpg How Can a Robot Use a Camera to Find a Ball? A robot can use a camera to find a ball by looking for patches of the ball's color! A camera takes a picture made of many tiny dots called pixels. Each pixel is stored as a number https://socialmedia.xdme.com/tony/videos-book15/page-034.mp4 https://www.youtube.com/embed/382MubmZHaY 105 2026-10-04T04:01:33+00:00 yes https://xdme.com/watch-book15-q035.html https://xdme.com/book15-thumbs/page-035.jpg Why Do Robots Sometimes Get Confused by Bright Sunlight? Robots can get confused by bright sunlight because many robot sensors measure light! Very bright sunlight can overload them, like a flash in your face. Then the sensor cannot tell https://socialmedia.xdme.com/tony/videos-book15/page-035.mp4 https://www.youtube.com/embed/Q_63c4Nep5g 116 2026-10-04T04:14:35+00:00 yes https://xdme.com/watch-book15-q036.html https://xdme.com/book15-thumbs/page-036.jpg Why Do Robots Use Many Sensors Instead of Just One? Robots use many sensors because every sensor has weak spots! By combining several sensors, the robot can check one against another. That makes its picture of the world more reliabl https://socialmedia.xdme.com/tony/videos-book15/page-036.mp4 https://www.youtube.com/embed/BlWZFJ5XZ6o 114 2026-10-04T04:22:39+00:00 yes https://xdme.com/watch-book15-q037.html https://xdme.com/book15-thumbs/page-037.jpg How Does a Robot Sense Heat? A robot can sense heat in two main ways! Some sensors change how easily electricity flows when they warm up. Others catch infrared light, which warm things give off. https://socialmedia.xdme.com/tony/videos-book15/page-037.mp4 https://www.youtube.com/embed/4ARZgRGGwhY 115 2026-10-04T04:30:11+00:00 yes https://xdme.com/watch-book15-q038.html https://xdme.com/book15-thumbs/page-038.jpg Why Can a Robot Turn Toward a Clap? A robot can turn toward a clap because it uses two or more microphones! The sound reaches the closer microphone a tiny bit sooner. It is also a bit louder there. https://socialmedia.xdme.com/tony/videos-book15/page-038.mp4 https://www.youtube.com/embed/0D3WsMnII0s 110 2026-10-04T04:37:42+00:00 yes https://xdme.com/watch-book15-q039.html https://xdme.com/book15-thumbs/page-039.jpg Why Does a Robot with a Light Sensor Follow a Flashlight? A robot with light sensors follows a flashlight by comparing left and right! It has one sensor on the left and one on the right. A simple rule makes it look like it is chasing the https://socialmedia.xdme.com/tony/videos-book15/page-039.mp4 https://www.youtube.com/embed/lax4gAPh3Bc 107 2026-10-04T04:45:16+00:00 yes https://xdme.com/watch-book15-q040.html https://xdme.com/book15-thumbs/page-040.jpg Why Do Robots Use GPS Outdoors but Not Inside? Robots use GPS outdoors because it listens to signals from satellites high above Earth! The signals are very weak, since they travel a long way. Walls and roofs block or weaken the https://socialmedia.xdme.com/tony/videos-book15/page-040.mp4 https://www.youtube.com/embed/Nf9JRD5nUPg 120 2026-10-04T04:53:18+00:00 yes https://xdme.com/watch-book15-q041.html https://xdme.com/book15-thumbs/page-041.jpg Why Doesn't a Robot Vacuum Fall Down the Stairs? A robot vacuum does not fall down the stairs because it has cliff sensors! They shine infrared light at the floor and check for the light that bounces back. At a stair edge, almost https://socialmedia.xdme.com/tony/videos-book15/page-041.mp4 https://www.youtube.com/embed/QWJAxvubo5g 115 2026-10-04T05:00:50+00:00 yes https://xdme.com/watch-book15-q042.html https://xdme.com/book15-thumbs/page-042.jpg Why Do Robot Sensors Sometimes Get Things Wrong? Robot sensors sometimes get things wrong because the real world is messy! Dust, glare, noise, and shiny, clear, or soft surfaces can fool them. Even the best sensors are never perf https://socialmedia.xdme.com/tony/videos-book15/page-042.mp4 https://www.youtube.com/embed/jHU8pdyDBuQ 112 2026-10-04T05:08:52+00:00 yes https://xdme.com/watch-book15-q043.html https://xdme.com/book15-thumbs/page-043.jpg Why Do Automatic Doors Open as You Walk Up? Automatic doors open as you walk up because a sensor notices you! It sits above the door and watches the space in front. When something moves in, it tells the motor to open. https://socialmedia.xdme.com/tony/videos-book15/page-043.mp4 https://www.youtube.com/embed/m2caJ3LUMNQ 110 2026-10-04T05:16:24+00:00 yes https://xdme.com/watch-book15-q044.html https://xdme.com/book15-thumbs/page-044.jpg How Does a Robot Arm Know When It Has Reached the End of Its Swing? A robot arm knows where its end is by counting turns in its motor! Some arms also have limit switches at the ends of the swing. Counting and switches work together to keep the arm https://socialmedia.xdme.com/tony/videos-book15/page-044.mp4 https://www.youtube.com/embed/JT4C3cUmeCk 108 2026-10-04T05:23:56+00:00 yes https://xdme.com/watch-book15-q045.html https://xdme.com/book15-thumbs/page-045.jpg How Can a Magnet Tell a Robot Where Its Parts Are? A magnet can tell a robot where its parts are, with a sensor that feels magnetism! The sensor is called a Hall sensor. A small magnet goes on the moving part, and the sensor stays https://socialmedia.xdme.com/tony/videos-book15/page-045.mp4 https://www.youtube.com/embed/ziQIY7Rc_pQ 108 2026-10-04T05:31:27+00:00 yes https://xdme.com/watch-book15-q046.html https://xdme.com/book15-thumbs/page-046.jpg How Does a Robot Hand Know How Hard to Squeeze? A robot hand knows how hard to squeeze by using feedback! Some fingers have pressure sensors, and the motor reports how hard it is working. The brain stops closing when it reaches https://socialmedia.xdme.com/tony/videos-book15/page-046.mp4 https://www.youtube.com/embed/Z1XtWjaudvI 108 2026-10-04T05:38:59+00:00 yes https://xdme.com/watch-book15-q047.html https://xdme.com/book15-thumbs/page-047.jpg How Does a Light Curtain Stop a Factory Robot When Someone Gets Close? A light curtain stops a factory robot by using a row of invisible light beams! A sensor on the other side checks that each beam arrives. If a hand breaks a beam, the robot is told https://socialmedia.xdme.com/tony/videos-book15/page-047.mp4 https://www.youtube.com/embed/0r9EUpzme50 111 2026-10-04T05:46:30+00:00 yes https://xdme.com/watch-book15-q048.html https://xdme.com/book15-thumbs/page-048.jpg How Can a Robot Sort Red Blocks From Blue Ones? A robot can sort red blocks from blue ones by measuring the color of light that comes back! A color sensor or a camera does the measuring. Then a program compares the numbers with https://socialmedia.xdme.com/tony/videos-book15/page-048.mp4 https://www.youtube.com/embed/inSFlbRkn0o 109 2026-10-04T05:54:03+00:00 yes https://xdme.com/watch-book15-q049.html https://xdme.com/book15-thumbs/page-049.jpg Why Do Some Robots Carry Gas Sensors? Some robots carry gas sensors because they can notice air that is unsafe for people! A gas sensor reacts to certain gases, like smoke or harmful fumes. It can notice things our nos https://socialmedia.xdme.com/tony/videos-book15/page-049.mp4 https://www.youtube.com/embed/msEg1ADcCew 112 2026-10-04T06:02:06+00:00 yes https://xdme.com/watch-book15-q050.html https://xdme.com/book15-thumbs/page-050.jpg How Does a Robot Find Its Charging Station? A robot vacuum finds its charging station by following a signal from the dock! The dock sends out an invisible beam of infrared light. When the battery is low, the robot looks for https://socialmedia.xdme.com/tony/videos-book15/page-050.mp4 https://www.youtube.com/embed/c96QBH1NbWA 111 2026-10-04T06:09:38+00:00 yes https://xdme.com/watch-book15-q051.html https://xdme.com/book15-thumbs/page-051.jpg Why Does a Motor Spin When You Connect a Battery? A motor spins because electricity can turn a coil of wire into a magnet! Other magnets nearby push and pull on it, and that makes the coil turn. Almost every robot uses electric mo https://socialmedia.xdme.com/tony/videos-book15/page-051.mp4 https://www.youtube.com/embed/LtP3UYN3HiY 116 2026-10-04T06:17:11+00:00 yes https://xdme.com/watch-book15-q052.html https://xdme.com/book15-thumbs/page-052.jpg Why Do Robot Motors Have Tiny Gearboxes? A small motor spins very fast, but it has very little turning power! A tiny gearbox trades speed for strength. That is how a small motor can help a robot lift something heavy. https://socialmedia.xdme.com/tony/videos-book15/page-052.mp4 https://www.youtube.com/embed/nYbQ9z6nbg0 114 2026-10-04T06:25:15+00:00 yes https://xdme.com/watch-book15-q053.html https://xdme.com/book15-thumbs/page-053.jpg What Is a Servo Motor? A servo motor is a motor with its own helper brain! You tell it an angle, and it turns there and holds still. Servos move robot arms and legs to exact angles. https://socialmedia.xdme.com/tony/videos-book15/page-053.mp4 https://www.youtube.com/embed/ELSpqx3dUiw 113 2026-10-04T06:32:48+00:00 yes https://xdme.com/watch-book15-q054.html https://xdme.com/book15-thumbs/page-054.jpg Why Can a Stepper Motor Move in Tiny, Exact Steps? A stepper motor turns in tiny, exact steps! Each electrical pulse turns it by one small step, like 1.8 degrees. Because the steps are exact, a robot can simply count them. 3D print https://socialmedia.xdme.com/tony/videos-book15/page-054.mp4 https://www.youtube.com/embed/1UORvBX19cU 123 2026-10-04T06:40:50+00:00 yes https://xdme.com/watch-book15-q055.html https://xdme.com/book15-thumbs/page-055.jpg Why Do Robots Use Wheels More Often than Legs? Wheels are simple, quick, and save energy on flat ground! Legs are more complicated, but they can step over rocks and climb stairs. The best choice depends on where the robot will https://socialmedia.xdme.com/tony/videos-book15/page-055.mp4 https://www.youtube.com/embed/PpNMrnne2lk 114 2026-10-04T06:48:22+00:00 yes https://xdme.com/watch-book15-q056.html https://xdme.com/book15-thumbs/page-056.jpg Why Do Many Walking Robots Have Four Legs? Four legs make a robot steady, because three feet can stay on the ground while one steps! Two-legged walking is much harder to balance. Four legs also spread out the weight and can https://socialmedia.xdme.com/tony/videos-book15/page-056.mp4 https://www.youtube.com/embed/GQAogRVwpxQ 115 2026-10-04T06:55:54+00:00 yes https://xdme.com/watch-book15-q057.html https://xdme.com/book15-thumbs/page-057.jpg Why Is Balancing on Two Legs Such a Challenge for a Robot? Balancing on two legs is hard because the robot's weight must stay over a tiny spot! That spot is where its feet touch the ground. If the weight drifts outside it, the robot tips o https://socialmedia.xdme.com/tony/videos-book15/page-057.mp4 https://www.youtube.com/embed/ip9d4nS4rk8 112 2026-10-04T07:03:27+00:00 yes https://xdme.com/watch-book15-q058.html https://xdme.com/book15-thumbs/page-058.jpg How Does a Robot Turn by Spinning Its Wheels at Different Speeds? A two-wheeled robot turns by spinning its wheels at different speeds! No steering wheel is needed. The faster side pushes the robot around toward the slower side. https://socialmedia.xdme.com/tony/videos-book15/page-058.mp4 https://www.youtube.com/embed/h-zaDXD-k_I 108 2026-10-04T07:11:00+00:00 yes https://xdme.com/watch-book15-q059.html https://xdme.com/book15-thumbs/page-059.jpg Why Do Some Robots Have Tank Treads? Tank treads are belts that go around the wheels! They spread the robot's weight over a large area, so it does not sink into soft ground. They also grip rough ground. https://socialmedia.xdme.com/tony/videos-book15/page-059.mp4 https://www.youtube.com/embed/tt_FXuVfRW0 110 2026-10-04T07:18:32+00:00 yes https://xdme.com/watch-book15-q060.html https://xdme.com/book15-thumbs/page-060.jpg Why Do Some Robots Roll on Balls or Special Sideways Wheels? Some robots can move sideways without turning, thanks to special wheels! Others balance and roll on a ball. These designs help in tight spaces, like warehouses. https://socialmedia.xdme.com/tony/videos-book15/page-060.mp4 https://www.youtube.com/embed/UdG0l_QmT3U 114 2026-10-04T07:26:05+00:00 yes https://xdme.com/watch-book15-q061.html https://xdme.com/book15-thumbs/page-061.jpg Why Do Robot Arms Have Joints Like a Shoulder and an Elbow? Joints let parts of a robot arm bend and turn, just like your shoulder, elbow, and wrist! Each joint adds one more way for the arm to move. More joints reach more places. https://socialmedia.xdme.com/tony/videos-book15/page-061.mp4 https://www.youtube.com/embed/FXcjEB2RCQY 109 2026-10-04T07:33:45+00:00 yes https://xdme.com/watch-book15-q062.html https://xdme.com/book15-thumbs/page-062.jpg Why Does a Robot Arm Need About Six Joints to Reach Anywhere? To put a robot hand in any spot, at any angle, an arm needs about six joints! Three joints set the position, and three more set the direction. Engineers call this six degrees of fr https://socialmedia.xdme.com/tony/videos-book15/page-062.mp4 https://www.youtube.com/embed/Li2_ndSxtfs 114 2026-10-04T07:41:17+00:00 yes https://xdme.com/watch-book15-q063.html https://xdme.com/book15-thumbs/page-063.jpg How Does a Robot Gripper Pick Up Things? A robot gripper is like a hand with two or three fingers that close together! A motor pulls the fingers closed, and rubber pads help them grip. Different jobs use different gripper https://socialmedia.xdme.com/tony/videos-book15/page-063.mp4 https://www.youtube.com/embed/IUav1VS_4xo 112 2026-10-04T07:48:50+00:00 yes https://xdme.com/watch-book15-q064.html https://xdme.com/book15-thumbs/page-064.jpg Why Do Some Robot Hands Use Suction Cups? A suction cup holds on because air outside pushes it against the surface! A robot pump pulls the air out of the cup. Then the air around us does the holding. https://socialmedia.xdme.com/tony/videos-book15/page-064.mp4 https://www.youtube.com/embed/aQF2LoCeVmY 110 2026-10-04T07:56:22+00:00 yes https://xdme.com/watch-book15-q065.html https://xdme.com/book15-thumbs/page-065.jpg Why Are Some Robots Soft and Squishy? A soft robot is made of bendy material, like silicone rubber! Air or liquid fills little hollow chambers and makes the fingers curl. Being soft makes them gentle with delicate thin https://socialmedia.xdme.com/tony/videos-book15/page-065.mp4 https://www.youtube.com/embed/QYWqmHS2uFk 113 2026-10-04T08:03:55+00:00 yes https://xdme.com/watch-book15-q066.html https://xdme.com/book15-thumbs/page-066.jpg Why Does a Long Robot Arm Lift Less than a Short One? A long robot arm lifts less because it acts like a lever! The farther a weight is from the shoulder, the more twisting force the motor must make to hold it up. A short arm needs mu https://socialmedia.xdme.com/tony/videos-book15/page-066.mp4 https://www.youtube.com/embed/c77DRp5x6w8 110 2026-10-04T08:11:28+00:00 yes https://xdme.com/watch-book15-q067.html https://xdme.com/book15-thumbs/page-067.jpg Why Do Robots Use Belts and Pulleys? A belt and pulleys pass turning from one wheel to another! Unlike gears, they can connect parts that are far apart. They are light, quiet, and a bit flexible. https://socialmedia.xdme.com/tony/videos-book15/page-067.mp4 https://www.youtube.com/embed/NG6GSYqfC6o 108 2026-10-04T08:19:00+00:00 yes https://xdme.com/watch-book15-q068.html https://xdme.com/book15-thumbs/page-068.jpg Why Do Robot Motors Get Warm? Robot motors get warm because some electricity turns into heat! Wires push back on the electricity, and moving parts rub together. A warm motor means a hard-working motor. https://socialmedia.xdme.com/tony/videos-book15/page-068.mp4 https://www.youtube.com/embed/G2Vo4zrvVEM 114 2026-10-04T08:26:34+00:00 yes https://xdme.com/watch-book15-q069.html https://xdme.com/book15-thumbs/page-069.jpg How Does a Robot Arm Know Exactly Where Its Hand Is? A robot arm knows where its hand is by measuring every joint angle! Then it adds up those angles and the arm lengths, using some math. It does not even need a camera. https://socialmedia.xdme.com/tony/videos-book15/page-069.mp4 https://www.youtube.com/embed/rXE1tcRrXVw 109 2026-10-04T08:34:06+00:00 yes https://xdme.com/watch-book15-q070.html https://xdme.com/book15-thumbs/page-070.jpg Why Does a Robot Sometimes Overshoot Its Stop and Wobble Back? A robot overshoots because moving things keep moving! This is called inertia. The robot slides past its target, notices, and wiggles back. https://socialmedia.xdme.com/tony/videos-book15/page-070.mp4 https://www.youtube.com/embed/PorHrT0qDXE 116 2026-10-04T08:41:38+00:00 yes https://xdme.com/watch-book15-q071.html https://xdme.com/book15-thumbs/page-071.jpg How Can a Robot Jump or Hop? A jumping robot stores energy in a spring, then lets it go all at once! A motor squeezes the spring slowly, and a latch releases it in an instant. The robot springs into the air. https://socialmedia.xdme.com/tony/videos-book15/page-071.mp4 https://www.youtube.com/embed/nOV1k2VRx60 112 2026-10-04T08:49:11+00:00 yes https://xdme.com/watch-book15-q072.html https://xdme.com/book15-thumbs/page-072.jpg Why Do Some Robots Wriggle Like Snakes? Snake robots wriggle because they bend in a wave that travels down their body! The wave pushes against the ground or walls and moves them forward. Their long, thin bodies fit where https://socialmedia.xdme.com/tony/videos-book15/page-072.mp4 https://www.youtube.com/embed/tu9Mv3ih8I0 110 2026-10-04T08:56:44+00:00 yes https://xdme.com/watch-book15-q073.html https://xdme.com/book15-thumbs/page-073.jpg How Can a Robot Balance on Just Two Wheels? A two-wheeled robot balances like a broom on your hand! When it starts to tip, its wheels roll under it to catch it. It looks calm, but it is always catching itself. https://socialmedia.xdme.com/tony/videos-book15/page-073.mp4 https://www.youtube.com/embed/t_wwLrFAj_U 108 2026-10-04T09:04:18+00:00 yes https://xdme.com/watch-book15-q074.html https://xdme.com/book15-thumbs/page-074.jpg Why Do Some Strong Robots Push with Air or Liquid? Some strong robots use air or liquid under pressure to push a piston! Air makes quick, springy moves, and liquid makes strong, steady ones. These are great when a job needs a lot o https://socialmedia.xdme.com/tony/videos-book15/page-074.mp4 https://www.youtube.com/embed/ApkQEjeXRMI 113 2026-10-04T09:11:51+00:00 yes https://xdme.com/watch-book15-q075.html https://xdme.com/book15-thumbs/page-075.jpg Why Do Robot Builders Choose Lightweight Materials? Builders choose lightweight materials because heavy parts take more energy to move and stop! A lighter robot needs smaller motors and batteries. And it can work longer. https://socialmedia.xdme.com/tony/videos-book15/page-075.mp4 https://www.youtube.com/embed/QszTg4vy9G4 117 2026-10-04T09:19:27+00:00 yes https://xdme.com/watch-book15-q076.html https://xdme.com/book15-thumbs/page-076.jpg How Does a Robot Vacuum Map a Room? A robot vacuum draws a map of your room as it drives around! It measures distances to walls and furniture, and counts its wheel turns. Then it cleans the floor in neat lines. https://socialmedia.xdme.com/tony/videos-book15/page-076.mp4 https://www.youtube.com/embed/Wr4R6RXiCfM 116 2026-10-03T19:10:43+00:00 yes https://xdme.com/watch-book15-q077.html https://xdme.com/book15-thumbs/page-077.jpg Why Do Robot Vacuums Get Stuck on Socks and Cords? A robot vacuum sees the room as a thin flat layer of obstacles at one height! A thin cord or a flat sock may be too low or too thin to notice. Then it drives over them and gets tan https://socialmedia.xdme.com/tony/videos-book15/page-077.mp4 https://www.youtube.com/embed/0kJ-1jzmycs 109 2026-10-03T19:10:45+00:00 yes https://xdme.com/watch-book15-q078.html https://xdme.com/book15-thumbs/page-078.jpg Why Does a Robot Lawn Mower Stay Inside the Yard? A robot lawn mower stays in the yard by sensing an invisible boundary! Usually a thin wire is buried at the edge of the lawn. The wire carries a weak signal that the mower can feel https://socialmedia.xdme.com/tony/videos-book15/page-078.mp4 https://www.youtube.com/embed/HQubkiMQsd0 112 2026-10-03T19:10:46+00:00 yes https://xdme.com/watch-book15-q079.html https://xdme.com/book15-thumbs/page-079.jpg How Do Pool-Cleaning Robots Clean Underwater? A pool robot cleans by pulling water through a filter bag as it drives! It scrubs with brushes and its filter catches the dirt. It follows a pattern across the floor and the walls. https://socialmedia.xdme.com/tony/videos-book15/page-079.mp4 https://www.youtube.com/embed/s8h_XgCSQPM 112 2026-10-03T19:10:48+00:00 yes https://xdme.com/watch-book15-q080.html https://xdme.com/book15-thumbs/page-080.jpg How Do Window-Cleaning Robots Stick to Glass? A window-cleaning robot sticks to glass using suction! A fan or pump pulls air out from under it. Then the air outside pushes the robot against the window. https://socialmedia.xdme.com/tony/videos-book15/page-080.mp4 https://www.youtube.com/embed/WPZF_0z0kbI 105 2026-10-03T19:11:41+00:00 yes https://xdme.com/watch-book15-q081.html https://xdme.com/book15-thumbs/page-081.jpg Why Do Warehouses Use Flat Robots That Carry Shelves? In some warehouses, flat robots slide under a tall shelf, lift it, and carry it to a worker! The shelves come to the people, instead of people walking the aisles. That saves time a https://socialmedia.xdme.com/tony/videos-book15/page-081.mp4 https://www.youtube.com/embed/nB79wwpGQms 111 2026-10-03T19:14:43+00:00 yes https://xdme.com/watch-book15-q082.html https://xdme.com/book15-thumbs/page-082.jpg How Do Factory Robots Paint Cars So Evenly? A painting robot repeats the exact same path, at the same speed, every time! That gives each part of the car the same amount of paint. The paint lands in a smooth, even layer. https://socialmedia.xdme.com/tony/videos-book15/page-082.mp4 https://www.youtube.com/embed/sMkqpHUKgPw 109 2026-10-03T19:17:52+00:00 yes https://xdme.com/watch-book15-q083.html https://xdme.com/book15-thumbs/page-083.jpg How Can a Robot Pick a Strawberry Without Squishing It? A strawberry-picking robot finds ripe berries by color, then picks them gently! A camera spots the red berries. A soft gripper or small cutter reaches the stem, so the berry isn't https://socialmedia.xdme.com/tony/videos-book15/page-083.mp4 https://www.youtube.com/embed/Hi79fvLae7Y 112 2026-10-03T19:20:24+00:00 yes https://xdme.com/watch-book15-q084.html https://xdme.com/book15-thumbs/page-084.jpg Why Do Farm Robots Drive Along the Crop Rows? Farm robots drive along crop rows to avoid stepping on the plants! They use GPS and cameras to follow very straight lines. Staying in the lines protects the crops. https://socialmedia.xdme.com/tony/videos-book15/page-084.mp4 https://www.youtube.com/embed/Fgopnc-rXtA 114 2026-10-03T19:23:58+00:00 yes https://xdme.com/watch-book15-q085.html https://xdme.com/book15-thumbs/page-085.jpg How Do Robots Sort Recycling? Robots sort recycling by looking at each item as it rides past on a conveyor belt! Cameras and sensors tell the items apart. A robot arm or a puff of air puts each one in the right https://socialmedia.xdme.com/tony/videos-book15/page-085.mp4 https://www.youtube.com/embed/2ZLxSHgNsO4 114 2026-10-03T19:31:31+00:00 yes https://xdme.com/watch-book15-q086.html https://xdme.com/book15-thumbs/page-086.jpg What Is Canadarm2, and What Does It Do? Canadarm2 is a huge robotic arm on the International Space Station, built in Canada! It is about 17.6 meters long, and it has seven joints. Astronauts use it to catch spacecraft an https://socialmedia.xdme.com/tony/videos-book15/page-086.mp4 https://www.youtube.com/embed/npXAVO0qRpM 122 2026-10-03T19:39:33+00:00 yes https://xdme.com/watch-book15-q087.html https://xdme.com/book15-thumbs/page-087.jpg How Do Small Robots Crawl Through Pipes to Find Leaks? Pipe robots are small rolling machines with a camera and a light! They travel through pipes to look for cracks, blockages, and leaks. They send pictures back to a person, so no one https://socialmedia.xdme.com/tony/videos-book15/page-087.mp4 https://www.youtube.com/embed/s7V_2K7SG6U 112 2026-10-03T19:47:40+00:00 yes https://xdme.com/watch-book15-q088.html https://xdme.com/book15-thumbs/page-088.jpg Why Do Robots Climb Wind Turbines and Tall Towers? Robots climb wind turbines and towers to check them for cracks and damage! The blades are very tall, so checking them is hard work. Robots mean fewer risky climbs for people. https://socialmedia.xdme.com/tony/videos-book15/page-088.mp4 https://www.youtube.com/embed/s8oqR2YZdmA 115 2026-10-03T19:55:42+00:00 yes https://xdme.com/watch-book15-q089.html https://xdme.com/book15-thumbs/page-089.jpg Why Do Delivery Robots Roll Along Sidewalks? Delivery robots are small, wheeled boxes that roll along sidewalks at walking speed! They use cameras, lidar, and GPS to follow a route. They are designed to be slow and careful. https://socialmedia.xdme.com/tony/videos-book15/page-089.mp4 https://www.youtube.com/embed/ySW-53u7iLs 113 2026-10-03T20:03:48+00:00 yes https://xdme.com/watch-book15-q090.html https://xdme.com/book15-thumbs/page-090.jpg How Can Small Robots Help Search a Collapsed Building? Small, bendy robots can crawl into narrow gaps after a building has fallen down! They carry cameras, lights, and microphones. They help rescue teams see where it is safe to dig. https://socialmedia.xdme.com/tony/videos-book15/page-090.mp4 https://www.youtube.com/embed/DMdJEuJcX5k 113 2026-10-03T22:03:55+00:00 yes https://xdme.com/watch-book15-q091.html https://xdme.com/book15-thumbs/page-091.jpg How Do Robots Scrub the Bottoms of Big Ships? Robots scrub ship bottoms to remove tiny sea animals like barnacles! A clean hull glides through the water more smoothly. That saves fuel and protects the sea. https://socialmedia.xdme.com/tony/videos-book15/page-091.mp4 https://www.youtube.com/embed/Z4cKlOWU7YI 114 2026-10-04T02:24:44+00:00 yes https://xdme.com/watch-book15-q092.html https://xdme.com/book15-thumbs/page-092.jpg How Can a Robot Build a Brick Wall? A brick-laying robot has a long arm that picks up a brick, adds glue, and sets it in an exact spot! It follows a plan that says where every brick goes. It can lay a brick every few https://socialmedia.xdme.com/tony/videos-book15/page-092.mp4 https://www.youtube.com/embed/IwqC_sRKorA 113 2026-10-04T02:27:47+00:00 yes https://xdme.com/watch-book15-q093.html https://xdme.com/book15-thumbs/page-093.jpg Why Do Robots in Science Labs Move Tiny Drops of Liquid? Lab robots move tiny drops of liquid because they can measure more exactly than hands! They use thin tubes to move the drops from one container to another. A drop can be smaller th https://socialmedia.xdme.com/tony/videos-book15/page-093.mp4 https://www.youtube.com/embed/o8zmIaEs238 112 2026-10-04T02:32:48+00:00 yes https://xdme.com/watch-book15-q094.html https://xdme.com/book15-thumbs/page-094.jpg Why Do Greenhouse Robots Check Plants One by One? Greenhouse robots check plants one by one so they can spot problems early! They roll or hang between the rows and use cameras to look at each plant. A small problem is easier to fi https://socialmedia.xdme.com/tony/videos-book15/page-094.mp4 https://www.youtube.com/embed/_Tpleywbhm4 113 2026-10-04T02:36:20+00:00 yes https://xdme.com/watch-book15-q095.html https://xdme.com/book15-thumbs/page-095.jpg Why Can Some Robots Work in Total Darkness? Some robots can work in total darkness because they make their own signals! They send out light, sound, or radio waves, and read the echoes. Touch sensors work in the dark, too. https://socialmedia.xdme.com/tony/videos-book15/page-095.mp4 https://www.youtube.com/embed/JEOfF2MO518 112 2026-10-04T02:40:24+00:00 yes https://xdme.com/watch-book15-q096.html https://xdme.com/book15-thumbs/page-096.jpg How Do Warehouse Robots Avoid Bumping Into Each Other? Warehouse robots avoid bumping by following traffic rules, like cars do! A central computer acts like a traffic controller and gives each robot a path. Each robot also has its own https://socialmedia.xdme.com/tony/videos-book15/page-096.mp4 https://www.youtube.com/embed/hVEh125h5rI 115 2026-10-04T02:43:26+00:00 yes https://xdme.com/watch-book15-q097.html https://xdme.com/book15-thumbs/page-097.jpg How Do Robots Pack Cookies Without Breaking Them? A cookie-packing robot handles each cookie slowly and softly! A camera spots where each cookie is. A soft gripper or a gentle suction pad picks it up without pressing too hard. https://socialmedia.xdme.com/tony/videos-book15/page-097.mp4 https://www.youtube.com/embed/wBcYUZfpbhE 112 2026-10-04T02:46:58+00:00 yes https://xdme.com/watch-book15-q098.html https://xdme.com/book15-thumbs/page-098.jpg Why Do Robots Clean Solar Panels? Dust and dirt on a solar panel block some sunlight, so the panel makes less electricity! Cleaning robots wipe the panels so more light gets through. More sunlight means more power. https://socialmedia.xdme.com/tony/videos-book15/page-098.mp4 https://www.youtube.com/embed/WeGMOYkT6_0 110 2026-10-04T02:50:01+00:00 yes https://xdme.com/watch-book15-q099.html https://xdme.com/book15-thumbs/page-099.jpg How Do Robots Sort Parcels So Fast? Robots sort parcels fast by reading a label on each one as it rides a belt! A computer decides which bin each parcel belongs in. Then a small arm, pusher, or tilting tray sends it https://socialmedia.xdme.com/tony/videos-book15/page-099.mp4 https://www.youtube.com/embed/VBZB8DSmBdI 112 2026-10-04T02:53:32+00:00 yes https://xdme.com/watch-book15-q100.html https://xdme.com/book15-thumbs/page-100.jpg Why Can't One Robot Cook, Clean, and Fold Laundry Yet? One robot can't cook, clean, and fold laundry yet because each job is very different! Each needs different tools, senses, and skills. Specialist robots are easier to make than all- https://socialmedia.xdme.com/tony/videos-book15/page-100.mp4 https://www.youtube.com/embed/S68NSLh1hvU 115 2026-10-04T02:56:34+00:00 yes https://xdme.com/watch-book15-q101.html https://xdme.com/book15-thumbs/page-101.jpg Why Do Most Small Drones Have Four Rotors? Most small drones have four rotors because four gives a great mix of balance and control! Each rotor pushes air downward to hold the drone up. Speeding up some rotors and slowing o https://socialmedia.xdme.com/tony/videos-book15/page-101.mp4 https://www.youtube.com/embed/0DBwgPf7LWs 113 2026-10-04T03:00:06+00:00 yes https://xdme.com/watch-book15-q102.html https://xdme.com/book15-thumbs/page-102.jpg How Does a Drone Stay Level in the Air? A drone stays level because it feels every tiny tilt and fixes it, hundreds of times each second! A small sensor notices if one side dips. A tiny computer then adjusts the motors t https://socialmedia.xdme.com/tony/videos-book15/page-102.mp4 https://www.youtube.com/embed/GHUThk_Nq4A 111 2026-10-04T03:03:08+00:00 yes https://xdme.com/watch-book15-q103.html https://xdme.com/book15-thumbs/page-103.jpg Why Do Two of a Drone's Propellers Spin One Way and Two the Other? Two propellers spin one way and two spin the other so the drone stays pointing straight! Every spinning propeller gives the drone body a small twist in the opposite direction. Spin https://socialmedia.xdme.com/tony/videos-book15/page-103.mp4 https://www.youtube.com/embed/GZrErAhngK8 115 2026-10-04T03:06:10+00:00 yes https://xdme.com/watch-book15-q104.html https://xdme.com/book15-thumbs/page-104.jpg Why Does a Drone Tilt to Fly Forward? A drone tilts to fly forward because a tilt turns its up-and-down push into a forward push! The rotors push air backward as well as down. Pushing air back moves the drone forward. https://socialmedia.xdme.com/tony/videos-book15/page-104.mp4 https://www.youtube.com/embed/5ehoHNZxYDo 104 2026-10-04T03:13:42+00:00 yes https://xdme.com/watch-book15-q105.html https://xdme.com/book15-thumbs/page-105.jpg Why Can't Most Drones Fly for Very Long? Most drones can't fly for very long because holding themselves up takes a lot of power! A drone must push air downward all the time, or it falls. Most small drones fly for about 20 https://socialmedia.xdme.com/tony/videos-book15/page-105.mp4 https://www.youtube.com/embed/5c0cPb_ArqA 109 2026-10-04T03:16:44+00:00 yes https://xdme.com/watch-book15-q106.html https://xdme.com/book15-thumbs/page-106.jpg Why Do Some Drones Have Little Cages Around the Propellers? Some drones have little cages around their propellers to keep the spinning blades and everything nearby safe! If the drone bumps into something, the cage takes the hit. That protec https://socialmedia.xdme.com/tony/videos-book15/page-106.mp4 https://www.youtube.com/embed/GBweI7rnnKw 112 2026-10-04T03:20:15+00:00 yes https://xdme.com/watch-book15-q107.html https://xdme.com/book15-thumbs/page-107.jpg Why Must Drones Stay Away From Airports and Crowds? Drones must stay away from airports and crowds because flying safely means keeping everyone safe! A drone that falls or crashes could hurt someone or damage things. Rules tell pilo https://socialmedia.xdme.com/tony/videos-book15/page-107.mp4 https://www.youtube.com/embed/Na5Ra2fayj4 113 2026-10-04T03:32:55+00:00 yes https://xdme.com/watch-book15-q108.html https://xdme.com/book15-thumbs/page-108.jpg How Can a Drone Help a Farmer Check a Big Field? A drone can help a farmer check a big field by flying over it and taking photos from above! Special cameras can tell healthy plants from stressed ones. Then the farmer knows where https://socialmedia.xdme.com/tony/videos-book15/page-108.mp4 https://www.youtube.com/embed/3tWNybEjTBk 112 2026-10-04T03:47:24+00:00 yes https://xdme.com/watch-book15-q109.html https://xdme.com/book15-thumbs/page-109.jpg How Do Drones Make Maps and 3D Models? Drones make maps and 3D models by taking hundreds of photos and letting a computer do the math! Each photo is taken from a slightly different place. The differences tell the comput https://socialmedia.xdme.com/tony/videos-book15/page-109.mp4 https://www.youtube.com/embed/S06D13g6jcU 116 2026-10-04T04:01:33+00:00 yes https://xdme.com/watch-book15-q110.html https://xdme.com/book15-thumbs/page-110.jpg Why Can Drone Light Shows Paint Pictures in the Night Sky? Drone light shows paint pictures in the night sky because each drone is a flying dot of light! A computer plans where every drone should be at every moment. Together, hundreds of l https://socialmedia.xdme.com/tony/videos-book15/page-110.mp4 https://www.youtube.com/embed/xi3EOEt4n7I 111 2026-10-04T04:14:37+00:00 yes https://xdme.com/watch-book15-q111.html https://xdme.com/book15-thumbs/page-111.jpg How Do Delivery Drones Carry Packages? Delivery drones carry packages on a hook or in a small box and set them down gently at the spot! They fly high to stay clear of trees and buildings. Because of the battery, they ca https://socialmedia.xdme.com/tony/videos-book15/page-111.mp4 https://www.youtube.com/embed/ArEh3xZQADs 114 2026-10-04T04:22:08+00:00 yes https://xdme.com/watch-book15-q112.html https://xdme.com/book15-thumbs/page-112.jpg How Do Scientists Use Drones to Study Tall Trees and Forest Canopies? Scientists use small drones to study tall trees because drones can fly right up to the treetops! Tree canopies are full of leaves, branches, and animals, high above the ground. The https://socialmedia.xdme.com/tony/videos-book15/page-112.mp4 https://www.youtube.com/embed/gQLniUacFyY 113 2026-10-04T04:29:40+00:00 yes https://xdme.com/watch-book15-q113.html https://xdme.com/book15-thumbs/page-113.jpg Why Can a Drone Hover but an Airplane Can't? A drone can hover because its propellers are tiny spinning wings, but an airplane's wings must keep moving forward! Wings make lift only when air flows past them. A drone's spinnin https://socialmedia.xdme.com/tony/videos-book15/page-113.mp4 https://www.youtube.com/embed/MhjfuDd0df0 109 2026-10-04T04:37:12+00:00 yes https://xdme.com/watch-book15-q114.html https://xdme.com/book15-thumbs/page-114.jpg Why Is a Rover Not Just a Small Car? A rover is not just a small car because it must drive itself in places where nobody can fix it! It has strong wheels, cameras, tools, and its own power. It is more like a robot sci https://socialmedia.xdme.com/tony/videos-book15/page-114.mp4 https://www.youtube.com/embed/J6rUXEM9tYI 110 2026-10-04T04:44:45+00:00 yes https://xdme.com/watch-book15-q115.html https://xdme.com/book15-thumbs/page-115.jpg How Does a Rover Keep Its Wheels on the Ground Over Bumpy Rocks? Many rovers keep their wheels on bumpy rocks with a clever suspension called a rocker-bogie! Each side has wheels joined by pivoting arms. When one wheel goes up, the arms tilt so https://socialmedia.xdme.com/tony/videos-book15/page-115.mp4 https://www.youtube.com/embed/Aufu3dEehaQ 106 2026-10-04T04:52:47+00:00 yes https://xdme.com/watch-book15-q116.html https://xdme.com/book15-thumbs/page-116.jpg Why Does a Rover Only Drive a Little Bit at a Time? A rover drives only a little bit at a time because messages from Earth take minutes to arrive! So engineers can't steer it live, like a toy car. Instead, they send a plan and the r https://socialmedia.xdme.com/tony/videos-book15/page-116.mp4 https://www.youtube.com/embed/z4IeI2GsOCE 113 2026-10-04T05:00:19+00:00 yes https://xdme.com/watch-book15-q117.html https://xdme.com/book15-thumbs/page-117.jpg Why Do Rovers Carry Rock-Zapping Lasers and Drills? Rovers carry rock-zapping lasers and drills to find out what rocks are made of! A laser zaps a rock and makes a tiny puff of glowing gas. Drills collect samples from inside the roc https://socialmedia.xdme.com/tony/videos-book15/page-117.mp4 https://www.youtube.com/embed/89E6JAj9RTg 111 2026-10-04T05:07:51+00:00 yes https://xdme.com/watch-book15-q118.html https://xdme.com/book15-thumbs/page-118.jpg How Do Rovers Get Power on Other Worlds? Rovers get power on other worlds from solar panels or from a special long-lasting battery! The choice depends on where the rover is going. Sunlight can be weak, dusty, or missing f https://socialmedia.xdme.com/tony/videos-book15/page-118.mp4 https://www.youtube.com/embed/TRzQ5OWRu5w 113 2026-10-04T05:15:53+00:00 yes https://xdme.com/watch-book15-q119.html https://xdme.com/book15-thumbs/page-119.jpg Why Do Rovers Have Cameras on Tall Masts? Rovers have cameras on tall masts so they can see farther, like standing on tiptoe! Height lets a camera look over rocks and bumps, so it can see what lies ahead. That helps the te https://socialmedia.xdme.com/tony/videos-book15/page-119.mp4 https://www.youtube.com/embed/vqgkkCxb3J4 106 2026-10-04T05:23:25+00:00 yes https://xdme.com/watch-book15-q120.html https://xdme.com/book15-thumbs/page-120.jpg Why Do We Send Rovers to the Moon? We send rovers to the Moon because it is close, so it is a great place to test machines! Rovers can study rocks, dust, and even search for ice. What we learn helps us prepare for f https://socialmedia.xdme.com/tony/videos-book15/page-120.mp4 https://www.youtube.com/embed/gENOmvOeLuE 109 2026-10-04T05:30:57+00:00 yes https://xdme.com/watch-book15-q121.html https://xdme.com/book15-thumbs/page-121.jpg How Do Underwater Robots Take Pictures in the Dark Deep? Underwater robots take pictures in the dark deep by bringing their own bright lights! Sunlight does not reach the deep ocean. Robots also use sound to sense the seafloor. https://socialmedia.xdme.com/tony/videos-book15/page-121.mp4 https://www.youtube.com/embed/y2JLm__9_MM 114 2026-10-04T05:38:28+00:00 yes https://xdme.com/watch-book15-q122.html https://xdme.com/book15-thumbs/page-122.jpg Why Do Some Underwater Robots Glide by Changing Their Weight? Some underwater robots glide by changing their weight, pumping oil in and out of a bladder! Making itself lighter or heavier is the whole trick. Wings then turn up-and-down motion https://socialmedia.xdme.com/tony/videos-book15/page-122.mp4 https://www.youtube.com/embed/cmgQIqZLRUY 109 2026-10-04T05:46:32+00:00 yes https://xdme.com/watch-book15-q123.html https://xdme.com/book15-thumbs/page-123.jpg How Do Robots Explore Caves That Are Too Narrow for People? Robots explore caves that are too narrow for people because they can be small, bendy, and brave! Caves are narrow, twisty, and have no GPS. Robots go in with cameras and send maps https://socialmedia.xdme.com/tony/videos-book15/page-123.mp4 https://www.youtube.com/embed/aOcKBUXrovA 113 2026-10-04T05:54:05+00:00 yes https://xdme.com/watch-book15-q124.html https://xdme.com/book15-thumbs/page-124.jpg Why Do Engineers Copy Animals When They Build Robots? Engineers copy animals when they build robots because animals have been solving problems for millions of years! Nature has already tested many good designs. This clever idea is cal https://socialmedia.xdme.com/tony/videos-book15/page-124.mp4 https://www.youtube.com/embed/8FOYomdKqnc 120 2026-10-04T06:02:07+00:00 yes https://xdme.com/watch-book15-q125.html https://xdme.com/book15-thumbs/page-125.jpg Why Do Swarms of Tiny Robots Work Together Like Ants? Swarms of tiny robots work together like ants because each one follows a few simple rules! Each robot senses only its neighbors. Together, they can do big jobs, like searching a la https://socialmedia.xdme.com/tony/videos-book15/page-125.mp4 https://www.youtube.com/embed/LfeIyPdNxbE 114 2026-10-04T06:09:39+00:00 yes https://xdme.com/watch-book15-q126.html https://xdme.com/book15-thumbs/page-126.jpg How Does a Robot Decide What to Do Next? A robot decides what to do next by following rules that connect what its sensors say to what it should do! The computer checks the rules one at a time. Then it picks an action, and https://socialmedia.xdme.com/tony/videos-book15/page-126.mp4 https://www.youtube.com/embed/ySZcVlhX6Bc 110 2026-10-04T06:17:12+00:00 yes https://xdme.com/watch-book15-q127.html https://xdme.com/book15-thumbs/page-127.jpg Why Must Instructions for a Robot Be So Exact? Instructions for a robot must be exact because a computer can't guess what you mean! People fill in missing details without noticing. A robot only does exactly what the instruction https://socialmedia.xdme.com/tony/videos-book15/page-127.mp4 https://www.youtube.com/embed/Ve3dSS55Keo 111 2026-10-04T06:24:44+00:00 yes https://xdme.com/watch-book15-q128.html https://xdme.com/book15-thumbs/page-128.jpg Why Do Robot Instructions Use If-Then Rules? Robot instructions use if-then rules so a robot can make choices when things change! An if-then rule says: if something is true, then do an action. For example, if the light is red https://socialmedia.xdme.com/tony/videos-book15/page-128.mp4 https://www.youtube.com/embed/ww0dbzDT7qY 110 2026-10-04T06:32:17+00:00 yes https://xdme.com/watch-book15-q129.html https://xdme.com/book15-thumbs/page-129.jpg Why Does a Robot Check, Act, and Check Again? A robot checks, acts, and checks again because the world changes while it works! A wheel might slip, or someone might step in front. Checking after each move lets the robot correct https://socialmedia.xdme.com/tony/videos-book15/page-129.mp4 https://www.youtube.com/embed/JoE4H3ONdPo 108 2026-10-04T06:39:49+00:00 yes https://xdme.com/watch-book15-q130.html https://xdme.com/book15-thumbs/page-130.jpg Why Can a Robot Get Out of a Maze by Always Turning Left? A robot can get out of a maze by always turning left because it follows one simple wall rule! It keeps one side touching the wall as it moves. That path leads along the walls, all https://socialmedia.xdme.com/tony/videos-book15/page-130.mp4 https://www.youtube.com/embed/RGoQlffLtsI 107 2026-10-04T06:47:20+00:00 yes https://xdme.com/watch-book15-q131.html https://xdme.com/book15-thumbs/page-131.jpg Why Do Robots Need Maps or Landmarks? Robots need maps or landmarks because a robot has to know where it is before it can decide where to go! A map shows the places, and landmarks help the robot find its spot on the ma https://socialmedia.xdme.com/tony/videos-book15/page-131.mp4 https://www.youtube.com/embed/uj1UsXWNAeM 112 2026-10-04T06:54:53+00:00 yes https://xdme.com/watch-book15-q132.html https://xdme.com/book15-thumbs/page-132.jpg Why Do Robots Take Tiny Measurements Many Times a Second? Robots take tiny measurements many times a second so they can notice and fix small problems right away! If a robot checks only once a second, it could drift far off course. Checkin https://socialmedia.xdme.com/tony/videos-book15/page-132.mp4 https://www.youtube.com/embed/WcGDLGVuFzM 113 2026-10-04T07:02:26+00:00 yes https://xdme.com/watch-book15-q133.html https://xdme.com/book15-thumbs/page-133.jpg Why Can a Robot Fail Even When It Follows Every Step Perfectly? A robot can fail even when it follows every step perfectly if the world is different from what the steps expected! The instructions were fine, but they did not cover that surprise. https://socialmedia.xdme.com/tony/videos-book15/page-133.mp4 https://www.youtube.com/embed/Z0oYZkJNVZE 112 2026-10-04T07:09:59+00:00 yes https://xdme.com/watch-book15-q134.html https://xdme.com/book15-thumbs/page-134.jpg How Does a Robot Know When Its Job Is Finished? A robot knows its job is finished when a test in its program becomes true! Sensors check the test again and again. When the answer is yes, the robot stops. https://socialmedia.xdme.com/tony/videos-book15/page-134.mp4 https://www.youtube.com/embed/rU8W2hX_46w 106 2026-10-04T07:17:31+00:00 yes https://xdme.com/watch-book15-q135.html https://xdme.com/book15-thumbs/page-135.jpg What Does a Robot Do When Something Blocks Its Path? When something blocks its path, a robot stops, thinks, and tries a plan B! First, a sensor notices the blockage. Then the robot picks a new route, waits, or asks for help. https://socialmedia.xdme.com/tony/videos-book15/page-135.mp4 https://www.youtube.com/embed/4dDJ6YQdI4Q 107 2026-10-04T07:24:33+00:00 yes https://xdme.com/watch-book15-q136.html https://xdme.com/book15-thumbs/page-136.jpg Why Do Some Robots Remember Where They Have Been? Some robots remember where they have been by keeping a record of their path or a map of what they have seen! That helps them avoid going over the same ground again. It also helps t https://socialmedia.xdme.com/tony/videos-book15/page-136.mp4 https://www.youtube.com/embed/QEr4nkOEQJ0 111 2026-10-04T07:32:14+00:00 yes https://xdme.com/watch-book15-q137.html https://xdme.com/book15-thumbs/page-137.jpg How Can a Robot Arm Learn by Trying Again and Again? A robot arm can learn by trying again and again, keeping the changes that help! This is called trial and error. After many tries, the arm gets better. https://socialmedia.xdme.com/tony/videos-book15/page-137.mp4 https://www.youtube.com/embed/_66SeGYeJ2k 104 2026-10-04T07:39:46+00:00 yes https://xdme.com/watch-book15-q138.html https://xdme.com/book15-thumbs/page-138.jpg Why Do Builders Test Robot Ideas with Cardboard First? Builders test robot ideas with cardboard first because cardboard is cheap and easy to change! A model can be changed in minutes. Mistakes found early are cheap and quick to fix. https://socialmedia.xdme.com/tony/videos-book15/page-138.mp4 https://www.youtube.com/embed/LaXSIqFb_bw 112 2026-10-04T07:47:18+00:00 yes https://xdme.com/watch-book15-q139.html https://xdme.com/book15-thumbs/page-139.jpg What Happens at a Kids' Robot-Building Contest? At a kids' robot-building contest, teams build robots to meet a challenge and cheer each other on! They test, fix problems, and try again as time runs out. Everyone shares ideas an https://socialmedia.xdme.com/tony/videos-book15/page-139.mp4 https://www.youtube.com/embed/xjOjMgIyxU8 114 2026-10-04T07:54:51+00:00 yes https://xdme.com/watch-book15-q140.html https://xdme.com/book15-thumbs/page-140.jpg How Can a Game of Robot Says with a Friend Show How a Robot Reads Steps? A game of Robot Says shows how a robot reads steps, because the robot player does exactly what is said! No more and no less. If the steps are clear and in the right order, the robo https://socialmedia.xdme.com/tony/videos-book15/page-140.mp4 https://www.youtube.com/embed/oP4jxYNOv1M 108 2026-10-04T08:02:24+00:00 yes https://xdme.com/watch-book15-q141.html https://xdme.com/book15-thumbs/page-141.jpg How Can You Build a Cardboard Robot Arm That Really Grips? You can build a cardboard robot arm that really grips with cardboard strips, paper fasteners, string, and a rubber band! The strips are the arm parts, and the fasteners are the joi https://socialmedia.xdme.com/tony/videos-book15/page-141.mp4 https://www.youtube.com/embed/lu4fyqn36lI 110 2026-10-04T08:09:56+00:00 yes https://xdme.com/watch-book15-q142.html https://xdme.com/book15-thumbs/page-142.jpg Why Do Robot Builders Wear Safety Glasses? Robot builders wear safety glasses to protect their eyes while they work! Building uses tools, springs, rubber bands, and small parts. Safety glasses are a quick habit that keeps m https://socialmedia.xdme.com/tony/videos-book15/page-142.mp4 https://www.youtube.com/embed/5KOtkV9n4UA 117 2026-10-04T08:17:59+00:00 yes https://xdme.com/watch-book15-q143.html https://xdme.com/book15-thumbs/page-143.jpg Why Do Robot Batteries Need Extra Care? Robot batteries need extra care because they store a lot of energy in a small package! Handled properly, they are safe and useful. A grown-up should always be in charge of them. https://socialmedia.xdme.com/tony/videos-book15/page-143.mp4 https://www.youtube.com/embed/FcJ-ooohbW0 115 2026-10-04T08:25:32+00:00 yes https://xdme.com/watch-book15-q144.html https://xdme.com/book15-thumbs/page-144.jpg How Do the Parts of a Robot Send Messages to Each Other? The parts of a robot send messages to each other as tiny electrical signals along wires! Sensors send information to the brain. The brain sends commands to the motors. https://socialmedia.xdme.com/tony/videos-book15/page-144.mp4 https://www.youtube.com/embed/4JfQaEXHv0s 115 2026-10-04T08:33:05+00:00 yes https://xdme.com/watch-book15-q145.html https://xdme.com/book15-thumbs/page-145.jpg Why Are the Best Robots Often the Simplest? The best robots are often the simplest because every extra part is something that could break! A simple robot is cheaper and easier to build. It is also easier to repair. https://socialmedia.xdme.com/tony/videos-book15/page-145.mp4 https://www.youtube.com/embed/zBPNNeO2My4 110 2026-10-04T08:40:37+00:00 yes https://xdme.com/watch-book15-q146.html https://xdme.com/book15-thumbs/page-146.jpg Why Do Some Robots Wait for a Signal Before They Start? Many robots wait for a signal before they start so they begin only when everything is ready and safe! The signal can be a button press, a sensor trigger, or a timer. Starting too s https://socialmedia.xdme.com/tony/videos-book15/page-146.mp4 https://www.youtube.com/embed/1wpMQuNGwPg 111 2026-10-04T08:48:09+00:00 yes https://xdme.com/watch-book15-q147.html https://xdme.com/book15-thumbs/page-147.jpg Why Do Engineers Try to Build Robots From Parts That Can Be Reused or Recycled? Engineers try to build robots from parts that can be reused or recycled because making robots uses energy and materials! Robots are made of metals, plastics, and electronics. Reusi https://socialmedia.xdme.com/tony/videos-book15/page-147.mp4 https://www.youtube.com/embed/zZTh2DT7MVc 123 2026-10-04T08:56:13+00:00 yes https://xdme.com/watch-book15-q148.html https://xdme.com/book15-thumbs/page-148.jpg How Do You Keep a Robot Working for Years? You keep a robot working for years the same way you care for a bike, with regular cleaning, checking, and charging! Dirt blocks sensors, wheels wear out, and batteries lose power o https://socialmedia.xdme.com/tony/videos-book15/page-148.mp4 https://www.youtube.com/embed/pV92kCItXVo 112 2026-10-04T09:03:46+00:00 yes https://xdme.com/watch-book15-q149.html https://xdme.com/book15-thumbs/page-149.jpg Why Do Inventors Start with a Problem Before They Design a Robot? Inventors start with a problem before they design a robot so the invention is truly useful! First they learn who needs help and what is hard. Then they design a solution. https://socialmedia.xdme.com/tony/videos-book15/page-149.mp4 https://www.youtube.com/embed/ToX-qLP5oSU 111 2026-10-04T09:10:50+00:00 yes https://xdme.com/watch-book15-q150.html https://xdme.com/book15-thumbs/page-150.jpg What Could Robots Help Scientists Explore Next? Robots could help scientists explore places that are too dangerous or too far for people! Think of caves on Mars, the deep ocean, or icy moons with hidden oceans. Each trip teaches https://socialmedia.xdme.com/tony/videos-book15/page-150.mp4 https://www.youtube.com/embed/1N-iTDR8A1c 113 2026-10-04T09:18:55+00:00 yes https://xdme.com/watch-book16-q001.html https://xdme.com/book16-thumbs/page-001.jpg What Counts as a Desert? A desert is a place that gets very little rain or snow, usually less than 10 inches in a whole year! It is the dryness that makes a desert, not the heat or the sand. Deserts cover https://socialmedia.xdme.com/tony/videos-book16/page-001.mp4 https://www.youtube.com/embed/jvAeGFKOcS8 117 2026-10-04T12:16:02+00:00 yes https://xdme.com/watch-book16-q002.html https://xdme.com/book16-thumbs/page-002.jpg Are All Deserts Hot and Sandy? No, not all deserts are hot and sandy! Many deserts are covered with rock, gravel, or hard-packed dirt, and some even get freezing winters and snow. What every desert shares is ver https://socialmedia.xdme.com/tony/videos-book16/page-002.mp4 https://www.youtube.com/embed/BLkQop3KgXk 117 2026-10-04T12:16:04+00:00 yes https://xdme.com/watch-book16-q003.html https://xdme.com/book16-thumbs/page-003.jpg How Big Is the Sahara? The Sahara in North Africa is the largest hot desert on Earth! It stretches about 3,000 miles, or almost 5,000 kilometers, from the Atlantic Ocean to the Red Sea. It covers an area https://socialmedia.xdme.com/tony/videos-book16/page-003.mp4 https://www.youtube.com/embed/bIa1Rw2YI3E 120 2026-10-04T12:16:05+00:00 yes https://xdme.com/watch-book16-q004.html https://xdme.com/book16-thumbs/page-004.jpg Why Was the Sahara Green Thousands of Years Ago? About 10,000 to 6,000 years ago, the Sahara had lakes, grassy plains, and animals like hippos! Earth wobbles very slowly as it spins around the Sun, and that wobble moved the rainy https://socialmedia.xdme.com/tony/videos-book16/page-004.mp4 https://www.youtube.com/embed/yZam82wDI0g 125 2026-10-04T12:16:06+00:00 yes https://xdme.com/watch-book16-q005.html https://xdme.com/book16-thumbs/page-005.jpg Why Is the Atacama One of the Driest Places on Earth? The Atacama Desert in Chile sits between two huge barriers, and that makes it one of the driest places on Earth! Some weather stations there have gone years with no measurable rain https://socialmedia.xdme.com/tony/videos-book16/page-005.mp4 https://www.youtube.com/embed/GZOpRcVUgMQ 119 2026-10-04T12:16:08+00:00 yes https://xdme.com/watch-book16-q006.html https://xdme.com/book16-thumbs/page-006.jpg Why Is Antarctica Called a Desert Even Though It Is Covered in Ice? A desert is a place that gets very little rain or snow, and the heat does not matter! The inside of Antarctica is so cold and dry that it gets only a couple of inches of snowfall a https://socialmedia.xdme.com/tony/videos-book16/page-006.mp4 https://www.youtube.com/embed/3vy1P4tHZTk 116 2026-10-04T12:17:20+00:00 yes https://xdme.com/watch-book16-q007.html https://xdme.com/book16-thumbs/page-007.jpg Why Are Desert Sand Grains So Round and Frosted? Wind bounces sand grains along the ground, and every bump rubs off their sharp corners! After thousands of years of tumbling, the grains become round with a dull, frosted surface. https://socialmedia.xdme.com/tony/videos-book16/page-007.mp4 https://www.youtube.com/embed/lfHJkk9A8Lo 116 2026-10-04T12:23:03+00:00 yes https://xdme.com/watch-book16-q008.html https://xdme.com/book16-thumbs/page-008.jpg How Do Sand Dunes Form? Sand dunes form when wind blows sand along the ground and a bump or plant slows it down! A small pile forms, and the pile grows because it blocks more wind. Over many years, it gro https://socialmedia.xdme.com/tony/videos-book16/page-008.mp4 https://www.youtube.com/embed/N6-zczZLDT0 109 2026-10-04T12:26:06+00:00 yes https://xdme.com/watch-book16-q009.html https://xdme.com/book16-thumbs/page-009.jpg Why Do Dunes Have a Gentle Slope on One Side and a Steep Slope on the Other? A dune has a gentle slope on the side facing the wind, and a steep slope on the other side! Wind pushes sand up the gentle side, and at the top the sand spills over the crest. The https://socialmedia.xdme.com/tony/videos-book16/page-009.mp4 https://www.youtube.com/embed/fTf5Ar5oZJg 114 2026-10-04T12:29:17+00:00 yes https://xdme.com/watch-book16-q010.html https://xdme.com/book16-thumbs/page-010.jpg Why Do Dunes Slowly Move Across the Land? Dunes move because the wind blows grains up the gentle side, over the top, and down the steep slip face! Grain by grain, the back edge is eaten away and the front edge builds up. S https://socialmedia.xdme.com/tony/videos-book16/page-010.mp4 https://www.youtube.com/embed/rKPv1kdBgNQ 111 2026-10-04T12:31:50+00:00 yes https://xdme.com/watch-book16-q011.html https://xdme.com/book16-thumbs/page-011.jpg Why Do Desert Rocks End Up in Strange Wind-Carved Shapes? Wind carries sand that acts like natural sandpaper, and it slowly carves rocks into strange shapes! Softer layers wear away faster than harder ones. Over thousands of years, that l https://socialmedia.xdme.com/tony/videos-book16/page-011.mp4 https://www.youtube.com/embed/XEYuZSzKOug 116 2026-10-04T12:34:53+00:00 yes https://xdme.com/watch-book16-q012.html https://xdme.com/book16-thumbs/page-012.jpg How Do Stone Arches Form in the Desert? Stone arches start as cracks in thick walls of rock! Rain seeps in, freezes on cold nights, and widens the cracks. Slowly a hole appears, and if the rock above is strong enough, it https://socialmedia.xdme.com/tony/videos-book16/page-012.mp4 https://www.youtube.com/embed/Mk_jmRbzY-A 109 2026-10-04T12:37:56+00:00 yes https://xdme.com/watch-book16-q013.html https://xdme.com/book16-thumbs/page-013.jpg What Is Desert Pavement? Desert pavement is a flat patch of desert covered with tightly packed stones that look like a tile floor! Wind and rain blow and wash away the fine dust and sand, leaving the pebbl https://socialmedia.xdme.com/tony/videos-book16/page-013.mp4 https://www.youtube.com/embed/JiJ8Zcr2DrQ 110 2026-10-04T12:40:58+00:00 yes https://xdme.com/watch-book16-q014.html https://xdme.com/book16-thumbs/page-014.jpg Why Are Some Desert Rocks Coated in a Dark, Shiny Skin? That dark coating is called desert varnish! It forms very slowly when dust with iron and manganese settles on rock. Tiny microbes and weather help cement it in place. https://socialmedia.xdme.com/tony/videos-book16/page-014.mp4 https://www.youtube.com/embed/uJkAV9YrQ0o 112 2026-10-04T12:51:01+00:00 yes https://xdme.com/watch-book16-q015.html https://xdme.com/book16-thumbs/page-015.jpg How Can Salt Break a Rock? Salt can break a rock by growing crystals inside its tiny cracks! Rainwater or groundwater that seeps into rocks carries dissolved salt. When the water dries up, the salt crystals https://socialmedia.xdme.com/tony/videos-book16/page-015.mp4 https://www.youtube.com/embed/aKWumd2E6NM 115 2026-10-04T12:53:34+00:00 yes https://xdme.com/watch-book16-q016.html https://xdme.com/book16-thumbs/page-016.jpg Why Do Some Deserts Have Flat White Salt Plains? Flat white salt plains form when water evaporates and leaves its salt behind! Rivers carry dissolved salt into low basins that have no outlet to the sea. After thousands of years, https://socialmedia.xdme.com/tony/videos-book16/page-016.mp4 https://www.youtube.com/embed/FrGCX0YoC78 119 2026-10-04T12:56:39+00:00 yes https://xdme.com/watch-book16-q017.html https://xdme.com/book16-thumbs/page-017.jpg Why Does Dry Mud Crack Into Puzzle Pieces? When wet mud dries, it shrinks because the water leaves! The mud cannot shrink evenly, so tension builds up until it splits. The cracks make a pattern like puzzle pieces. https://socialmedia.xdme.com/tony/videos-book16/page-017.mp4 https://www.youtube.com/embed/OyaIpnN5Xu0 110 2026-10-04T12:59:42+00:00 yes https://xdme.com/watch-book16-q018.html https://xdme.com/book16-thumbs/page-018.jpg Why Are Desert Rocks So Often Red, Orange, or Pink? Many desert rocks contain iron! When iron meets air and a little moisture, it rusts, forming red and orange minerals. That rust coats the sand grains and paints the rocks. https://socialmedia.xdme.com/tony/videos-book16/page-018.mp4 https://www.youtube.com/embed/7dyGVABi5q8 108 2026-10-04T13:02:16+00:00 yes https://xdme.com/watch-book16-q019.html https://xdme.com/book16-thumbs/page-019.jpg Why Do Fossils of Sea Creatures Turn Up in Some Deserts? Parts of some deserts used to lie under warm, shallow seas millions of years ago! Shells and sea animals sank into the mud, and the mud hardened into rock. Later the sea went away https://socialmedia.xdme.com/tony/videos-book16/page-019.mp4 https://www.youtube.com/embed/fjzsUAk4wH4 113 2026-10-04T13:05:19+00:00 yes https://xdme.com/watch-book16-q020.html https://xdme.com/book16-thumbs/page-020.jpg How Does Wood Turn Into Stone? A fallen tree can turn into stone over millions of years! If it is buried quickly by mud or ash, little air reaches it, so it does not rot. Minerals then slowly replace the wood an https://socialmedia.xdme.com/tony/videos-book16/page-020.mp4 https://www.youtube.com/embed/y6yQJAj955A 110 2026-10-04T13:07:53+00:00 yes https://xdme.com/watch-book16-q021.html https://xdme.com/book16-thumbs/page-021.jpg Why Do Giant Sandstorms Roll Across Deserts? Giant sandstorms happen when strong winds blow across loose, dry ground! The wind lifts sand and dust high into the air. Sometimes the dust forms a huge rolling wall that looks lik https://socialmedia.xdme.com/tony/videos-book16/page-021.mp4 https://www.youtube.com/embed/Y0wnx0J5PDI 109 2026-10-04T13:10:55+00:00 yes https://xdme.com/watch-book16-q022.html https://xdme.com/book16-thumbs/page-022.jpg How Can Desert Dust Blow Across a Whole Ocean? Winds can carry fine desert dust high into the air, where it rides along for thousands of miles! Dust from the Sahara blows across the Atlantic Ocean in about a week. It reaches th https://socialmedia.xdme.com/tony/videos-book16/page-022.mp4 https://www.youtube.com/embed/v-kdr-TbTPg 112 2026-10-04T13:13:30+00:00 yes https://xdme.com/watch-book16-q023.html https://xdme.com/book16-thumbs/page-023.jpg Why Are Deserts Good Places to Find Meteorites? Deserts are great places to find meteorites, which are space rocks that fall to Earth! Meteorites look like dark rocks, and deserts are mostly pale with few plants to hide them. Th https://socialmedia.xdme.com/tony/videos-book16/page-023.mp4 https://www.youtube.com/embed/TTAffbhRzHo 112 2026-10-04T13:16:33+00:00 yes https://xdme.com/watch-book16-q024.html https://xdme.com/book16-thumbs/page-024.jpg Why Does the Desert Sky Seem to Sparkle with Stars at Night? The desert sky sparkles with stars because desert air is dry and often very clear! There are few clouds and little haze to blur the starlight. Many deserts are also far from city l https://socialmedia.xdme.com/tony/videos-book16/page-024.mp4 https://www.youtube.com/embed/mCHmxas0HsY 111 2026-10-04T13:19:06+00:00 yes https://xdme.com/watch-book16-q025.html https://xdme.com/book16-thumbs/page-025.jpg How Do Scientists Use Deserts to Practice for Mars? Some deserts are dry, rocky, and cold at night, a bit like Mars! Scientists test rovers, drills, and spacesuits in places like the Atacama and the Utah desert. It is a safe place t https://socialmedia.xdme.com/tony/videos-book16/page-025.mp4 https://www.youtube.com/embed/kmH4pcQ4Ss8 112 2026-10-04T13:22:09+00:00 yes https://xdme.com/watch-book16-q026.html https://xdme.com/book16-thumbs/page-026.jpg How Do Living Things Stay Cool in a Place with No Air Conditioning? Desert plants and animals use many clever tricks instead of cooling machines! They rest in shade or underground, come out when it is cooler, and wear pale colors that reflect sunli https://socialmedia.xdme.com/tony/videos-book16/page-026.mp4 https://www.youtube.com/embed/7THgEi0QTcs 112 2026-10-04T13:25:12+00:00 yes https://xdme.com/watch-book16-q027.html https://xdme.com/book16-thumbs/page-027.jpg Why Is It So Much Cooler a Few Feet Underground in a Desert? A few feet underground, a desert can be much cooler than the surface! Soil and sand are poor conductors of heat, so the Sun's warmth takes a long time to move downward. That makes https://socialmedia.xdme.com/tony/videos-book16/page-027.mp4 https://www.youtube.com/embed/V7pOcr2-V2s 115 2026-10-04T13:28:15+00:00 yes https://xdme.com/watch-book16-q028.html https://xdme.com/book16-thumbs/page-028.jpg How Do Desert Hunters Find Food on a Dark Night? Many desert night hunters have senses tuned for darkness! They use sound and heat instead of sight, so they can catch food without sunlight. Their senses are amazing tools. https://socialmedia.xdme.com/tony/videos-book16/page-028.mp4 https://www.youtube.com/embed/ash9kCq7otM 112 2026-10-04T13:30:49+00:00 yes https://xdme.com/watch-book16-q029.html https://xdme.com/book16-thumbs/page-029.jpg Why Do Big Ears Help Some Desert Animals Cool Off? Big ears have lots of tiny blood vessels near the surface! When warm blood flows through the thin skin, heat escapes into the air, and the blood returns cooler. Big ears work like https://socialmedia.xdme.com/tony/videos-book16/page-029.mp4 https://www.youtube.com/embed/FPRLkOgLhNc 112 2026-10-04T13:33:52+00:00 yes https://xdme.com/watch-book16-q030.html https://xdme.com/book16-thumbs/page-030.jpg Why Are So Many Desert Animals Pale or Sandy Colored? Light colors reflect more sunlight than dark ones, so a pale coat stays a little cooler! The sandy color also works as camouflage on pale ground. It helps small animals hide from h https://socialmedia.xdme.com/tony/videos-book16/page-030.mp4 https://www.youtube.com/embed/s4yK3_6WD3o 114 2026-10-04T13:36:55+00:00 yes https://xdme.com/watch-book16-q031.html https://xdme.com/book16-thumbs/page-031.jpg Where Do Desert Animals Find Water If There Is No Pond? Many desert animals get most of their water from their food! Seeds, insects, and juicy plants all hold water. Animals also lick morning dew and rain drops, and some travel far to a https://socialmedia.xdme.com/tony/videos-book16/page-031.mp4 https://www.youtube.com/embed/-TZWlslooSs 113 2026-10-04T13:39:28+00:00 yes https://xdme.com/watch-book16-q032.html https://xdme.com/book16-thumbs/page-032.jpg How Can a Kangaroo Rat Live Without Ever Taking a Drink? A kangaroo rat lives its whole life without taking a drink! It eats dry seeds, and its body makes a little water while digesting them. Its kidneys are also extremely good at saving https://socialmedia.xdme.com/tony/videos-book16/page-032.mp4 https://www.youtube.com/embed/VBB_KcT0PFg 109 2026-10-04T13:42:31+00:00 yes https://xdme.com/watch-book16-q033.html https://xdme.com/book16-thumbs/page-033.jpg How Does a Beetle Collect Drinking Water From Fog? In the Namib Desert, fog rolls in from the ocean at dawn, and some beetles use it to drink! Fog droplets gather on the beetle's bumpy back. The tiny drops join together and roll do https://socialmedia.xdme.com/tony/videos-book16/page-033.mp4 https://www.youtube.com/embed/6L5npzZOQUE 118 2026-10-04T13:45:35+00:00 yes https://xdme.com/watch-book16-q034.html https://xdme.com/book16-thumbs/page-034.jpg Why Does Dry Air Make You Feel Thirsty So Fast? In dry air, sweat and moisture from your breath and skin evaporate quickly! So your body loses water faster than you may notice. Then it signals thirst to warn you to drink. https://socialmedia.xdme.com/tony/videos-book16/page-034.mp4 https://www.youtube.com/embed/Aba5R3nigC0 108 2026-10-04T13:48:07+00:00 yes https://xdme.com/watch-book16-q035.html https://xdme.com/book16-thumbs/page-035.jpg Why Should You Sip Water Often on a Hot Day Instead of Waiting Until You Are Very Thirsty? Sip water often on a hot day instead of waiting until you are very thirsty! Your body is mostly water, and it uses water to cool you down when you sweat. If you wait until you feel https://socialmedia.xdme.com/tony/videos-book16/page-035.mp4 https://www.youtube.com/embed/9i01avrjleE 107 2026-10-04T13:50:45+00:00 yes https://xdme.com/watch-book16-q036.html https://xdme.com/book16-thumbs/page-036.jpg Why Is the Afternoon Often the Hottest Part of a Desert Day? You might expect noon to be the hottest time, but the afternoon is usually hotter! The ground keeps soaking up sunshine and passing heat to the air all afternoon. The temperature u https://socialmedia.xdme.com/tony/videos-book16/page-036.mp4 https://www.youtube.com/embed/hxbEsZhO_Nw 114 2026-10-04T13:53:49+00:00 yes https://xdme.com/watch-book16-q037.html https://xdme.com/book16-thumbs/page-037.jpg Why Is Sand Too Hot to Walk on at Midday? Sand gets too hot to walk on because it soaks up the Sun's energy! Dry sand is also not good at carrying heat downward, so the top layer gets very hot. That hot sand can burn bare https://socialmedia.xdme.com/tony/videos-book16/page-037.mp4 https://www.youtube.com/embed/SdHKNSzRlj8 110 2026-10-04T13:56:26+00:00 yes https://xdme.com/watch-book16-q038.html https://xdme.com/book16-thumbs/page-038.jpg How Do Animals Stay Warm on a Cold Desert Night? Desert nights can get chilly, but animals have many ways to stay warm! Burrows, rock crevices, and nests protect them from the cold air above ground. Fur, feathers, and fat trap bo https://socialmedia.xdme.com/tony/videos-book16/page-038.mp4 https://www.youtube.com/embed/35gBCCh_w4E 112 2026-10-04T13:58:59+00:00 yes https://xdme.com/watch-book16-q039.html https://xdme.com/book16-thumbs/page-039.jpg Which Deserts Get Freezing Winters, and Why? Deserts in the middle of big continents, or high up on plateaus, get very cold winters! The Gobi in Asia and the Great Basin in North America are examples. These are called cold de https://socialmedia.xdme.com/tony/videos-book16/page-039.mp4 https://www.youtube.com/embed/IuNnvLEYWJA 110 2026-10-04T14:02:01+00:00 yes https://xdme.com/watch-book16-q040.html https://xdme.com/book16-thumbs/page-040.jpg Why Does Snow Sometimes Fall in Deserts? Snow can fall in deserts because deserts can be high up! The higher you go, the colder the air gets. When a winter storm brings moist air, it may fall as snow instead of rain. https://socialmedia.xdme.com/tony/videos-book16/page-040.mp4 https://www.youtube.com/embed/ww_lQcPjyo8 107 2026-10-04T14:04:42+00:00 yes https://xdme.com/watch-book16-q041.html https://xdme.com/book16-thumbs/page-041.jpg Why Do Lizards Switch Between Sun and Shade All Day? A lizard is cold-blooded, so it uses the outside world to set its body temperature! In the morning it basks on a warm rock to heat up. When it gets too hot, it dashes into shade or https://socialmedia.xdme.com/tony/videos-book16/page-041.mp4 https://www.youtube.com/embed/1g5cn7R3HGI 113 2026-10-04T14:07:14+00:00 yes https://xdme.com/watch-book16-q042.html https://xdme.com/book16-thumbs/page-042.jpg Why Do Some Lizards Lift Their Feet One at a Time on Hot Sand? The shovel-snouted lizard of the Namib Desert does a little dance when the sand is too hot! It raises two feet off the ground while resting on the other two, then switches. Each fo https://socialmedia.xdme.com/tony/videos-book16/page-042.mp4 https://www.youtube.com/embed/OFT-eukkGT0 112 2026-10-04T14:10:18+00:00 yes https://xdme.com/watch-book16-q043.html https://xdme.com/book16-thumbs/page-043.jpg Why Do Saharan Silver Ants Run on Such Long Legs? Saharan silver ants search for food at midday, when it is so hot that other animals hide! Their long legs lift their bodies a little above the burning sand, where the air is cooler https://socialmedia.xdme.com/tony/videos-book16/page-043.mp4 https://www.youtube.com/embed/tkEI5RKeTTc 112 2026-10-04T14:12:50+00:00 yes https://xdme.com/watch-book16-q044.html https://xdme.com/book16-thumbs/page-044.jpg How Do Birds Cool Off Without Sweating? Birds cannot sweat, but they have other ways to cool off! They open their beaks and flutter their throat skin so water evaporates from the mouth and throat. That carries heat away, https://socialmedia.xdme.com/tony/videos-book16/page-044.mp4 https://www.youtube.com/embed/dYLayN6zQIs 113 2026-10-04T14:15:24+00:00 yes https://xdme.com/watch-book16-q045.html https://xdme.com/book16-thumbs/page-045.jpg Why Does a Roadrunner Sunbathe in the Morning? A roadrunner sunbathes in the morning to warm up! A greater roadrunner has dark skin on its back under its feathers. It turns its back to the Sun and lifts its feathers so that ski https://socialmedia.xdme.com/tony/videos-book16/page-045.mp4 https://www.youtube.com/embed/5Zir-Iboyh8 112 2026-10-04T14:18:18+00:00 yes https://xdme.com/watch-book16-q046.html https://xdme.com/book16-thumbs/page-046.jpg What Is Summer Sleep, and Which Animals Do It? Summer sleep is called estivation, and it is a lot like hibernation but in summer! Some animals rest through the hottest, driest months. When rain returns, they wake up and get bus https://socialmedia.xdme.com/tony/videos-book16/page-046.mp4 https://www.youtube.com/embed/EH5AIblRxTQ 113 2026-10-04T14:20:54+00:00 yes https://xdme.com/watch-book16-q047.html https://xdme.com/book16-thumbs/page-047.jpg Why Do Some Desert Insects Have Waxy Skin? Insects lose water through their outer shell, and in a dry place that can be a big problem! Many desert beetles and ants have a waxy layer on the outside. It works like a raincoat https://socialmedia.xdme.com/tony/videos-book16/page-047.mp4 https://www.youtube.com/embed/EZofKnWGOho 114 2026-10-04T14:23:27+00:00 yes https://xdme.com/watch-book16-q048.html https://xdme.com/book16-thumbs/page-048.jpg Why Are There So Few Clouds Over Most Deserts? Many deserts lie where air sinks down from high in the sky! Sinking air warms up and dries out, so clouds rarely form. That is why most deserts have so few clouds. https://socialmedia.xdme.com/tony/videos-book16/page-048.mp4 https://www.youtube.com/embed/0yEacGMEQx8 112 2026-10-04T14:26:30+00:00 yes https://xdme.com/watch-book16-q049.html https://xdme.com/book16-thumbs/page-049.jpg What Happens to a Body That Is Too Hot, and How Can You Help? When you get too hot, your body sweats and your heart works harder! If you cannot cool down, you may feel dizzy, sick, or very tired. Heat can be serious, so always tell a grown-up https://socialmedia.xdme.com/tony/videos-book16/page-049.mp4 https://www.youtube.com/embed/riE_PdLDbTY 106 2026-10-04T14:29:03+00:00 yes https://xdme.com/watch-book16-q050.html https://xdme.com/book16-thumbs/page-050.jpg Where Is the Hottest Place on Earth, and How Hot Does It Get? The hottest air temperature ever officially recorded was 134 degrees Fahrenheit in Death Valley, California, in 1913! That is about 57 degrees Celsius. Death Valley is a very hot, https://socialmedia.xdme.com/tony/videos-book16/page-050.mp4 https://www.youtube.com/embed/xDT78woliQc 120 2026-10-04T14:32:06+00:00 yes https://xdme.com/watch-book16-q051.html https://xdme.com/book16-thumbs/page-051.jpg How Do Plants Survive in Places Where It Almost Never Rains? Desert plants survive with clever tricks for finding, saving, and waiting for water! Some store water in their stems, some grow long roots, and some wait as tiny seeds. Each plan h https://socialmedia.xdme.com/tony/videos-book16/page-051.mp4 https://www.youtube.com/embed/u96r43l2Fg8 118 2026-10-04T14:35:08+00:00 yes https://xdme.com/watch-book16-q052.html https://xdme.com/book16-thumbs/page-052.jpg Why Do Many Desert Plants Have Tiny Leaves or No Leaves at All? Desert plants have tiny leaves or none at all, because leaves lose water! Water escapes through tiny pores in a leaf, especially in hot, dry air. Less leaf means less water lost, a https://socialmedia.xdme.com/tony/videos-book16/page-052.mp4 https://www.youtube.com/embed/XmvYIYA2Gzo 120 2026-10-04T14:37:47+00:00 yes https://xdme.com/watch-book16-q053.html https://xdme.com/book16-thumbs/page-053.jpg Why Do Some Desert Shrubs Send Their Roots Down 50 Feet or More? Some desert shrubs send roots down 50 feet or more to reach water far below! Deep underground, the soil stays damp long after the surface dries out. These long roots work like stra https://socialmedia.xdme.com/tony/videos-book16/page-053.mp4 https://www.youtube.com/embed/b3OT4l9xrxw 117 2026-10-04T14:40:19+00:00 yes https://xdme.com/watch-book16-q054.html https://xdme.com/book16-thumbs/page-054.jpg Why Do Some Desert Plants Spread Their Roots Wide but Shallow? Some desert plants spread their roots wide but shallow to catch rain fast! A desert rain soaks only the top few inches of soil, and it dries quickly. A wide net of roots can drink https://socialmedia.xdme.com/tony/videos-book16/page-054.mp4 https://www.youtube.com/embed/-Br79iH57oI 115 2026-10-04T14:43:22+00:00 yes https://xdme.com/watch-book16-q055.html https://xdme.com/book16-thumbs/page-055.jpg Why Do Desert Wildflowers Bloom All at Once After a Rare Rain? Desert wildflowers bloom all at once because rain wakes up millions of seeds together! The seeds wait in the soil for enough water and mild weather. Then the whole land turns into https://socialmedia.xdme.com/tony/videos-book16/page-055.mp4 https://www.youtube.com/embed/nn-FtzuCIF8 113 2026-10-04T14:45:55+00:00 yes https://xdme.com/watch-book16-q056.html https://xdme.com/book16-thumbs/page-056.jpg How Can a Seed Wait for Years Until It Rains? A desert seed can wait for years, because it has a tough coat and a rain sensor! Chemicals in the coat keep the seed from sprouting too soon. Only a heavy soaking rain washes them https://socialmedia.xdme.com/tony/videos-book16/page-056.mp4 https://www.youtube.com/embed/djnLa2VD_5c 105 2026-10-04T14:48:27+00:00 yes https://xdme.com/watch-book16-q057.html https://xdme.com/book16-thumbs/page-057.jpg Why Does the Creosote Bush Smell Like Rain? The creosote bush smells like rain because its leaves release a fresh scent when they get wet! The smell comes from oils in a waxy coating on the leaves. After a desert storm, the https://socialmedia.xdme.com/tony/videos-book16/page-057.mp4 https://www.youtube.com/embed/Bk70fBjJlYw 114 2026-10-04T14:51:30+00:00 yes https://xdme.com/watch-book16-q058.html https://xdme.com/book16-thumbs/page-058.jpg How Can a Ring of Bushes Be 11,000 Years Old? A ring of creosote bushes can be 11,000 years old, because it is one plant that keeps growing outward! It is called a clone, made of many stems with the same roots and genes. As th https://socialmedia.xdme.com/tony/videos-book16/page-058.mp4 https://www.youtube.com/embed/M8amGZpA7rc 117 2026-10-04T14:54:04+00:00 yes https://xdme.com/watch-book16-q059.html https://xdme.com/book16-thumbs/page-059.jpg How Does a Joshua Tree Depend on One Little Moth? A Joshua tree depends on one little moth, and the moth depends on the tree! It is a partnership where each one helps the other. They have been teammates for a very long time, and n https://socialmedia.xdme.com/tony/videos-book16/page-059.mp4 https://www.youtube.com/embed/GHgLjGvld2k 110 2026-10-04T14:57:07+00:00 yes https://xdme.com/watch-book16-q060.html https://xdme.com/book16-thumbs/page-060.jpg Why Do Some Desert Plants Have Fuzzy or Silvery Leaves? Some desert plants have fuzzy or silvery leaves, because tiny hairs help them stay cool and moist! The hairs slow water loss and bounce sunlight away. Silvery leaves are like a lit https://socialmedia.xdme.com/tony/videos-book16/page-060.mp4 https://www.youtube.com/embed/0OZ7ojO5XGk 114 2026-10-04T14:59:52+00:00 yes https://xdme.com/watch-book16-q061.html https://xdme.com/book16-thumbs/page-061.jpg Why Do Some Desert Plants Open Their Pores Only at Night? Some desert plants open their pores only at night, so they lose less water! Open pores let in air, but they also let water escape. At night, the air is cooler and damper, so it is https://socialmedia.xdme.com/tony/videos-book16/page-061.mp4 https://www.youtube.com/embed/QbxpsEs-b9g 110 2026-10-04T15:02:01+00:00 yes https://xdme.com/watch-book16-q062.html https://xdme.com/book16-thumbs/page-062.jpg Why Are Aloe Leaves So Thick and Gel-Filled? Aloe leaves are thick and gel-filled because they are built to store water! The juicy gel inside holds water for a long time. That helps the plant get through a drought. https://socialmedia.xdme.com/tony/videos-book16/page-062.mp4 https://www.youtube.com/embed/Rr8ojd7nAIw 112 2026-10-04T15:05:04+00:00 yes https://xdme.com/watch-book16-q063.html https://xdme.com/book16-thumbs/page-063.jpg Why Do Some Desert Plants Look Like Pebbles? Some desert plants look like pebbles, so hungry animals walk right past them! They are called living stones, and they grow in southern Africa. Their disguise is a clever way to sta https://socialmedia.xdme.com/tony/videos-book16/page-063.mp4 https://www.youtube.com/embed/8NNGj_5kXBw 111 2026-10-04T15:07:37+00:00 yes https://xdme.com/watch-book16-q064.html https://xdme.com/book16-thumbs/page-064.jpg Why Does the Ocotillo Grow Leaves Only After It Rains? The ocotillo grows leaves only after it rains, so it does not waste water! Most of the year, it looks like a bundle of dead sticks. After rain, it turns green in just a few days. https://socialmedia.xdme.com/tony/videos-book16/page-064.mp4 https://www.youtube.com/embed/QF4f4fzTS28 110 2026-10-04T15:10:20+00:00 yes https://xdme.com/watch-book16-q065.html https://xdme.com/book16-thumbs/page-065.jpg How Can a Resurrection Plant Come Back to Life? A resurrection plant can come back to life, because it only dries out and does not die! It curls into a tight, brown ball and waits. When water arrives, it unfolds and turns green https://socialmedia.xdme.com/tony/videos-book16/page-065.mp4 https://www.youtube.com/embed/7nkiJSUgwq8 112 2026-10-04T15:13:04+00:00 yes https://xdme.com/watch-book16-q066.html https://xdme.com/book16-thumbs/page-066.jpg Why Does a Tumbleweed Roll Across the Land? A tumbleweed rolls across the land to spread its seeds far and wide! When the plant dries, it breaks off and the wind rolls it along. Every bump shakes out more seeds. https://socialmedia.xdme.com/tony/videos-book16/page-066.mp4 https://www.youtube.com/embed/qcoXnFKxExw 109 2026-10-04T15:15:41+00:00 yes https://xdme.com/watch-book16-q067.html https://xdme.com/book16-thumbs/page-067.jpg Why Do So Many Desert Plants Have Thorns or Spines? Desert plants have thorns and spines because they hold precious water, and animals would eat them! Sharp points make a bite painful, so most animals give up. Spines can also do oth https://socialmedia.xdme.com/tony/videos-book16/page-067.mp4 https://www.youtube.com/embed/dZPdhXEZFSw 113 2026-10-04T15:18:15+00:00 yes https://xdme.com/watch-book16-q068.html https://xdme.com/book16-thumbs/page-068.jpg What Is the Welwitschia, the Namib Plant That Lives for Centuries? The welwitschia is a plant from the Namib Desert that can live for centuries! It has just two long, strap-shaped leaves that never stop growing, which is very unusual for a plant. https://socialmedia.xdme.com/tony/videos-book16/page-068.mp4 https://www.youtube.com/embed/VUPi7pAMR1M 113 2026-10-04T15:21:19+00:00 yes https://xdme.com/watch-book16-q069.html https://xdme.com/book16-thumbs/page-069.jpg How Do Desert Plants Avoid Crowding Each Other? Desert plants avoid crowding because there is not enough water for them to be close together! Each plant needs a big patch of ground to collect rain. That is why the gaps are not e https://socialmedia.xdme.com/tony/videos-book16/page-069.mp4 https://www.youtube.com/embed/acHKQKl5xKM 114 2026-10-04T15:23:52+00:00 yes https://xdme.com/watch-book16-q070.html https://xdme.com/book16-thumbs/page-070.jpg Why Do Some Desert Leaves Stand on Edge Instead of Lying Flat? Some desert leaves stand on edge or hang down, so they catch less hot sunlight! It is a clever shade trick that works without any shade at all. Leaves held flat catch the most ligh https://socialmedia.xdme.com/tony/videos-book16/page-070.mp4 https://www.youtube.com/embed/TWZvq4DIsSQ 115 2026-10-04T15:26:26+00:00 yes https://xdme.com/watch-book16-q071.html https://xdme.com/book16-thumbs/page-071.jpg Why Do Big Cacti Have Pleated Sides? Big cacti have pleated sides because the pleats work like an accordion! They let the cactus swell up when it drinks and shrink when the water is used. The pleats are called ribs, a https://socialmedia.xdme.com/tony/videos-book16/page-071.mp4 https://www.youtube.com/embed/rJiIHgZyP14 113 2026-10-04T15:29:28+00:00 yes https://xdme.com/watch-book16-q072.html https://xdme.com/book16-thumbs/page-072.jpg How Do Mesquite Trees Make Poor Desert Soil Richer? Mesquite trees make poor desert soil richer by teaming up with tiny helpers in their roots! Those helpers are bacteria that make plant food from the air. When the leaves fall, the https://socialmedia.xdme.com/tony/videos-book16/page-072.mp4 https://www.youtube.com/embed/ClVW7UyoOOk 114 2026-10-04T15:32:02+00:00 yes https://xdme.com/watch-book16-q073.html https://xdme.com/book16-thumbs/page-073.jpg How Do Animals Help Desert Seeds Spread? Animals help desert seeds spread by carrying, burying, eating, and dropping them! A seed that is moved to a good spot has a much better chance to grow. In a desert, a damp spot is https://socialmedia.xdme.com/tony/videos-book16/page-073.mp4 https://www.youtube.com/embed/tEpihUNwxts 109 2026-10-04T15:34:36+00:00 yes https://xdme.com/watch-book16-q074.html https://xdme.com/book16-thumbs/page-074.jpg Why Do Many Desert Plants Taste Bitter or Smell Strong? Many desert plants taste bitter or smell strong, because those are their way to protect themselves! A plant cannot run away from a hungry animal, and its water and food are preciou https://socialmedia.xdme.com/tony/videos-book16/page-074.mp4 https://www.youtube.com/embed/7l7wN1KobY4 119 2026-10-04T15:37:39+00:00 yes https://xdme.com/watch-book16-q075.html https://xdme.com/book16-thumbs/page-075.jpg What Useful Things Do People Get From Desert Plants? People get many useful things from desert plants, like food, fiber, oil, and shade! People have used desert plants for thousands of years, and they have learned which ones are safe https://socialmedia.xdme.com/tony/videos-book16/page-075.mp4 https://www.youtube.com/embed/yASblnEjNPM 118 2026-10-04T15:40:41+00:00 yes https://xdme.com/watch-book16-q076.html https://xdme.com/book16-thumbs/page-076.jpg How Does a Sidewinder Snake Travel Across Loose Sand? A sidewinder snake travels across loose sand by throwing its body sideways in loops! Only two small spots touch the ground at a time. That gives it grip and keeps most of its body https://socialmedia.xdme.com/tony/videos-book16/page-076.mp4 https://www.youtube.com/embed/Zr9qWRqGnC0 112 2026-10-04T12:17:14+00:00 yes https://xdme.com/watch-book16-q077.html https://xdme.com/book16-thumbs/page-077.jpg Why Does the Thorny Devil Have Spiky Skin and Drink with Its Feet? The thorny devil has spiky skin to stay safe, and it drinks through its skin! Tiny grooves between its scales work like thin straws. They pull water toward its mouth. https://socialmedia.xdme.com/tony/videos-book16/page-077.mp4 https://www.youtube.com/embed/au-Aisg52d4 113 2026-10-04T12:17:15+00:00 yes https://xdme.com/watch-book16-q078.html https://xdme.com/book16-thumbs/page-078.jpg How Do Desert Tortoises Survive Years of Dry Weather? Desert tortoises survive years of dry weather by hiding in burrows and storing water! They drink a lot when they can, then use that water for months. They are real desert survivors https://socialmedia.xdme.com/tony/videos-book16/page-078.mp4 https://www.youtube.com/embed/QVfHPdDXpL4 115 2026-10-04T12:17:18+00:00 yes https://xdme.com/watch-book16-q079.html https://xdme.com/book16-thumbs/page-079.jpg Why Does the Gila Monster Store Fat in Its Tail? The Gila monster stores fat in its tail, like an energy battery for hungry times! It eats only a few big meals a year. The stored fat keeps it going for months. https://socialmedia.xdme.com/tony/videos-book16/page-079.mp4 https://www.youtube.com/embed/1coksEReMp4 110 2026-10-04T12:17:27+00:00 yes https://xdme.com/watch-book16-q080.html https://xdme.com/book16-thumbs/page-080.jpg How Do Spadefoot Toads Live in a Desert? Spadefoot toads live in a desert by burying themselves and waiting for rain! They sleep underground for months, even years, while the desert above them stays dry. When a big rain a https://socialmedia.xdme.com/tony/videos-book16/page-080.mp4 https://www.youtube.com/embed/1ouCjEgiafE 115 2026-10-04T12:17:29+00:00 yes https://xdme.com/watch-book16-q081.html https://xdme.com/book16-thumbs/page-081.jpg Why Do Fairy Shrimp Hatch From Dry Dust After a Rain? Fairy shrimp hatch from dry dust after a rain, because their eggs are made to wait! The eggs have thick shells and can sit dry for many years. Rain fills a puddle, and the eggs wak https://socialmedia.xdme.com/tony/videos-book16/page-081.mp4 https://www.youtube.com/embed/NGJl1nHH_2M 109 2026-10-04T12:17:32+00:00 yes https://xdme.com/watch-book16-q082.html https://xdme.com/book16-thumbs/page-082.jpg How Does a Scorpion Find Its Way and Its Food in the Dark? A scorpion finds its way and its food in the dark by feeling tiny vibrations! Its eyesight is poor, but its legs are super sensitive. It waits for dinner to walk by. https://socialmedia.xdme.com/tony/videos-book16/page-082.mp4 https://www.youtube.com/embed/XYX4EjSRlME 113 2026-10-04T12:23:04+00:00 yes https://xdme.com/watch-book16-q083.html https://xdme.com/book16-thumbs/page-083.jpg How Do Jackrabbits Escape Fast Hunters? Jackrabbits escape fast hunters with speed, zigzags, and super senses! Their strong hind legs launch them forward. Their ears and eyes warn them early, giving them a head start. https://socialmedia.xdme.com/tony/videos-book16/page-083.mp4 https://www.youtube.com/embed/t-9PwcO5gIg 115 2026-10-04T12:26:07+00:00 yes https://xdme.com/watch-book16-q084.html https://xdme.com/book16-thumbs/page-084.jpg Why Do Desert Bighorn Sheep Climb Steep Cliffs? Desert bighorn sheep climb steep cliffs because cliffs are their safest places! Hunters have trouble following across such steep ground. The sheep have hooves that are made for gri https://socialmedia.xdme.com/tony/videos-book16/page-084.mp4 https://www.youtube.com/embed/yIRoBKF5iDc 113 2026-10-04T12:29:18+00:00 yes https://xdme.com/watch-book16-q085.html https://xdme.com/book16-thumbs/page-085.jpg Why Can a Horned Lizard Look Like a Flat Rock? A horned lizard can look like a flat rock thanks to its flat body, its colors, and its spiky skin! That disguise helps it hide from hunters. It also has a few surprising tricks, li https://socialmedia.xdme.com/tony/videos-book16/page-085.mp4 https://www.youtube.com/embed/aGX6Il6zYKk 110 2026-10-04T12:32:21+00:00 yes https://xdme.com/watch-book16-q086.html https://xdme.com/book16-thumbs/page-086.jpg How Does the Tiny Elf Owl Find a Home in a Cactus? The tiny elf owl finds a home in a cactus by moving into a hole that a woodpecker made! The hole is cool, safe, and ready to use. Cactus and woodpecker work together to build a nes https://socialmedia.xdme.com/tony/videos-book16/page-086.mp4 https://www.youtube.com/embed/8S5Ir-LbXcY 110 2026-10-04T12:34:54+00:00 yes https://xdme.com/watch-book16-q087.html https://xdme.com/book16-thumbs/page-087.jpg Why Does the Sand Cat Have Furry Feet? The sand cat has furry feet to protect its paws from scorching and freezing sand! The fur also helps it grip loose sand, a bit like snowshoes in snow. And it hides the cat's footpr https://socialmedia.xdme.com/tony/videos-book16/page-087.mp4 https://www.youtube.com/embed/wDsQlOs_n14 110 2026-10-04T12:37:57+00:00 yes https://xdme.com/watch-book16-q088.html https://xdme.com/book16-thumbs/page-088.jpg Why Do Honeypot Ants Have Balloon-Shaped Bellies? Honeypot ants have balloon-shaped bellies because they are living storage jars! They hold sweet food for the whole colony. When food is scarce, their nest mates come to sip. https://socialmedia.xdme.com/tony/videos-book16/page-088.mp4 https://www.youtube.com/embed/mizQzmTdOw0 115 2026-10-04T12:40:59+00:00 yes https://xdme.com/watch-book16-q089.html https://xdme.com/book16-thumbs/page-089.jpg How Do Sandgrouse Carry Water to Their Chicks? Sandgrouse carry water to their chicks in their special belly feathers! The father soaks his belly feathers at a waterhole, and the mother helps look after the nest. Then he flies https://socialmedia.xdme.com/tony/videos-book16/page-089.mp4 https://www.youtube.com/embed/iY6wZqWVsLw 110 2026-10-04T12:51:02+00:00 yes https://xdme.com/watch-book16-q090.html https://xdme.com/book16-thumbs/page-090.jpg How Does the Sandfish Lizard Swim Through Sand? The sandfish lizard swims through sand by wiggling its smooth body like a fish! Its legs tuck against its sides, and its scales are very smooth. Underneath the sand, it stays cool https://socialmedia.xdme.com/tony/videos-book16/page-090.mp4 https://www.youtube.com/embed/vVNpPWdVCrk 112 2026-10-04T12:53:36+00:00 yes https://xdme.com/watch-book16-q091.html https://xdme.com/book16-thumbs/page-091.jpg Why Do Jerboas Hop on Two Long Legs? Jerboas hop on two long legs to dodge hunters and keep off the hot sand! They are small desert rodents with long back legs. Their long tail helps them balance, like a tightrope wal https://socialmedia.xdme.com/tony/videos-book16/page-091.mp4 https://www.youtube.com/embed/sL2S6LE5vTk 109 2026-10-04T12:56:41+00:00 yes https://xdme.com/watch-book16-q092.html https://xdme.com/book16-thumbs/page-092.jpg How Do Bats Help Desert Plants? Bats help desert plants by carrying pollen from flower to flower at night! The bats drink sweet nectar, and pollen from the flowers dusts their fur. That helps the plants make frui https://socialmedia.xdme.com/tony/videos-book16/page-092.mp4 https://www.youtube.com/embed/208IYOxN74k 114 2026-10-04T12:59:44+00:00 yes https://xdme.com/watch-book16-q093.html https://xdme.com/book16-thumbs/page-093.jpg Why Does the Bilby Dig So Many Burrows? A bilby digs many burrows to stay cool by day and safe from hunters! A bilby is a rabbit-sized animal from Australia. It uses different burrows in its home area. https://socialmedia.xdme.com/tony/videos-book16/page-093.mp4 https://www.youtube.com/embed/XPPWBsIMlBA 111 2026-10-04T13:02:17+00:00 yes https://xdme.com/watch-book16-q094.html https://xdme.com/book16-thumbs/page-094.jpg How Do Desert Elephants Live Where It Hardly Ever Rains? Desert elephants live where it hardly ever rains by walking far and digging for water! They remember where water can be found, even if it has been a long time. They also live in sm https://socialmedia.xdme.com/tony/videos-book16/page-094.mp4 https://www.youtube.com/embed/5ShC5ZIE-qo 115 2026-10-04T13:05:21+00:00 yes https://xdme.com/watch-book16-q095.html https://xdme.com/book16-thumbs/page-095.jpg How Do Desert Animals Keep Sand Out of Their Eyes and Noses? Desert animals keep sand out of their eyes and noses with built-in goggles and filters! Nature gave them special eyelids, eyelashes, and nostrils, all made for blowing sand. These https://socialmedia.xdme.com/tony/videos-book16/page-095.mp4 https://www.youtube.com/embed/UkzOzeUDUqg 117 2026-10-04T13:07:54+00:00 yes https://xdme.com/watch-book16-q096.html https://xdme.com/book16-thumbs/page-096.jpg How Do Scientists Find Out Which Animals Visit a Desert at Night? Scientists find out which animals visit a desert at night using camera traps and clues! They look for tracks, droppings, and burrows, and they record sounds. That way, shy animals https://socialmedia.xdme.com/tony/videos-book16/page-096.mp4 https://www.youtube.com/embed/0ojWLyj5zjw 115 2026-10-04T13:10:58+00:00 yes https://xdme.com/watch-book16-q097.html https://xdme.com/book16-thumbs/page-097.jpg How Can You Read Animal Tracks in the Sand? You can read animal tracks in the sand, because every track tells a story! The shape shows the animal's foot. The spacing shows how fast it moved. https://socialmedia.xdme.com/tony/videos-book16/page-097.mp4 https://www.youtube.com/embed/iIsK15VgDLM 109 2026-10-04T13:13:32+00:00 yes https://xdme.com/watch-book16-q098.html https://xdme.com/book16-thumbs/page-098.jpg Why Do Desert Geckos Have Such Big Eyes? Desert geckos have big eyes because they hunt at night and need to gather every bit of light! Their pupils open wide in the dark, to let in every bit of light. In daylight, they sh https://socialmedia.xdme.com/tony/videos-book16/page-098.mp4 https://www.youtube.com/embed/EUElZlU1W7w 112 2026-10-04T13:16:34+00:00 yes https://xdme.com/watch-book16-q099.html https://xdme.com/book16-thumbs/page-099.jpg Why Are Desert Tortoise Burrows Like Apartment Buildings? Desert tortoise burrows are like apartment buildings, because many animals move in! The burrow stays cool in summer and warm in winter, which is just right for a desert. Many guest https://socialmedia.xdme.com/tony/videos-book16/page-099.mp4 https://www.youtube.com/embed/Qb2TKxI8cu4 112 2026-10-04T13:19:08+00:00 yes https://xdme.com/watch-book16-q100.html https://xdme.com/book16-thumbs/page-100.jpg Who Eats What in a Desert Food Chain? A desert food chain shows who eats what, starting with plants! Plants use sunlight to make their own food, so they are called producers. Then animals pass that energy along when th https://socialmedia.xdme.com/tony/videos-book16/page-100.mp4 https://www.youtube.com/embed/mdbD9mzAe_U 111 2026-10-04T13:22:10+00:00 yes https://xdme.com/watch-book16-q101.html https://xdme.com/book16-thumbs/page-101.jpg Where Does an Oasis Get Its Water? An oasis gets its water from underground, and that water often began as rain or snow on faraway mountains! It soaks into the ground, travels slowly through rock, and comes up near https://socialmedia.xdme.com/tony/videos-book16/page-101.mp4 https://www.youtube.com/embed/YkZTncSYaHo 118 2026-10-04T13:25:14+00:00 yes https://xdme.com/watch-book16-q102.html https://xdme.com/book16-thumbs/page-102.jpg Why Can Palm Trees Grow at an Oasis? Date palms grow at an oasis because they love hot sunshine, but their roots also need lots of water! At an oasis, water is close to the surface, so the roots can drink. Palms do no https://socialmedia.xdme.com/tony/videos-book16/page-102.mp4 https://www.youtube.com/embed/3vOGuHwGdHE 114 2026-10-04T13:28:18+00:00 yes https://xdme.com/watch-book16-q103.html https://xdme.com/book16-thumbs/page-103.jpg What Is a Wadi? A wadi is a dry riverbed in a desert! In North America, people call it a wash or an arroyo. Most of the year it is only sand and gravel, but a storm can fill it with rushing water. https://socialmedia.xdme.com/tony/videos-book16/page-103.mp4 https://www.youtube.com/embed/bZY2HzV3OJQ 111 2026-10-04T13:30:51+00:00 yes https://xdme.com/watch-book16-q104.html https://xdme.com/book16-thumbs/page-104.jpg Why Can a Dry Riverbed Fill with Water on a Sunny Day? A dry riverbed can fill with water on a sunny day because a storm may be raining miles away! Water from that storm rushes downhill and arrives in a flash flood. People downstream m https://socialmedia.xdme.com/tony/videos-book16/page-104.mp4 https://www.youtube.com/embed/M2WyDdLtJe4 118 2026-10-04T13:33:53+00:00 yes https://xdme.com/watch-book16-q105.html https://xdme.com/book16-thumbs/page-105.jpg How Does Water Hide Underground in a Desert? Water hides underground in a desert by soaking into sand and rock, like water in a wet sponge! This hidden water is called groundwater. It can stay there for a very long time. https://socialmedia.xdme.com/tony/videos-book16/page-105.mp4 https://www.youtube.com/embed/zX55Imc0nxo 109 2026-10-04T13:36:56+00:00 yes https://xdme.com/watch-book16-q106.html https://xdme.com/book16-thumbs/page-106.jpg What Is Fossil Water, and Why Is It So Old? Fossil water is underground water that fell as rain a very long time ago! Under parts of the Sahara, some of it fell more than 20,000 years ago, when the climate was wetter. It sta https://socialmedia.xdme.com/tony/videos-book16/page-106.mp4 https://www.youtube.com/embed/oIgH_-EQKCE 112 2026-10-04T13:39:29+00:00 yes https://xdme.com/watch-book16-q107.html https://xdme.com/book16-thumbs/page-107.jpg How Does a Spring Flow Out of Dry Ground? A spring flows out of dry ground where underground water finds a way to the surface! It can come out through a crack in the rock, or where the land dips below the water level. In a https://socialmedia.xdme.com/tony/videos-book16/page-107.mp4 https://www.youtube.com/embed/outCqErLVkU 114 2026-10-04T13:42:32+00:00 yes https://xdme.com/watch-book16-q108.html https://xdme.com/book16-thumbs/page-108.jpg Why Do Tiny Fish Live in Only One Desert Pool? Tiny fish live in only one desert pool because they got trapped there as the land dried out! The Devils Hole pupfish lives in a single pool in a cave in the Nevada desert. That poo https://socialmedia.xdme.com/tony/videos-book16/page-108.mp4 https://www.youtube.com/embed/Bmb7XfoxJPE 110 2026-10-04T13:45:04+00:00 yes https://xdme.com/watch-book16-q109.html https://xdme.com/book16-thumbs/page-109.jpg Why Do Tiny Pools in Desert Rocks Teem with Life? Tiny pools in desert rocks teem with life because water is rare, so every pool is a busy spot! These rock hollows are called tinajas or potholes. They catch rain and can stay wet f https://socialmedia.xdme.com/tony/videos-book16/page-109.mp4 https://www.youtube.com/embed/qLjqXzZySGY 113 2026-10-04T13:48:08+00:00 yes https://xdme.com/watch-book16-q110.html https://xdme.com/book16-thumbs/page-110.jpg Why Does Fog Roll Into Some Coastal Deserts? Fog rolls into some coastal deserts because cold ocean water chills the air above it! Warm, moist air cools over the cold sea and turns into fog. Then the fog drifts onto the land. https://socialmedia.xdme.com/tony/videos-book16/page-110.mp4 https://www.youtube.com/embed/NkN4PeKMPeM 114 2026-10-04T13:51:17+00:00 yes https://xdme.com/watch-book16-q111.html https://xdme.com/book16-thumbs/page-111.jpg How Do Fog Nets Catch Water? Fog nets catch water by letting tiny fog droplets stick to a mesh! People stretch big nets across hilltops in dry places like the Atacama Desert. The droplets join together and tri https://socialmedia.xdme.com/tony/videos-book16/page-111.mp4 https://www.youtube.com/embed/sjIyCIU4kPI 114 2026-10-04T13:53:51+00:00 yes https://xdme.com/watch-book16-q112.html https://xdme.com/book16-thumbs/page-112.jpg Why Do Desert Rains Come in Short, Heavy Storms? Desert rains come in short, heavy storms because the hot ground makes warm air rise fast! The rising air cools, and a storm cloud forms quickly. Then it dumps its rain in a small a https://socialmedia.xdme.com/tony/videos-book16/page-112.mp4 https://www.youtube.com/embed/YejgG_0XnLM 111 2026-10-04T13:56:27+00:00 yes https://xdme.com/watch-book16-q113.html https://xdme.com/book16-thumbs/page-113.jpg Why Does Rain Sometimes Disappear Before It Hits the Ground? Rain sometimes disappears before it hits the ground because the air below the cloud is so dry! The falling drops evaporate on the way down. The water goes right back into the air. https://socialmedia.xdme.com/tony/videos-book16/page-113.mp4 https://www.youtube.com/embed/a6Yno09BFkY 110 2026-10-04T13:59:00+00:00 yes https://xdme.com/watch-book16-q114.html https://xdme.com/book16-thumbs/page-114.jpg Why Doesn’t Desert Soil Soak Up Rain Well? Desert soil does not soak up rain well because it is often baked hard or sealed by a thin crust! There are also few plant roots to open channels for water. So rain runs across the https://socialmedia.xdme.com/tony/videos-book16/page-114.mp4 https://www.youtube.com/embed/gIz917BPhUQ 111 2026-10-04T14:02:10+00:00 yes https://xdme.com/watch-book16-q115.html https://xdme.com/book16-thumbs/page-115.jpg What Is a Monsoon Season in a Desert? A monsoon season is a time of year when winds shift and bring moist air to a dry place! In parts of the southwestern United States and Mexico, it happens in summer. It brings thund https://socialmedia.xdme.com/tony/videos-book16/page-115.mp4 https://www.youtube.com/embed/53MGBYQPFi8 118 2026-10-04T14:04:43+00:00 yes https://xdme.com/watch-book16-q116.html https://xdme.com/book16-thumbs/page-116.jpg Why Can Desert Mornings Be Covered in Dew? Desert mornings can be covered in dew because cool nights turn invisible water vapor into droplets! Even in a desert, there is some water vapor in the air. When an object gets cold https://socialmedia.xdme.com/tony/videos-book16/page-116.mp4 https://www.youtube.com/embed/uI4x9hNFK6M 110 2026-10-04T14:07:16+00:00 yes https://xdme.com/watch-book16-q117.html https://xdme.com/book16-thumbs/page-117.jpg How Do Desert Animals Sense That Rain Is Coming? Desert animals sense that rain is coming by noticing clues that people often miss! Changes in the air, smells, and sounds can all signal a storm. Some animals even change what they https://socialmedia.xdme.com/tony/videos-book16/page-117.mp4 https://www.youtube.com/embed/zfTSQ7pNfro 111 2026-10-04T14:09:47+00:00 yes https://xdme.com/watch-book16-q118.html https://xdme.com/book16-thumbs/page-118.jpg Why Are Some Desert Lakes Saltier than the Ocean? Some desert lakes are saltier than the ocean because water can only leave them by evaporating! When the water evaporates, the salt stays behind. Over thousands of years, the lake g https://socialmedia.xdme.com/tony/videos-book16/page-118.mp4 https://www.youtube.com/embed/1ns_g0Bpok0 111 2026-10-04T14:12:53+00:00 yes https://xdme.com/watch-book16-q119.html https://xdme.com/book16-thumbs/page-119.jpg Why Do Some Desert Rivers Vanish Into the Sand? Some desert rivers vanish into the sand because they lose more water than they gain! Loose sand and gravel soak up the water, and the hot air makes the rest evaporate. The river sh https://socialmedia.xdme.com/tony/videos-book16/page-119.mp4 https://www.youtube.com/embed/dBjII1ojkSc 111 2026-10-04T14:15:37+00:00 yes https://xdme.com/watch-book16-q120.html https://xdme.com/book16-thumbs/page-120.jpg How Can a River Cross a Desert Without Drying Up? A river can cross a desert without drying up if it starts where lots of rain or snow falls! These rivers are so big that the desert cannot use up their water quickly. The Nile and https://socialmedia.xdme.com/tony/videos-book16/page-120.mp4 https://www.youtube.com/embed/W6KIU7QCRVM 106 2026-10-04T14:18:23+00:00 yes https://xdme.com/watch-book16-q121.html https://xdme.com/book16-thumbs/page-121.jpg How Can a Lake Appear in the Desert After a Big Rain? A lake can appear in the desert after a big rain because heavy rain fills dry basins with shallow water! These lakes are rare, and they do not last. When the water evaporates, the https://socialmedia.xdme.com/tony/videos-book16/page-121.mp4 https://www.youtube.com/embed/TfrdvcApEd0 110 2026-10-04T14:20:55+00:00 yes https://xdme.com/watch-book16-q122.html https://xdme.com/book16-thumbs/page-122.jpg How Do Scientists Find Water That Is Hidden Underground? Scientists find hidden water by combining many clues, like a team of detectives! They study rocks, drill test wells, and use tools that peek underground. They even use satellites i https://socialmedia.xdme.com/tony/videos-book16/page-122.mp4 https://www.youtube.com/embed/rMBHRMX3taM 115 2026-10-04T14:23:59+00:00 yes https://xdme.com/watch-book16-q123.html https://xdme.com/book16-thumbs/page-123.jpg Why Does Some Desert Water Taste Salty or Bitter? Some desert water tastes salty or bitter because it has dissolved minerals from the rocks around it! Water that sits in rock for a long time picks up salt. In dry places, evaporati https://socialmedia.xdme.com/tony/videos-book16/page-123.mp4 https://www.youtube.com/embed/qxkqR19Y97A 116 2026-10-04T14:26:32+00:00 yes https://xdme.com/watch-book16-q124.html https://xdme.com/book16-thumbs/page-124.jpg How Do Rocks Slide Across a Dry Lakebed? Rocks slide across a dry lakebed because of a clever team-up of water, thin ice, and wind! At Racetrack Playa in Death Valley, heavy rocks leave long trails across flat, cracked mu https://socialmedia.xdme.com/tony/videos-book16/page-124.mp4 https://www.youtube.com/embed/N2XglR_GtrE 114 2026-10-04T14:29:34+00:00 yes https://xdme.com/watch-book16-q125.html https://xdme.com/book16-thumbs/page-125.jpg How Can Old Lake Shorelines Show Up on Desert Mountainsides? Old lake shorelines show up on desert mountainsides because huge lakes once covered the land and then shrank! Waves carved level ledges into the mountains, like rings in a bathtub. https://socialmedia.xdme.com/tony/videos-book16/page-125.mp4 https://www.youtube.com/embed/_Obh_I1If0I 115 2026-10-04T14:32:07+00:00 yes https://xdme.com/watch-book16-q126.html https://xdme.com/book16-thumbs/page-126.jpg How Can Covering Up Keep You Cooler in a Hot Desert? Covering up can keep you cooler in a hot desert because loose clothes shade your skin from the Sun! The air trapped between the cloth and your skin helps keep heat off. That can fe https://socialmedia.xdme.com/tony/videos-book16/page-126.mp4 https://www.youtube.com/embed/xVgn6ckaRAQ 112 2026-10-04T14:35:10+00:00 yes https://xdme.com/watch-book16-q127.html https://xdme.com/book16-thumbs/page-127.jpg Why Are Many Desert Houses Made of Thick Mud Brick? Many desert houses are made of thick mud brick because thick walls heat up very slowly! Mud bricks are also called adobe. They keep the hot Sun out during the day. https://socialmedia.xdme.com/tony/videos-book16/page-127.mp4 https://www.youtube.com/embed/3goDJCUSmUU 111 2026-10-04T14:37:48+00:00 yes https://xdme.com/watch-book16-q128.html https://xdme.com/book16-thumbs/page-128.jpg How Do Tall Wind Towers Keep Desert Houses Cool? Tall wind towers keep desert houses cool by catching breezes and sending them down into the house! People in parts of Iran and the Middle East call them windcatchers. It is air con https://socialmedia.xdme.com/tony/videos-book16/page-128.mp4 https://www.youtube.com/embed/thiPqgC5LUQ 113 2026-10-04T14:40:21+00:00 yes https://xdme.com/watch-book16-q129.html https://xdme.com/book16-thumbs/page-129.jpg Why Are Old Desert Towns Built with Narrow, Winding Streets? Old desert towns have narrow, winding streets because narrow lanes stay shady and cool! Tall walls on both sides keep sunshine off the ground for most of the day. Wide, straight st https://socialmedia.xdme.com/tony/videos-book16/page-129.mp4 https://www.youtube.com/embed/6L-ANVc_NH8 115 2026-10-04T14:43:24+00:00 yes https://xdme.com/watch-book16-q130.html https://xdme.com/book16-thumbs/page-130.jpg What Is a Qanat, and How Does It Bring Water to a Village? A qanat is a long, gently sloping underground tunnel that brings water to a village. It starts at an aquifer in the foothills. Gravity does all the work, with no pumps! https://socialmedia.xdme.com/tony/videos-book16/page-130.mp4 https://www.youtube.com/embed/DXaw20a03m8 113 2026-10-04T14:45:56+00:00 yes https://xdme.com/watch-book16-q131.html https://xdme.com/book16-thumbs/page-131.jpg How Do Desert Farmers Grow Crops with So Little Water? Desert farmers grow crops with so little water by delivering it right where plants need it! The best-known trick is drip irrigation. It uses far less water than spraying. https://socialmedia.xdme.com/tony/videos-book16/page-131.mp4 https://www.youtube.com/embed/H4BaFdfUqrk 114 2026-10-04T14:48:29+00:00 yes https://xdme.com/watch-book16-q132.html https://xdme.com/book16-thumbs/page-132.jpg How Did Travelers Find Their Way Across the Desert Before Maps and GPS? Before maps and GPS, desert travelers found their way by reading the sky and the land! They followed the North Star at night and the Sun by day. They also remembered landmarks and https://socialmedia.xdme.com/tony/videos-book16/page-132.mp4 https://www.youtube.com/embed/rc0kS8XS4qQ 112 2026-10-04T14:51:32+00:00 yes https://xdme.com/watch-book16-q133.html https://xdme.com/book16-thumbs/page-133.jpg Why Are Deserts Such Good Places for Solar Panels? Deserts are great places for solar panels because they have strong sunshine, clear skies, and lots of open land! Solar panels turn light into electricity. A desert solar farm can h https://socialmedia.xdme.com/tony/videos-book16/page-133.mp4 https://www.youtube.com/embed/rqenAOuKQhU 112 2026-10-04T14:54:06+00:00 yes https://xdme.com/watch-book16-q134.html https://xdme.com/book16-thumbs/page-134.jpg How Do Mirror Fields in the Desert Turn Sunlight Into Electricity? Mirror fields turn sunlight into electricity by using heat to make steam! Hundreds or thousands of mirrors tilt to follow the Sun. They all bounce sunlight onto one spot at the top https://socialmedia.xdme.com/tony/videos-book16/page-134.mp4 https://www.youtube.com/embed/BE_jXhR6YTc 115 2026-10-04T14:57:08+00:00 yes https://xdme.com/watch-book16-q135.html https://xdme.com/book16-thumbs/page-135.jpg How Do Desert Cities Store Water for Dry Times? Desert cities store water for dry times by collecting it when it is available and saving it for later! They plan ahead so taps keep running, even in a dry year. Storing water is li https://socialmedia.xdme.com/tony/videos-book16/page-135.mp4 https://www.youtube.com/embed/0Fp5L7z8tTw 113 2026-10-04T15:00:00+00:00 yes https://xdme.com/watch-book16-q136.html https://xdme.com/book16-thumbs/page-136.jpg How Can Salty Water Be Turned Into Fresh Water? Salty water can be turned into fresh water by taking the salt out in a process called desalination! One way uses heat, and another uses super-fine filters. Both leave the salt behi https://socialmedia.xdme.com/tony/videos-book16/page-136.mp4 https://www.youtube.com/embed/C8ySsfro8qc 112 2026-10-04T15:02:02+00:00 yes https://xdme.com/watch-book16-q137.html https://xdme.com/book16-thumbs/page-137.jpg What Is Desertification? Desertification is when land that was once green becomes dry and desert-like. Long droughts and careless use of the land can strip away the plants that hold soil in place. Then the https://socialmedia.xdme.com/tony/videos-book16/page-137.mp4 https://www.youtube.com/embed/R6UNsUOy-To 113 2026-10-04T15:05:06+00:00 yes https://xdme.com/watch-book16-q138.html https://xdme.com/book16-thumbs/page-138.jpg What Helps Hold Sand Dunes in Place Near Farms and Roads? People hold sand dunes in place near farms and roads using plants, fences, and windbreaks! Grasses, shrubs, and trees have roots that grip the sand. Fences slow the wind so it drop https://socialmedia.xdme.com/tony/videos-book16/page-138.mp4 https://www.youtube.com/embed/pgNmD6lc5dU 115 2026-10-04T15:07:49+00:00 yes https://xdme.com/watch-book16-q139.html https://xdme.com/book16-thumbs/page-139.jpg What Is the Crust on Desert Soil, and Why Shouldn’t You Step on It? The crust on desert soil is a living skin made of tiny living things! Because it is alive and fragile, you should never step on it. Rangers say, don't bust the crust! https://socialmedia.xdme.com/tony/videos-book16/page-139.mp4 https://www.youtube.com/embed/l46adS8iq2o 110 2026-10-04T15:10:22+00:00 yes https://xdme.com/watch-book16-q140.html https://xdme.com/book16-thumbs/page-140.jpg Why Do Rangers Ask Hikers to Stay on the Trail? Rangers ask hikers to stay on the trail to protect the desert and to keep hikers safe! Desert plants grow slowly, and animals nest in hidden places. Staying on the path lets the de https://socialmedia.xdme.com/tony/videos-book16/page-140.mp4 https://www.youtube.com/embed/z-wJDEQfsf0 111 2026-10-04T15:13:05+00:00 yes https://xdme.com/watch-book16-q141.html https://xdme.com/book16-thumbs/page-141.jpg Why Do Paleontologists Love Deserts and Badlands? Paleontologists love deserts and badlands because old bones and fossils are easy to find there! Few plants cover the ground, and wind and rain quickly wear away soil. That exposes https://socialmedia.xdme.com/tony/videos-book16/page-141.mp4 https://www.youtube.com/embed/K8yZZ5Z_VEg 116 2026-10-04T15:15:43+00:00 yes https://xdme.com/watch-book16-q142.html https://xdme.com/book16-thumbs/page-142.jpg Why Do Dry Places Keep Old Things From Rotting? Dry places keep old things from rotting because rot needs moisture! Fungi and bacteria that cause rot cannot grow well without water. So in dry deserts, old things can last for a v https://socialmedia.xdme.com/tony/videos-book16/page-142.mp4 https://www.youtube.com/embed/obJxmPh6a2E 113 2026-10-04T15:18:18+00:00 yes https://xdme.com/watch-book16-q143.html https://xdme.com/book16-thumbs/page-143.jpg What Jobs Involve Studying Deserts? Many jobs involve studying deserts, from scientists who study life to rangers who care for the land! Each job asks a different kind of question about the same dry, amazing land. To https://socialmedia.xdme.com/tony/videos-book16/page-143.mp4 https://www.youtube.com/embed/2NytTdvntkA 118 2026-10-04T15:21:21+00:00 yes https://xdme.com/watch-book16-q144.html https://xdme.com/book16-thumbs/page-144.jpg What Do Scientists Pack for a Day of Fieldwork in a Desert? Scientists pack carefully for a day of desert fieldwork, because planning keeps them safe! They bring lots of water, sun protection, and safety gear. And they never go alone. https://socialmedia.xdme.com/tony/videos-book16/page-144.mp4 https://www.youtube.com/embed/Zy3ln09AV1s 108 2026-10-04T15:23:53+00:00 yes https://xdme.com/watch-book16-q145.html https://xdme.com/book16-thumbs/page-145.jpg How Can You Stay Safe on a Desert Hike? You can stay safe on a desert hike by planning ahead, going with a grown-up, and respecting the heat! Heat is the main danger in the desert. A hat and a full water bottle are a hik https://socialmedia.xdme.com/tony/videos-book16/page-145.mp4 https://www.youtube.com/embed/4kVf3_6xH0w 108 2026-10-04T15:26:27+00:00 yes https://xdme.com/watch-book16-q146.html https://xdme.com/book16-thumbs/page-146.jpg What Should You Do If You See a Snake or Scorpion Outdoors? If you see a snake or scorpion outdoors, stay calm, back away slowly, and tell a grown-up right away! Most wild animals do not want to bother people. They will go away if left alon https://socialmedia.xdme.com/tony/videos-book16/page-146.mp4 https://www.youtube.com/embed/IHwDPG4V8eE 109 2026-10-04T15:29:31+00:00 yes https://xdme.com/watch-book16-q147.html https://xdme.com/book16-thumbs/page-147.jpg Why Do Some Desert Animals Need People’s Help to Survive? Some desert animals need people's help because they live where water and food are scarce! That means even small changes can matter a lot. People can protect them in many ways. https://socialmedia.xdme.com/tony/videos-book16/page-147.mp4 https://www.youtube.com/embed/LO4_2zKnh6E 117 2026-10-04T15:32:04+00:00 yes https://xdme.com/watch-book16-q148.html https://xdme.com/book16-thumbs/page-148.jpg How Can Kids Help Save Water at Home? Kids can help save water at home with small habits that add up! Saving water matters in deserts and in every community, because fresh water is precious everywhere. Even a little ch https://socialmedia.xdme.com/tony/videos-book16/page-148.mp4 https://www.youtube.com/embed/xG8KeKfxPpw 109 2026-10-04T15:35:07+00:00 yes https://xdme.com/watch-book16-q149.html https://xdme.com/book16-thumbs/page-149.jpg Why Can the Desert Feel So Quiet? The desert can feel so quiet because few things make noise there, especially during the day! There are few leaves to rustle and few running streams. Many animals sleep in burrows t https://socialmedia.xdme.com/tony/videos-book16/page-149.mp4 https://www.youtube.com/embed/7x9Nb2PKV9Y 112 2026-10-04T15:37:40+00:00 yes https://xdme.com/watch-book16-q150.html https://xdme.com/book16-thumbs/page-150.jpg What Mysteries About Deserts Are Still Unsolved? Scientists still have lots to learn about deserts, and that is what makes them exciting! There are big mysteries about microbes, water, climate, and plants, even today. Every answe https://socialmedia.xdme.com/tony/videos-book16/page-150.mp4 https://www.youtube.com/embed/HLEgYFrY2uA 114 2026-10-04T15:40:45+00:00 yes https://xdme.com/watch-book17-q001.html https://xdme.com/book17-thumbs/page-001.jpg What Is a Rainforest, and Where in the World Are Rainforests Found? A rainforest is a thick, green forest that gets a great deal of rain, usually more than 80 inches a year! Most are tropical, growing in a warm belt around the middle of the Earth. https://socialmedia.xdme.com/tony/videos-book17/page-001.mp4 https://www.youtube.com/embed/Js0uVw0d_2Y 124 2026-10-04T16:10:52+00:00 yes https://xdme.com/watch-book17-q002.html https://xdme.com/book17-thumbs/page-002.jpg How Is a Tropical Rainforest Different From a Temperate Rainforest? A tropical rainforest is hot and wet all year, near the equator. A temperate rainforest is cooler, and grows near the ocean where rain and fog roll in. Both are rainy forests, but https://socialmedia.xdme.com/tony/videos-book17/page-002.mp4 https://www.youtube.com/embed/hKnyqHod_Sk 120 2026-10-04T16:10:54+00:00 yes https://xdme.com/watch-book17-q003.html https://xdme.com/book17-thumbs/page-003.jpg Why Do Tropical Rainforests Grow in a Belt Around the Middle of the Earth? Near the equator, the Sun shines almost straight down all year long. That keeps the land and sea warm, and warm air makes lots of rain. With warmth, rain, and sunlight, plants can https://socialmedia.xdme.com/tony/videos-book17/page-003.mp4 https://www.youtube.com/embed/mQl2uYpjaVA 115 2026-10-04T16:10:55+00:00 yes https://xdme.com/watch-book17-q004.html https://xdme.com/book17-thumbs/page-004.jpg What Are the Four Layers of a Rainforest? A rainforest has four layers, like floors in a tall building. From top to bottom they are the emergent layer, the canopy, the understory, and the forest floor. Each layer has its o https://socialmedia.xdme.com/tony/videos-book17/page-004.mp4 https://www.youtube.com/embed/HEEgSeVHm7A 114 2026-10-04T16:10:56+00:00 yes https://xdme.com/watch-book17-q005.html https://xdme.com/book17-thumbs/page-005.jpg Why Do a Few Rainforest Trees Poke Up Above All the Others? Trees in the emergent layer stretch up 150 feet or more, which is 45 meters, to catch the brightest sunlight. They also catch the breeze that carries their pollen and seeds. A gap https://socialmedia.xdme.com/tony/videos-book17/page-005.mp4 https://www.youtube.com/embed/qGhnuwdZaP0 110 2026-10-04T16:10:58+00:00 yes https://xdme.com/watch-book17-q006.html https://xdme.com/book17-thumbs/page-006.jpg Why Is the Canopy Called the Roof of the Forest? The canopy is the thick layer where the branches and leaves of most tall trees meet. It is about 60 to 100 feet up, which is 18 to 30 meters. It catches most of the sunlight and ra https://socialmedia.xdme.com/tony/videos-book17/page-006.mp4 https://www.youtube.com/embed/R-aynpQ4maM 113 2026-10-04T16:12:23+00:00 yes https://xdme.com/watch-book17-q007.html https://xdme.com/book17-thumbs/page-007.jpg What Is the Understory, and Why Is It So Still and Shady? The understory is the layer under the canopy where young trees, shrubs, and ferns grow. Only a small amount of sunlight filters down, and the canopy blocks the wind. That makes the https://socialmedia.xdme.com/tony/videos-book17/page-007.mp4 https://www.youtube.com/embed/aLe37Wf5ySA 112 2026-10-04T16:14:56+00:00 yes https://xdme.com/watch-book17-q008.html https://xdme.com/book17-thumbs/page-008.jpg Why Is the Rainforest Floor So Dark? The thick canopy and understory catch most of the sunlight before it reaches the ground. In some rainforests, only about 2 percent of the light makes it to the floor. That is why t https://socialmedia.xdme.com/tony/videos-book17/page-008.mp4 https://www.youtube.com/embed/hdp7dw4YSMI 111 2026-10-04T16:17:29+00:00 yes https://xdme.com/watch-book17-q009.html https://xdme.com/book17-thumbs/page-009.jpg Why Are So Many Rainforest Trees Tall and Skinny with No Branches Near the Ground? Rainforest trees race one another for sunlight. A tall trunk with no low branches grows fast toward the light. It saves energy by not growing leaves where it is dark, and spreads i https://socialmedia.xdme.com/tony/videos-book17/page-009.mp4 https://www.youtube.com/embed/HBvjA4ZSeFU 112 2026-10-04T16:21:02+00:00 yes https://xdme.com/watch-book17-q010.html https://xdme.com/book17-thumbs/page-010.jpg How Tall Can a Rainforest Tree Grow? Some tropical trees grow more than 200 feet tall, which is 60 meters and taller than a 20-story building. In Borneo, scientists have measured trees almost 330 feet tall. Growing so https://socialmedia.xdme.com/tony/videos-book17/page-010.mp4 https://www.youtube.com/embed/rM7B3KltrbU 112 2026-10-04T16:24:07+00:00 yes https://xdme.com/watch-book17-q011.html https://xdme.com/book17-thumbs/page-011.jpg Why Does the Air Under the Trees Feel Like a Warm, Wet Blanket? Trees release water vapor from their leaves, and the thick canopy traps that moisture and keeps the wind out. So the air near the ground can be nearly 100 percent humid. It feels l https://socialmedia.xdme.com/tony/videos-book17/page-011.mp4 https://www.youtube.com/embed/Vpps8eL-6-M 109 2026-10-04T16:26:38+00:00 yes https://xdme.com/watch-book17-q012.html https://xdme.com/book17-thumbs/page-012.jpg Why Does the Temperature Stay Almost the Same All Year in a Rainforest? Near the equator, the Sun's strength barely changes through the year, so every month is warm. Clouds and the thick canopy also keep days from getting scorching and nights from gett https://socialmedia.xdme.com/tony/videos-book17/page-012.mp4 https://www.youtube.com/embed/KWWJbDA2I4U 118 2026-10-04T16:29:43+00:00 yes https://xdme.com/watch-book17-q013.html https://xdme.com/book17-thumbs/page-013.jpg How Many Kinds of Living Things Live in a Rainforest? Rainforests hold more kinds of plants and animals than any other land habitat. They cover only about 6 percent of Earth's land, yet by many estimates they are home to more than hal https://socialmedia.xdme.com/tony/videos-book17/page-013.mp4 https://www.youtube.com/embed/wABcwVHY9wo 117 2026-10-04T16:32:15+00:00 yes https://xdme.com/watch-book17-q014.html https://xdme.com/book17-thumbs/page-014.jpg Why Can a Small Patch of Rainforest Hold Hundreds of Kinds of Trees? In many forests, a few kinds of trees dominate. In a rainforest, each kind of tree is rare, so a small patch may have hundreds of different trees with only a few of each. Scientist https://socialmedia.xdme.com/tony/videos-book17/page-014.mp4 https://www.youtube.com/embed/YIM9-00uBpw 115 2026-10-04T16:34:48+00:00 yes https://xdme.com/watch-book17-q015.html https://xdme.com/book17-thumbs/page-015.jpg Why Is a Rainforest So Loud? A rainforest is packed with animals that call, buzz, and chirp. Frogs sing, insects click and hum, birds shout, and monkeys howl. Together they make a huge, noisy choir! https://socialmedia.xdme.com/tony/videos-book17/page-015.mp4 https://www.youtube.com/embed/0jdruCFpZAI 115 2026-10-04T16:37:51+00:00 yes https://xdme.com/watch-book17-q016.html https://xdme.com/book17-thumbs/page-016.jpg Why Does the Rainforest Smell Earthy and a Little Sweet? The rainforest smell comes from busy recycling. Fallen leaves, wood, and fruit are broken down by fungi and bacteria, which release smelly gases. Flowers and fruit add sweet smells https://socialmedia.xdme.com/tony/videos-book17/page-016.mp4 https://www.youtube.com/embed/aVg0To2HcBc 114 2026-10-04T16:40:24+00:00 yes https://xdme.com/watch-book17-q017.html https://xdme.com/book17-thumbs/page-017.jpg Are Rainforests Really the Lungs of the Earth? You may have heard that rainforests are the lungs of the Earth, but that saying is mostly a myth. Rainforest plants do make lots of oxygen, but the forest's animals, fungi, and bac https://socialmedia.xdme.com/tony/videos-book17/page-017.mp4 https://www.youtube.com/embed/K9ZFw5lKABY 116 2026-10-04T16:43:32+00:00 yes https://xdme.com/watch-book17-q018.html https://xdme.com/book17-thumbs/page-018.jpg Why Are There So Many Insects in Rainforests? Warm, wet weather all year means insects never have to sleep through a winter. There are plenty of leaves, flowers, wood, and fruit to eat, plus countless hiding places. That is wh https://socialmedia.xdme.com/tony/videos-book17/page-018.mp4 https://www.youtube.com/embed/2VRdXzJalTE 115 2026-10-04T16:46:04+00:00 yes https://xdme.com/watch-book17-q019.html https://xdme.com/book17-thumbs/page-019.jpg How Do So Many Animals Share One Rainforest Without Crowding Each Other Out? Each kind of animal has its own job, food, and place to live. Scientists call this a niche. One bird eats fruit in the canopy while another snaps up insects on the forest floor. https://socialmedia.xdme.com/tony/videos-book17/page-019.mp4 https://www.youtube.com/embed/TALkr3hUxLU 111 2026-10-04T16:48:37+00:00 yes https://xdme.com/watch-book17-q020.html https://xdme.com/book17-thumbs/page-020.jpg What Is a Cloud Forest? A cloud forest grows high on a tropical mountain, where clouds drift right through the trees. The air is cool, damp, and misty all day long. The trees are covered with moss, ferns, https://socialmedia.xdme.com/tony/videos-book17/page-020.mp4 https://www.youtube.com/embed/_bIul_VCFVM 114 2026-10-04T16:51:17+00:00 yes https://xdme.com/watch-book17-q021.html https://xdme.com/book17-thumbs/page-021.jpg What Lives in a Temperate Rainforest on the Pacific Coast? The Pacific coast has huge trees like western red cedar, Sitka spruce, and western hemlock, along with ferns and thick moss. Black bears, wolves, bald eagles, and salmon live there https://socialmedia.xdme.com/tony/videos-book17/page-021.mp4 https://www.youtube.com/embed/1E7BDMIVa90 116 2026-10-04T16:54:03+00:00 yes https://xdme.com/watch-book17-q022.html https://xdme.com/book17-thumbs/page-022.jpg Why Are Temperate Rainforests Covered in Moss? Moss loves damp, cool, shady places, and temperate rainforests have plenty of all three. Moss has no roots to take up water, so it soaks it up straight from the air and rain. It ca https://socialmedia.xdme.com/tony/videos-book17/page-022.mp4 https://www.youtube.com/embed/2AqJo0y9_eg 112 2026-10-04T16:57:07+00:00 yes https://xdme.com/watch-book17-q023.html https://xdme.com/book17-thumbs/page-023.jpg Why Do Some Rainforests Flood for Part of the Year? In the Amazon basin, heavy rains and melting snow far away make rivers rise as much as 30 or 40 feet for months. The water spreads into the forest, creating a flooded forest. Trees https://socialmedia.xdme.com/tony/videos-book17/page-023.mp4 https://www.youtube.com/embed/57KPYqSDXW4 110 2026-10-04T16:59:41+00:00 yes https://xdme.com/watch-book17-q024.html https://xdme.com/book17-thumbs/page-024.jpg Where Are the Biggest Rainforests on Earth? The Amazon in South America is the largest rainforest on Earth. It covers an area about two thirds as big as the lower 48 United States. The Congo Basin in Africa is second. https://socialmedia.xdme.com/tony/videos-book17/page-024.mp4 https://www.youtube.com/embed/ELPnxwMUsg8 117 2026-10-04T17:02:44+00:00 yes https://xdme.com/watch-book17-q025.html https://xdme.com/book17-thumbs/page-025.jpg How Old Are Rainforests? Some rainforests are among the oldest living ecosystems on Earth. The Daintree Rainforest in Australia is estimated to be about 180 million years old. That is older than the Amazon https://socialmedia.xdme.com/tony/videos-book17/page-025.mp4 https://www.youtube.com/embed/TCDK5A3uzJs 119 2026-10-04T17:05:17+00:00 yes https://xdme.com/watch-book17-q026.html https://xdme.com/book17-thumbs/page-026.jpg What Happens to a Raindrop on Its Way Down Through the Forest? A raindrop hits the canopy first. Some drops cling to leaves and evaporate straight back into the air, while others drip from leaf to leaf or run down branches and trunks. So a rai https://socialmedia.xdme.com/tony/videos-book17/page-026.mp4 https://www.youtube.com/embed/1c_z6z_2NYQ 117 2026-10-04T17:07:50+00:00 yes https://xdme.com/watch-book17-q027.html https://xdme.com/book17-thumbs/page-027.jpg Why Does It Rain Almost Every Afternoon in Some Rainforests? In some rainforests, it rains almost every afternoon like clockwork! In the morning, the Sun heats the forest and water evaporates into the air. By afternoon, that warm, wet air ha https://socialmedia.xdme.com/tony/videos-book17/page-027.mp4 https://www.youtube.com/embed/cxuPBnqFBVo 117 2026-10-04T17:11:17+00:00 yes https://xdme.com/watch-book17-q028.html https://xdme.com/book17-thumbs/page-028.jpg How Does a Rainforest Help Make Its Own Rain? Trees pull water from the soil and release it as vapor through tiny pores in their leaves. This is called transpiration. Millions of trees add huge amounts of moisture to the air. https://socialmedia.xdme.com/tony/videos-book17/page-028.mp4 https://www.youtube.com/embed/GjmM8ANQpLc 117 2026-10-04T17:13:50+00:00 yes https://xdme.com/watch-book17-q029.html https://xdme.com/book17-thumbs/page-029.jpg What Are the Flying Rivers of the Amazon? Flying rivers are streams of water vapor that flow through the air above the rainforest, carried by winds. They bring moisture from the Atlantic Ocean across the forest, and the tr https://socialmedia.xdme.com/tony/videos-book17/page-029.mp4 https://www.youtube.com/embed/Itd8ihJdypw 113 2026-10-04T17:16:22+00:00 yes https://xdme.com/watch-book17-q030.html https://xdme.com/book17-thumbs/page-030.jpg Why Does Mist Rise From the Forest After a Storm? After a storm, the leaves, branches, and ground are warm and wet. When the Sun comes out, water evaporates into the cooler air above. The vapor turns into tiny droplets you can see https://socialmedia.xdme.com/tony/videos-book17/page-030.mp4 https://www.youtube.com/embed/92vOjUrKl4I 110 2026-10-04T17:18:57+00:00 yes https://xdme.com/watch-book17-q031.html https://xdme.com/book17-thumbs/page-031.jpg Why Is Rainforest Soil Poor Even Though Plants Grow So Thickly? Rainforest soils are old, and heavy rain keeps washing the nutrients down and away. Most nutrients are locked inside living plants and fresh leaf litter. So the forest feeds itself https://socialmedia.xdme.com/tony/videos-book17/page-031.mp4 https://www.youtube.com/embed/r-_mpvp-BTw 116 2026-10-04T17:22:29+00:00 yes https://xdme.com/watch-book17-q032.html https://xdme.com/book17-thumbs/page-032.jpg How Can Giant Trees Grow in Poor Soil? Most rainforest trees have shallow, wide roots that spread through the top few inches of soil. That is where fallen leaves rot and release nutrients. Helpful fungi on the roots hel https://socialmedia.xdme.com/tony/videos-book17/page-032.mp4 https://www.youtube.com/embed/gw00k_L2-Zg 111 2026-10-04T17:25:03+00:00 yes https://xdme.com/watch-book17-q033.html https://xdme.com/book17-thumbs/page-033.jpg Why Does a Fallen Leaf Disappear in Just a Few Weeks? In the warm, wet air of the rainforest, decomposers work very quickly. Fungi, bacteria, termites, and other tiny animals break down dead leaves into simple nutrients that plants ca https://socialmedia.xdme.com/tony/videos-book17/page-033.mp4 https://www.youtube.com/embed/aqaluo6sVmE 117 2026-10-04T17:28:06+00:00 yes https://xdme.com/watch-book17-q034.html https://xdme.com/book17-thumbs/page-034.jpg Why Do Mushrooms and Other Fungi Love the Forest Floor? Fungi are the forest's recyclers. They grow long, thread-like strands through dead leaves and wood, digesting them from the outside. What you see as a mushroom is only the fruiting https://socialmedia.xdme.com/tony/videos-book17/page-034.mp4 https://www.youtube.com/embed/OWl_J6LIVFI 114 2026-10-04T17:30:39+00:00 yes https://xdme.com/watch-book17-q035.html https://xdme.com/book17-thumbs/page-035.jpg Why Are Termites and Beetles Good for a Forest? Termites and wood-boring beetles chew dead trees into small pieces. Inside termites' guts live tiny microbes that digest wood. Together they are small but vital recyclers. https://socialmedia.xdme.com/tony/videos-book17/page-035.mp4 https://www.youtube.com/embed/yYHpS54PowU 114 2026-10-04T17:33:13+00:00 yes https://xdme.com/watch-book17-q036.html https://xdme.com/book17-thumbs/page-036.jpg What Happens When a Giant Tree Falls in a Rainforest? A falling tree can drag down vines and smaller trees, opening a gap in the canopy. Sunlight pours in, and seedlings that had been waiting in the shade race upward. Within a few yea https://socialmedia.xdme.com/tony/videos-book17/page-036.mp4 https://www.youtube.com/embed/Um8IxhgdvGg 112 2026-10-04T17:36:16+00:00 yes https://xdme.com/watch-book17-q037.html https://xdme.com/book17-thumbs/page-037.jpg Why Do Tiny Seedlings Wait in the Shade for Years? Seedlings that start in the dark can't grow much, so they stay small and grow very slowly. Sometimes they wait for decades, saving their energy. When a tree falls and opens a gap, https://socialmedia.xdme.com/tony/videos-book17/page-037.mp4 https://www.youtube.com/embed/EU4ql6trykc 111 2026-10-04T17:38:48+00:00 yes https://xdme.com/watch-book17-q038.html https://xdme.com/book17-thumbs/page-038.jpg Why Can a Tropical Sapling Shoot Up So Quickly? Plants need sunlight, water, and warmth, and a rainforest has all three nearly all year. There is no winter to stop growth, so plants can keep making leaves, wood, and fruit. Some https://socialmedia.xdme.com/tony/videos-book17/page-038.mp4 https://www.youtube.com/embed/uiCJOQMeJBk 115 2026-10-04T17:41:21+00:00 yes https://xdme.com/watch-book17-q039.html https://xdme.com/book17-thumbs/page-039.jpg How Do Rainforest Trees Soak Up Carbon Dioxide and Store It? Leaves take in carbon dioxide from the air. With sunlight and water, they use it to make sugars. The tree uses that carbon to build wood, leaves, and roots. https://socialmedia.xdme.com/tony/videos-book17/page-039.mp4 https://www.youtube.com/embed/HcRkUdGlbCs 111 2026-10-04T17:44:24+00:00 yes https://xdme.com/watch-book17-q040.html https://xdme.com/book17-thumbs/page-040.jpg Why Is the Rio Negro Black Like Tea? The Rio Negro, a big river in the Amazon, gets its dark color from natural chemicals that seep out of rotting leaves and roots. It works just like tea coloring water. The water is https://socialmedia.xdme.com/tony/videos-book17/page-040.mp4 https://www.youtube.com/embed/3MLzuudFnXQ 116 2026-10-04T17:47:01+00:00 yes https://xdme.com/watch-book17-q041.html https://xdme.com/book17-thumbs/page-041.jpg Where Do Animals Shelter When It Pours in the Rainforest? When it pours in the rainforest, many animals tuck under large leaves, crawl into tree holes, or burrow into the ground. Birds sit close to the trunk or under thick leaves, and but https://socialmedia.xdme.com/tony/videos-book17/page-041.mp4 https://www.youtube.com/embed/6yEiky5q1l4 112 2026-10-04T17:50:04+00:00 yes https://xdme.com/watch-book17-q042.html https://xdme.com/book17-thumbs/page-042.jpg What Are Sunflecks, and How Do Small Plants Use Them? Sunflecks are small patches of sunlight that slip through gaps in the canopy and move across the forest floor. They last only seconds or minutes. For small plants, they can provide https://socialmedia.xdme.com/tony/videos-book17/page-042.mp4 https://www.youtube.com/embed/i-5SoT20WjY 110 2026-10-04T17:52:44+00:00 yes https://xdme.com/watch-book17-q043.html https://xdme.com/book17-thumbs/page-043.jpg How Do Scientists Measure the Weather Inside a Rainforest? Scientists set up tall towers topped with instruments, plus rain gauges and sensors on the forest floor. They measure temperature, humidity, wind, and the gases trees breathe in an https://socialmedia.xdme.com/tony/videos-book17/page-043.mp4 https://www.youtube.com/embed/Ze6qvrYiPDs 115 2026-10-04T17:55:19+00:00 yes https://xdme.com/watch-book17-q044.html https://xdme.com/book17-thumbs/page-044.jpg Why Do Some Tropical Forests Drop Their Leaves in the Dry Season? Not all tropical forests are wet all year. In places with a long dry season, many trees shed their leaves to save water. Then they grow new ones when the rains return. https://socialmedia.xdme.com/tony/videos-book17/page-044.mp4 https://www.youtube.com/embed/1uXg164OEhM 113 2026-10-04T17:57:52+00:00 yes https://xdme.com/watch-book17-q045.html https://xdme.com/book17-thumbs/page-045.jpg What Does a Rainforest Look Like From Space? From space, the Amazon looks like a deep green blanket crossed by winding brown rivers. Towering clouds often rise above it in the afternoon. Satellites help scientists keep track https://socialmedia.xdme.com/tony/videos-book17/page-045.mp4 https://www.youtube.com/embed/H5CkmNGgWIU 113 2026-10-04T18:00:55+00:00 yes https://xdme.com/watch-book17-q046.html https://xdme.com/book17-thumbs/page-046.jpg What Is the Difference Between a Rainforest and a Jungle? A rainforest is a tall forest with a thick canopy, and most of its floor is shady and fairly open. A jungle is a tangled, thick growth of plants, often found at forest edges, along https://socialmedia.xdme.com/tony/videos-book17/page-046.mp4 https://www.youtube.com/embed/bZ76ZgU9L9o 117 2026-10-04T18:03:58+00:00 yes https://xdme.com/watch-book17-q047.html https://xdme.com/book17-thumbs/page-047.jpg What Is Humus, and Why Is the Layer of Good Soil So Thin in a Rainforest? Humus is dark, crumbly material made from rotted plants and animals. It stores nutrients and water for plant roots. In the rainforest, little humus builds up, so the rich soil laye https://socialmedia.xdme.com/tony/videos-book17/page-047.mp4 https://www.youtube.com/embed/b3PvMqxkiCQ 114 2026-10-04T18:07:01+00:00 yes https://xdme.com/watch-book17-q048.html https://xdme.com/book17-thumbs/page-048.jpg How Does a Forest Heal Itself After a Storm or Landslide? After a storm or landslide, fast-growing pioneer plants, such as Cecropia trees and ferns, spring up in the open light. They shade the soil and make it better for others. Slower, b https://socialmedia.xdme.com/tony/videos-book17/page-048.mp4 https://www.youtube.com/embed/6KV7HXHh8ig 118 2026-10-04T18:09:38+00:00 yes https://xdme.com/watch-book17-q049.html https://xdme.com/book17-thumbs/page-049.jpg Can a Rainforest Change the Weather Far Away? Yes! Scientists have found that moisture released by the Amazon travels with the wind. It falls as rain in other parts of South America, including farmland far to the south. https://socialmedia.xdme.com/tony/videos-book17/page-049.mp4 https://www.youtube.com/embed/JNdlsnCCqQg 113 2026-10-04T18:12:20+00:00 yes https://xdme.com/watch-book17-q050.html https://xdme.com/book17-thumbs/page-050.jpg How Do Insects and Frogs Take Advantage of the Rainy Season? When the rains arrive, many frogs gather at fresh pools and breed. Insects also emerge in huge numbers, because fresh leaves and puddles provide food and places for eggs and young. https://socialmedia.xdme.com/tony/videos-book17/page-050.mp4 https://www.youtube.com/embed/AYdZEuAXwHg 116 2026-10-04T18:15:23+00:00 yes https://xdme.com/watch-book17-q051.html https://xdme.com/book17-thumbs/page-051.jpg How Do Monkeys Swing and Leap From Branch to Branch? Monkeys and apes swing and leap using strong arms, grippy hands, and clever balance! Gibbons swing hand over hand, and many monkeys jump between branches. Each way of moving fits t https://socialmedia.xdme.com/tony/videos-book17/page-051.mp4 https://www.youtube.com/embed/PeywKd6xyhQ 120 2026-10-04T18:18:26+00:00 yes https://xdme.com/watch-book17-q052.html https://xdme.com/book17-thumbs/page-052.jpg Why Do Some Monkeys Have Tails That Can Grab Like a Hand? Some monkeys have tails that grip like an extra hand! Spider monkeys and howler monkeys have grabbing tails, which scientists call prehensile. The tail holds on while the monkey re https://socialmedia.xdme.com/tony/videos-book17/page-052.mp4 https://www.youtube.com/embed/zX8rXUcnHRE 116 2026-10-04T18:21:28+00:00 yes https://xdme.com/watch-book17-q053.html https://xdme.com/book17-thumbs/page-053.jpg How Do Animals Glide From Tree to Tree? Some rainforest animals cannot fly, but they can glide! They spread out skin, ribs, or feet like a parachute and sail from tree to tree. Gliding saves energy and keeps them away fr https://socialmedia.xdme.com/tony/videos-book17/page-053.mp4 https://www.youtube.com/embed/2GfYvyN2gAc 115 2026-10-04T18:24:01+00:00 yes https://xdme.com/watch-book17-q054.html https://xdme.com/book17-thumbs/page-054.jpg How Do Tree Frogs Stick to Leaves? Tree frogs have sticky toe pads that cling to leaves, even wet, upside-down ones! The pads are covered in tiny bumps and a thin layer of slippery liquid. Together they make a grip https://socialmedia.xdme.com/tony/videos-book17/page-054.mp4 https://www.youtube.com/embed/00X7DzblFmc 116 2026-10-04T18:27:36+00:00 yes https://xdme.com/watch-book17-q055.html https://xdme.com/book17-thumbs/page-055.jpg What Is the Smallest Frog in the World? The smallest frog in the world is only about as long as a small pea! It lives in the rainforest of Papua New Guinea. Its science name is Paedophryne amauensis, and it was found jus https://socialmedia.xdme.com/tony/videos-book17/page-055.mp4 https://www.youtube.com/embed/wkHdpcyJVe0 116 2026-10-04T18:30:17+00:00 yes https://xdme.com/watch-book17-q056.html https://xdme.com/book17-thumbs/page-056.jpg Why Are So Many Rainforest Birds Brightly Colored? Rainforest birds wear bright colors to send messages! Colors help birds find friends, show they are healthy, and tell their own kind from look-alikes. In a dim, busy forest, bright https://socialmedia.xdme.com/tony/videos-book17/page-056.mp4 https://www.youtube.com/embed/6j1q0wNhauE 116 2026-10-04T18:32:50+00:00 yes https://xdme.com/watch-book17-q057.html https://xdme.com/book17-thumbs/page-057.jpg How Do Fruit Bats Find Ripe Fruit in the Dark? Fruit bats find ripe fruit in the dark using a super sense of smell and big, night-ready eyes! They can sniff a ripe fruit from far away. Then they swoop in, grab it, and fly off t https://socialmedia.xdme.com/tony/videos-book17/page-057.mp4 https://www.youtube.com/embed/Qh3GbaZ1-r4 111 2026-10-04T18:35:23+00:00 yes https://xdme.com/watch-book17-q058.html https://xdme.com/book17-thumbs/page-058.jpg Why Do Howler Monkeys Howl So Loudly? Howler monkeys howl so loudly because their bodies have a built-in loudspeaker! A special enlarged throat bone works like an echo chamber. It makes their calls super loud, so they https://socialmedia.xdme.com/tony/videos-book17/page-058.mp4 https://www.youtube.com/embed/-9qEl4ZyEZE 117 2026-10-04T18:38:26+00:00 yes https://xdme.com/watch-book17-q059.html https://xdme.com/book17-thumbs/page-059.jpg How Do Weaver Ants Build Nests From Living Leaves? Weaver ants build their nests by pulling living leaves together and stitching them with silk! Hundreds of workers team up for the job. The leaves stay on the tree, so the nest stay https://socialmedia.xdme.com/tony/videos-book17/page-059.mp4 https://www.youtube.com/embed/lJbJ_51RCDk 116 2026-10-04T18:41:29+00:00 yes https://xdme.com/watch-book17-q060.html https://xdme.com/book17-thumbs/page-060.jpg How Do Sleeping Animals Stay Safe in the Treetops? Sleeping animals stay safe in the treetops by choosing places that hunters cannot easily reach! Some sleep in nests, some in tree holes, and some on thick branches. Many even have https://socialmedia.xdme.com/tony/videos-book17/page-060.mp4 https://www.youtube.com/embed/U2yQ7gnkMS8 119 2026-10-04T18:44:34+00:00 yes https://xdme.com/watch-book17-q061.html https://xdme.com/book17-thumbs/page-061.jpg How Can a Snake Climb a Smooth Tree Trunk? Tree snakes climb smooth trunks using light bodies, grippy belly scales, and clever curves! Even tiny bumps in the bark give them something to push against. Climbing keeps them up https://socialmedia.xdme.com/tony/videos-book17/page-061.mp4 https://www.youtube.com/embed/dI07yGIhvdc 114 2026-10-04T18:47:05+00:00 yes https://xdme.com/watch-book17-q062.html https://xdme.com/book17-thumbs/page-062.jpg Why Do Orangutans Build a New Bed in the Trees Each Night? Orangutans build a fresh bed in the trees every night! They live in the rainforests of Borneo and Sumatra. A new bed each evening keeps out bugs and keeps them safe high above the https://socialmedia.xdme.com/tony/videos-book17/page-062.mp4 https://www.youtube.com/embed/0C7YgSGZYZw 114 2026-10-04T18:49:40+00:00 yes https://xdme.com/watch-book17-q063.html https://xdme.com/book17-thumbs/page-063.jpg How Do Chimpanzees Use Sticks as Tools? Chimpanzees are tool users who turn sticks into fishing rods and nutcrackers! They strip leaves from a twig to make a tool for fishing termites out of their mound. Young chimps lea https://socialmedia.xdme.com/tony/videos-book17/page-063.mp4 https://www.youtube.com/embed/F61xH18Ui0Q 113 2026-10-04T18:52:43+00:00 yes https://xdme.com/watch-book17-q064.html https://xdme.com/book17-thumbs/page-064.jpg How Can a Frog Become See-Through? Glass frogs have almost see-through bellies, and they can become even clearer when they rest! You can see their hearts and organs through their skin. A clear frog on a green leaf i https://socialmedia.xdme.com/tony/videos-book17/page-064.mp4 https://www.youtube.com/embed/mSRdp8PwRHw 112 2026-10-04T18:55:54+00:00 yes https://xdme.com/watch-book17-q065.html https://xdme.com/book17-thumbs/page-065.jpg Why Do Butterflies Gather at Muddy Puddles? Butterflies gather at muddy puddles to get minerals they cannot find in nectar! Scientists call this behavior puddling. Mud and damp sand hold salts and minerals that butterflies n https://socialmedia.xdme.com/tony/videos-book17/page-065.mp4 https://www.youtube.com/embed/Qyne9rLm934 121 2026-10-04T18:58:27+00:00 yes https://xdme.com/watch-book17-q066.html https://xdme.com/book17-thumbs/page-066.jpg Why Do Animals Use Vines as Highways? Animals use woody vines called lianas as highways high above the ground! Lianas wrap from tree to tree, making bridges across gaps in the canopy. Crossing a vine is faster and safe https://socialmedia.xdme.com/tony/videos-book17/page-066.mp4 https://www.youtube.com/embed/i903n1ihxGA 116 2026-10-04T19:01:30+00:00 yes https://xdme.com/watch-book17-q067.html https://xdme.com/book17-thumbs/page-067.jpg How Do Rainforest Animals Avoid Shouting Over One Another? Rainforest animals share the soundscape like singers in a choir! Each species tends to call at its own pitch or its own time. That way every voice stands out and nobody has to shou https://socialmedia.xdme.com/tony/videos-book17/page-067.mp4 https://www.youtube.com/embed/R-JxjoWvRpo 113 2026-10-04T19:04:02+00:00 yes https://xdme.com/watch-book17-q068.html https://xdme.com/book17-thumbs/page-068.jpg Why Do Some Rainforest Animals Eat Clay? Some rainforest animals eat clay because it gives them things their food lacks! Parrots and macaws gather at steep riverbanks called clay licks. Monkeys and other animals visit min https://socialmedia.xdme.com/tony/videos-book17/page-068.mp4 https://www.youtube.com/embed/HqqesH_J9P4 115 2026-10-04T19:06:43+00:00 yes https://xdme.com/watch-book17-q069.html https://xdme.com/book17-thumbs/page-069.jpg How Do Animals High in the Canopy Get Water to Drink? Animals high in the canopy drink from tiny pools and puddles in the treetops! Plants called bromeliads catch rain in their leaves like little cups. Droplets on leaves and juicy fru https://socialmedia.xdme.com/tony/videos-book17/page-069.mp4 https://www.youtube.com/embed/CgitFoDs4Cg 115 2026-10-04T19:09:45+00:00 yes https://xdme.com/watch-book17-q070.html https://xdme.com/book17-thumbs/page-070.jpg Who Shows Up When a Fig Tree Is Full of Fruit? A fig tree full of fruit is like a giant buffet, and the whole forest comes to eat! Monkeys, parrots, toucans, bats, and many other animals visit at all hours. Figs ripen in large https://socialmedia.xdme.com/tony/videos-book17/page-070.mp4 https://www.youtube.com/embed/jFnF05Of2Lw 114 2026-10-04T19:12:33+00:00 yes https://xdme.com/watch-book17-q071.html https://xdme.com/book17-thumbs/page-071.jpg How Can One Rainforest Tree Hold Thousands of Insects? One rainforest tree can be a whole city for insects! Scientists counted thousands of insects living in the branches of a single treetop. A tree has many different places to live, a https://socialmedia.xdme.com/tony/videos-book17/page-071.mp4 https://www.youtube.com/embed/8aDCuvTrix4 117 2026-10-04T19:15:37+00:00 yes https://xdme.com/watch-book17-q072.html https://xdme.com/book17-thumbs/page-072.jpg Why Do Monkeys Spend So Much Time Grooming Each Other? Monkeys groom each other to clean fur and to build friendships! Grooming removes dirt and tiny pests from fur. It also keeps the whole troop calm and working together. https://socialmedia.xdme.com/tony/videos-book17/page-072.mp4 https://www.youtube.com/embed/bLHIH9UIs_g 115 2026-10-04T19:18:11+00:00 yes https://xdme.com/watch-book17-q073.html https://xdme.com/book17-thumbs/page-073.jpg How Do Canopy Animals Know Which Tree Is Fruiting? Canopy animals find fruiting trees using their eyes, their noses, and their memories! A ripe tree sends out clear signals. Smart animals remember where the best trees are and follo https://socialmedia.xdme.com/tony/videos-book17/page-073.mp4 https://www.youtube.com/embed/S5LrV0hJZiU 114 2026-10-04T19:21:13+00:00 yes https://xdme.com/watch-book17-q074.html https://xdme.com/book17-thumbs/page-074.jpg Why Do Morpho Butterflies Flash Bright Blue? A morpho butterfly's wings flash bright blue because of tiny structures, not blue paint! The wing scales bounce blue light back to your eyes. That is called structural color, and i https://socialmedia.xdme.com/tony/videos-book17/page-074.mp4 https://www.youtube.com/embed/TWi4pejELp4 117 2026-10-04T19:24:46+00:00 yes https://xdme.com/watch-book17-q075.html https://xdme.com/book17-thumbs/page-075.jpg Why Do So Many Animals Live in the Canopy Instead of on the Ground? So many animals live in the canopy because that is where the food and sunlight are! The treetops are full of leaves, flowers, and fruit. Many rainforest animals spend their whole l https://socialmedia.xdme.com/tony/videos-book17/page-075.mp4 https://www.youtube.com/embed/8oRKvQKyhnc 115 2026-10-04T19:29:19+00:00 yes https://xdme.com/watch-book17-q076.html https://xdme.com/book17-thumbs/page-076.jpg Why Do Rainforest Leaves Have Long, Pointed “Drip Tips”? Many rainforest leaves end in a long, pointed tip called a drip tip! It works like a spout, letting rainwater run off the leaf quickly. It is the plant's built-in rain gutter. https://socialmedia.xdme.com/tony/videos-book17/page-076.mp4 https://www.youtube.com/embed/qqYe_gplZxI 111 2026-10-04T16:11:04+00:00 yes https://xdme.com/watch-book17-q077.html https://xdme.com/book17-thumbs/page-077.jpg Why Do Some Rainforest Trees Have Giant Flared Roots Like Walls? Buttress roots are giant, wall-like ridges that help tall trees stand up! Rainforest soil is thin, so tall trees need extra support. These roots spread out from the trunk like the https://socialmedia.xdme.com/tony/videos-book17/page-077.mp4 https://www.youtube.com/embed/l9GYaJamHZg 116 2026-10-04T16:11:05+00:00 yes https://xdme.com/watch-book17-q078.html https://xdme.com/book17-thumbs/page-078.jpg What Is an Epiphyte, and Why Do Some Plants Grow on Other Plants? An epiphyte is a plant that grows on another plant without harming it! Ferns, mosses, orchids, and bromeliads often live this way. Up on a branch, they find sunlight that the dark https://socialmedia.xdme.com/tony/videos-book17/page-078.mp4 https://www.youtube.com/embed/kyl5FfAGxZw 111 2026-10-04T16:11:06+00:00 yes https://xdme.com/watch-book17-q079.html https://xdme.com/book17-thumbs/page-079.jpg How Do Bromeliads Hold Tiny Ponds in the Treetops? A bromeliad is a plant with leaves that form a cup, and the cup holds a tiny pond! Rainwater collects in the center, high up in the treetops. Whole communities of animals live in t https://socialmedia.xdme.com/tony/videos-book17/page-079.mp4 https://www.youtube.com/embed/gjM37r7-5lw 111 2026-10-04T16:11:21+00:00 yes https://xdme.com/watch-book17-q080.html https://xdme.com/book17-thumbs/page-080.jpg How Does a Strangler Fig Grow Around Another Tree? A strangler fig starts life high in a tree and slowly wraps around it! Its roots grow down the trunk to the soil. Over many years, they form a lattice around the host tree. https://socialmedia.xdme.com/tony/videos-book17/page-080.mp4 https://www.youtube.com/embed/ORjCH11g5UE 113 2026-10-04T16:11:22+00:00 yes https://xdme.com/watch-book17-q081.html https://xdme.com/book17-thumbs/page-081.jpg Why Are Orchid Seeds as Tiny as Dust? Orchid seeds are as tiny as dust so the wind can carry them far away! One seed pod can hold millions of seeds. Making so many tiny seeds gives a few of them a chance to land in jus https://socialmedia.xdme.com/tony/videos-book17/page-081.mp4 https://www.youtube.com/embed/bj2k4uDZM6I 110 2026-10-04T16:12:25+00:00 yes https://xdme.com/watch-book17-q082.html https://xdme.com/book17-thumbs/page-082.jpg Why Do Some Plants on the Forest Floor Have Leaves as Big as Umbrellas? Some plants on the forest floor have leaves as big as umbrellas because the floor is dim! Only a little sunlight filters down through the canopy. A big leaf can catch more of that https://socialmedia.xdme.com/tony/videos-book17/page-082.mp4 https://www.youtube.com/embed/PpzjoPaGf7Y 109 2026-10-04T16:14:57+00:00 yes https://xdme.com/watch-book17-q083.html https://xdme.com/book17-thumbs/page-083.jpg What Is the Titan Arum, and Why Does It Smell Terrible? The titan arum is a giant rainforest plant that smells terrible on purpose! It makes one of the largest flower clusters in the world. The stink attracts the insects that help it ma https://socialmedia.xdme.com/tony/videos-book17/page-083.mp4 https://www.youtube.com/embed/yulSRlJpKz4 111 2026-10-04T16:17:30+00:00 yes https://xdme.com/watch-book17-q084.html https://xdme.com/book17-thumbs/page-084.jpg How Do Pitcher Plants Trap Insects? Pitcher plants trap insects in cup-shaped leaves with a slippery rim! Inside the cup is a pool of liquid that digests the insects. It is how the plant gets food in poor soil. https://socialmedia.xdme.com/tony/videos-book17/page-084.mp4 https://www.youtube.com/embed/IjGBktTKbzw 111 2026-10-04T16:21:04+00:00 yes https://xdme.com/watch-book17-q085.html https://xdme.com/book17-thumbs/page-085.jpg Why Are Leaves at the Top of the Canopy Smaller and Tougher than Those Below? Leaves at the top of the canopy are small and tough, while leaves below are big and thin! The top gets hot, windy, and very sunny. The shady lower layers need to catch every bit of https://socialmedia.xdme.com/tony/videos-book17/page-085.mp4 https://www.youtube.com/embed/xVGvzshGPEQ 105 2026-10-04T16:23:36+00:00 yes https://xdme.com/watch-book17-q086.html https://xdme.com/book17-thumbs/page-086.jpg Why Do the Leaves of a Sensitive Plant Fold Up When Touched? The sensitive plant folds up its leaves in seconds when it is touched! It is called the mimosa, and it comes from the tropical Americas. The leaves slowly open again after a few mi https://socialmedia.xdme.com/tony/videos-book17/page-086.mp4 https://www.youtube.com/embed/33QySrQ6V1Q 116 2026-10-04T16:26:40+00:00 yes https://xdme.com/watch-book17-q087.html https://xdme.com/book17-thumbs/page-087.jpg How Can a Vine Grow Hundreds of Feet Without a Thick Trunk? Lianas are woody vines that reach the sunny canopy without growing a thick trunk! They start as seedlings on the ground. Then they climb a tree to get where the light is. https://socialmedia.xdme.com/tony/videos-book17/page-087.mp4 https://www.youtube.com/embed/EQ_k5YT0fNg 113 2026-10-04T16:29:12+00:00 yes https://xdme.com/watch-book17-q088.html https://xdme.com/book17-thumbs/page-088.jpg How Does a Cacao Pod Turn Into Chocolate? Chocolate starts as seeds inside a pod that grows on a cacao tree! The tree grows in the shade of the rainforest. It takes many steps to turn those seeds into a chocolate bar. https://socialmedia.xdme.com/tony/videos-book17/page-088.mp4 https://www.youtube.com/embed/wdh8hJUTCW8 116 2026-10-04T16:32:16+00:00 yes https://xdme.com/watch-book17-q089.html https://xdme.com/book17-thumbs/page-089.jpg Why Do Some Tropical Fruit Trees Grow Flowers and Fruit Right on Their Trunks? Some tropical trees grow flowers and fruit right on their trunks! Cacao and jackfruit trees are famous for it. Scientists call this strange habit cauliflory. https://socialmedia.xdme.com/tony/videos-book17/page-089.mp4 https://www.youtube.com/embed/-rWnPG0sEVw 115 2026-10-04T16:34:50+00:00 yes https://xdme.com/watch-book17-q090.html https://xdme.com/book17-thumbs/page-090.jpg Why Do Rainforest Fruits Come in So Many Colors? Rainforest fruits come in many colors to advertise to the animals that spread their seeds! Color and smell are like signs saying, ripe and ready, come and get me. When a fruit is r https://socialmedia.xdme.com/tony/videos-book17/page-090.mp4 https://www.youtube.com/embed/9-cPx2oe72g 113 2026-10-04T16:37:52+00:00 yes https://xdme.com/watch-book17-q091.html https://xdme.com/book17-thumbs/page-091.jpg Why Do Some Rainforest Seeds Spin Like Helicopters? Some rainforest seeds have a wing that makes them spin like tiny helicopters! Tall trees, such as dipterocarps in Southeast Asia, use this trick. The spin slows the fall so the bre https://socialmedia.xdme.com/tony/videos-book17/page-091.mp4 https://www.youtube.com/embed/AZFuULuRCOI 111 2026-10-04T16:40:26+00:00 yes https://xdme.com/watch-book17-q092.html https://xdme.com/book17-thumbs/page-092.jpg Why Can’t Brazil Nut Trees Grow Well Without a Rodent and a Bee? Brazil nut trees need two helpers, a big bee and a rodent called the agouti! The bee pollinates the flowers, and the agouti plants the seeds. Without both, there would be no Brazil https://socialmedia.xdme.com/tony/videos-book17/page-092.mp4 https://www.youtube.com/embed/MeARQWQv8ZY 114 2026-10-04T16:43:33+00:00 yes https://xdme.com/watch-book17-q093.html https://xdme.com/book17-thumbs/page-093.jpg How Do Some Rainforest Plants Call for Bodyguards? Some rainforest plants call for bodyguards when they are being eaten! They release a special scent into the air. Helpful insects smell it and come to the rescue. https://socialmedia.xdme.com/tony/videos-book17/page-093.mp4 https://www.youtube.com/embed/3F8-WgR-VpM 116 2026-10-04T16:46:06+00:00 yes https://xdme.com/watch-book17-q094.html https://xdme.com/book17-thumbs/page-094.jpg Why Do Some Tree Trunks Bristle with Spikes? Some tree trunks bristle with spikes to protect them while they are young! Certain palms and kapok trees grow sharp thorns on their trunks. The spikes make it hard for climbing ani https://socialmedia.xdme.com/tony/videos-book17/page-094.mp4 https://www.youtube.com/embed/B3ZKCd2LqTU 113 2026-10-04T16:48:45+00:00 yes https://xdme.com/watch-book17-q095.html https://xdme.com/book17-thumbs/page-095.jpg What Is the World’s Biggest Flower, and Why Does It Have No Leaves? The world's biggest single flower is the rafflesia, and it has no leaves at all! It grows in the rainforests of Southeast Asia, in places such as Indonesia. It lives inside a vine, https://socialmedia.xdme.com/tony/videos-book17/page-095.mp4 https://www.youtube.com/embed/Cnv3XFro4Fk 114 2026-10-04T16:51:32+00:00 yes https://xdme.com/watch-book17-q096.html https://xdme.com/book17-thumbs/page-096.jpg Which Plant Has the Longest Leaves in the World? The raffia palm has the longest leaves of any plant in the world! Its leaves can be over 80 feet long, or about 25 meters. That is longer than a school bus. https://socialmedia.xdme.com/tony/videos-book17/page-096.mp4 https://www.youtube.com/embed/6UAFkf3skYM 116 2026-10-04T16:54:05+00:00 yes https://xdme.com/watch-book17-q097.html https://xdme.com/book17-thumbs/page-097.jpg Why Are Young Leaves on Many Rainforest Trees Red or Pink? Many rainforest trees send out new leaves that are red, pink, purple, or even white! The color is only temporary, like a costume. The leaves turn green once they are tough and stro https://socialmedia.xdme.com/tony/videos-book17/page-097.mp4 https://www.youtube.com/embed/Cw71KmH1oN4 112 2026-10-04T16:57:08+00:00 yes https://xdme.com/watch-book17-q098.html https://xdme.com/book17-thumbs/page-098.jpg How Can a Giant Water Lily Leaf Be So Big and So Strong? The giant Amazon water lily has floating leaves up to 10 feet wide, and they are surprisingly strong! The secret is a hidden web of ribs underneath. The ribs spread out the weight, https://socialmedia.xdme.com/tony/videos-book17/page-098.mp4 https://www.youtube.com/embed/ucsBhYuBSxI 114 2026-10-04T16:59:42+00:00 yes https://xdme.com/watch-book17-q099.html https://xdme.com/book17-thumbs/page-099.jpg How Do Rainforest Plants Race Each Other for Sunlight? Rainforest plants race each other for sunlight, and the race never ends! Down on the floor, it is very dark. Every plant has a strategy to reach the light, and each strategy is dif https://socialmedia.xdme.com/tony/videos-book17/page-099.mp4 https://www.youtube.com/embed/sM5F33j6G8E 113 2026-10-04T17:02:45+00:00 yes https://xdme.com/watch-book17-q100.html https://xdme.com/book17-thumbs/page-100.jpg Do Scientists Still Find New Rainforest Plants? Yes, scientists still find new rainforest plants every single year! Around the world, about two thousand new plant species are named each year. Many of them come from tropical fore https://socialmedia.xdme.com/tony/videos-book17/page-100.mp4 https://www.youtube.com/embed/6NDKB2q0XJA 115 2026-10-04T17:05:19+00:00 yes https://xdme.com/watch-book17-q101.html https://xdme.com/book17-thumbs/page-101.jpg Why Do Leafcutter Ants Carry Pieces of Leaves They Never Eat? Leafcutter ants carry leaf pieces home, but they never eat them! The leaves are food for a garden. The ants chew them into a soft green mulch, and a tiny fungus grows on it. https://socialmedia.xdme.com/tony/videos-book17/page-101.mp4 https://www.youtube.com/embed/xqlWxqeKROw 121 2026-10-04T17:08:32+00:00 yes https://xdme.com/watch-book17-q102.html https://xdme.com/book17-thumbs/page-102.jpg How Do Army Ants Build Bridges with Their Own Bodies? Army ants link their own bodies together to make living bridges! When a gap is in the way, workers hold on to each other with their legs and tiny hooks. Then the rest of the colony https://socialmedia.xdme.com/tony/videos-book17/page-102.mp4 https://www.youtube.com/embed/gHeGKbUucww 114 2026-10-04T17:11:19+00:00 yes https://xdme.com/watch-book17-q103.html https://xdme.com/book17-thumbs/page-103.jpg Why Do Some Ants Live Inside Special Trees? Some ants live inside special trees because the tree gives them a home and food! In return, the ants protect the tree from hungry insects and smothering vines. Scientists call a te https://socialmedia.xdme.com/tony/videos-book17/page-103.mp4 https://www.youtube.com/embed/mrZe1LSrdaw 112 2026-10-04T17:13:51+00:00 yes https://xdme.com/watch-book17-q104.html https://xdme.com/book17-thumbs/page-104.jpg How Do Fig Wasps and Fig Trees Depend on Each Other? Fig trees and fig wasps need each other to make the next generation! The tiny wasp carries pollen to the tree, and the tree gives the wasp a place for its babies. Neither one could https://socialmedia.xdme.com/tony/videos-book17/page-104.mp4 https://www.youtube.com/embed/S8UH4KRaiN0 116 2026-10-04T17:16:26+00:00 yes https://xdme.com/watch-book17-q105.html https://xdme.com/book17-thumbs/page-105.jpg What Does It Mean When Two Living Things Are Partners? When two living things are partners, they help each other so both do better! Scientists call this mutualism, and it means both win. The rainforest is full of these teams. https://socialmedia.xdme.com/tony/videos-book17/page-105.mp4 https://www.youtube.com/embed/u783r4ThzWw 111 2026-10-04T17:18:58+00:00 yes https://xdme.com/watch-book17-q106.html https://xdme.com/book17-thumbs/page-106.jpg How Do Hummingbirds and Heliconia Flowers Fit Together Like a Lock and Key? Some rainforest hummingbirds and flowers fit together like a lock and key! The bird's beak and the flower's tube have the same curve. That perfect fit helps the right bird carry th https://socialmedia.xdme.com/tony/videos-book17/page-106.mp4 https://www.youtube.com/embed/K9a1j2FBX0w 113 2026-10-04T17:22:30+00:00 yes https://xdme.com/watch-book17-q107.html https://xdme.com/book17-thumbs/page-107.jpg Why Do Birds Visit Red Flowers but Bees Prefer Blue and Yellow? Flowers use color to invite the right visitors! Birds can see red very well, but bees see colors differently, so red looks dull to them. That is why birds love red flowers and bees https://socialmedia.xdme.com/tony/videos-book17/page-107.mp4 https://www.youtube.com/embed/uGUuUsvXOUo 113 2026-10-04T17:25:04+00:00 yes https://xdme.com/watch-book17-q108.html https://xdme.com/book17-thumbs/page-108.jpg How Do Some Birds Follow Army Ants to Find Food? Some birds follow army ants because the ants chase food out of hiding! The birds do not eat the ants. They wait for the insects, spiders, and lizards that scramble away. https://socialmedia.xdme.com/tony/videos-book17/page-108.mp4 https://www.youtube.com/embed/To3h6Qpnlqk 112 2026-10-04T17:28:07+00:00 yes https://xdme.com/watch-book17-q109.html https://xdme.com/book17-thumbs/page-109.jpg How Does a Bucket Orchid Make Bees Take a Bath? A bucket orchid has a flower shaped like a bucket, filled with liquid! Male orchid bees come to collect its perfume, and some slip in for a splash. Then the orchid sends them out t https://socialmedia.xdme.com/tony/videos-book17/page-109.mp4 https://www.youtube.com/embed/-1w3lms65qM 113 2026-10-04T17:30:42+00:00 yes https://xdme.com/watch-book17-q110.html https://xdme.com/book17-thumbs/page-110.jpg How Do Dung Beetles Help the Forest Floor? Dung beetles are the clean-up crew of the forest floor! They roll or bury animal droppings, which puts nutrients back into the soil. That helps new plants grow. https://socialmedia.xdme.com/tony/videos-book17/page-110.mp4 https://www.youtube.com/embed/4ytMdGiIIyk 109 2026-10-04T17:33:14+00:00 yes https://xdme.com/watch-book17-q111.html https://xdme.com/book17-thumbs/page-111.jpg How Do Poison Dart Frog Parents Carry Tadpoles to Tiny Pools? Poison dart frog parents carry their tadpoles to tiny pools high in the trees! The tadpoles wriggle onto a parent's back and ride up the trunk. It is a lot of care for a very small https://socialmedia.xdme.com/tony/videos-book17/page-111.mp4 https://www.youtube.com/embed/hkwuchJQrPc 115 2026-10-04T17:36:17+00:00 yes https://xdme.com/watch-book17-q112.html https://xdme.com/book17-thumbs/page-112.jpg How Can a Frog Smaller than Your Thumb Be So Loud? A tiny frog can be loud because it uses its whole body like a speaker! The coquí frog of Puerto Rico is about the size of a quarter. Its call can be as loud as a lawn mower if you https://socialmedia.xdme.com/tony/videos-book17/page-112.mp4 https://www.youtube.com/embed/0tWRVfeZcHc 104 2026-10-04T17:38:50+00:00 yes https://xdme.com/watch-book17-q113.html https://xdme.com/book17-thumbs/page-113.jpg Why Do Some Rainforest Spiders Live Together in Giant Webs? Most spiders live alone, but a few kinds in the Amazon live in big family groups! Hundreds or thousands share one giant web. Working together helps them survive in the rainforest. https://socialmedia.xdme.com/tony/videos-book17/page-113.mp4 https://www.youtube.com/embed/RLw_5asqmrY 114 2026-10-04T17:41:22+00:00 yes https://xdme.com/watch-book17-q114.html https://xdme.com/book17-thumbs/page-114.jpg Why Are There More Kinds of Beetles than Anything Else? There are more kinds of beetles than any other animal group! About one out of every four known animal species is a beetle. They live almost everywhere on land, from rainforests to https://socialmedia.xdme.com/tony/videos-book17/page-114.mp4 https://www.youtube.com/embed/4TJ4N6RgG8I 113 2026-10-04T17:44:26+00:00 yes https://xdme.com/watch-book17-q115.html https://xdme.com/book17-thumbs/page-115.jpg Why Do Some Rainforest Bees Have No Sting? Some rainforest bees have no sting at all! Their stingers are so small that they do not work. They live in forests in warm places around the world. https://socialmedia.xdme.com/tony/videos-book17/page-115.mp4 https://www.youtube.com/embed/tgzKzW3GVLo 113 2026-10-04T17:47:02+00:00 yes https://xdme.com/watch-book17-q116.html https://xdme.com/book17-thumbs/page-116.jpg Why Does the Atlas Moth Have No Mouth as an Adult? The atlas moth has no working mouth as an adult because it does all its eating as a caterpillar! It stores up fat, and that fat powers its short adult life. Adult life is just long https://socialmedia.xdme.com/tony/videos-book17/page-116.mp4 https://www.youtube.com/embed/wLam7R6cdn0 111 2026-10-04T17:50:12+00:00 yes https://xdme.com/watch-book17-q117.html https://xdme.com/book17-thumbs/page-117.jpg What Lives in a Handful of Rainforest Soil? A handful of rainforest soil is like a tiny hidden city! It is packed with living things, most too small to see without a microscope. Together they keep the forest healthy. https://socialmedia.xdme.com/tony/videos-book17/page-117.mp4 https://www.youtube.com/embed/YU58zPxGc4g 117 2026-10-04T17:52:47+00:00 yes https://xdme.com/watch-book17-q118.html https://xdme.com/book17-thumbs/page-118.jpg How Strong Is a Rhinoceros Beetle? Rhinoceros beetles are super strong for their size! Some, like the Hercules beetle, can lift many times their own weight. Being tiny is part of the secret. https://socialmedia.xdme.com/tony/videos-book17/page-118.mp4 https://www.youtube.com/embed/qLn_qAclY5c 108 2026-10-04T17:55:20+00:00 yes https://xdme.com/watch-book17-q119.html https://xdme.com/book17-thumbs/page-119.jpg How Do Big Fruit-Eating Birds Plant New Trees? Big fruit-eating birds are gardeners of the forest! They swallow whole fruit, carry the seeds far away, and drop them in new places. That is how new trees get started. https://socialmedia.xdme.com/tony/videos-book17/page-119.mp4 https://www.youtube.com/embed/YwhMD4MSZtA 116 2026-10-04T17:58:23+00:00 yes https://xdme.com/watch-book17-q120.html https://xdme.com/book17-thumbs/page-120.jpg How Do Glasswing Butterflies Get See-Through Wings? Glasswing butterflies have see-through wings because of tiny structures, not color! Their clear wings have almost no colored scales. Instead, microscopic pillars stop light from bo https://socialmedia.xdme.com/tony/videos-book17/page-120.mp4 https://www.youtube.com/embed/7FtbiXIZ2b4 121 2026-10-04T18:01:26+00:00 yes https://xdme.com/watch-book17-q121.html https://xdme.com/book17-thumbs/page-121.jpg Why Does the Durian Fruit Smell So Strong? The durian fruit smells so strong because its smell is a signal to animals! In the forests of Southeast Asia, the smell calls hungry animals from far away. Those animals help sprea https://socialmedia.xdme.com/tony/videos-book17/page-121.mp4 https://www.youtube.com/embed/JcBZ4caDC20 117 2026-10-04T18:03:59+00:00 yes https://xdme.com/watch-book17-q122.html https://xdme.com/book17-thumbs/page-122.jpg Who Works the Night Shift in the Rainforest? When the Sun sets, a whole different crew wakes up in the rainforest! Night animals come out to eat, hunt, and sing. The night shift is as busy as the day shift. https://socialmedia.xdme.com/tony/videos-book17/page-122.mp4 https://www.youtube.com/embed/XiD9N2c53qs 113 2026-10-04T18:07:02+00:00 yes https://xdme.com/watch-book17-q123.html https://xdme.com/book17-thumbs/page-123.jpg What Tiny Flies Pollinate Chocolate Trees? Chocolate trees are pollinated by tiny flies called midges, not by bees! Without these little insects, there would be far fewer cocoa beans. So chocolate depends on the insects of https://socialmedia.xdme.com/tony/videos-book17/page-123.mp4 https://www.youtube.com/embed/JQjN_QUk4AI 119 2026-10-04T18:09:49+00:00 yes https://xdme.com/watch-book17-q124.html https://xdme.com/book17-thumbs/page-124.jpg What Is a Keystone Species in a Rainforest? A keystone species is one that many other living things depend on! It matters much more than you would expect from how many there are. If it disappears, the whole community can cha https://socialmedia.xdme.com/tony/videos-book17/page-124.mp4 https://www.youtube.com/embed/MFpmRaG5rK8 118 2026-10-04T18:12:51+00:00 yes https://xdme.com/watch-book17-q125.html https://xdme.com/book17-thumbs/page-125.jpg What Can Happen to a Rainforest If One Kind of Animal Disappears? In a rainforest, animals and plants are linked like threads in a web! When one kind of animal disappears, other living things can be affected too. Every thread matters. https://socialmedia.xdme.com/tony/videos-book17/page-125.mp4 https://www.youtube.com/embed/I5cgv68yA2Y 118 2026-10-04T18:15:24+00:00 yes https://xdme.com/watch-book17-q126.html https://xdme.com/book17-thumbs/page-126.jpg How Do Scientists Reach the Top of a Rainforest? Scientists reach the top of a rainforest with special gear, training, and a lot of care! The treetops are called the canopy, and they are full of life. For a long time, the canopy https://socialmedia.xdme.com/tony/videos-book17/page-126.mp4 https://www.youtube.com/embed/Ok5FFMPDlvM 121 2026-10-04T18:18:27+00:00 yes https://xdme.com/watch-book17-q127.html https://xdme.com/book17-thumbs/page-127.jpg What Is a Canopy Walkway, and Why Do People Build Them? A canopy walkway is a bridge of ropes and boards strung between tall trees! It lets people walk safely through the treetops. Walkways help us study the rainforest without hurting t https://socialmedia.xdme.com/tony/videos-book17/page-127.mp4 https://www.youtube.com/embed/EcCTpBCSR6w 115 2026-10-04T18:21:30+00:00 yes https://xdme.com/watch-book17-q128.html https://xdme.com/book17-thumbs/page-128.jpg How Do Scientists Use Sound Recorders to Listen to a Rainforest? Scientists listen to the rainforest by hanging sound recorders in the trees! The recorders listen for days or weeks, even when no one is there. Later, people and computers sort out https://socialmedia.xdme.com/tony/videos-book17/page-128.mp4 https://www.youtube.com/embed/r4909dXwCDo 120 2026-10-04T18:24:32+00:00 yes https://xdme.com/watch-book17-q129.html https://xdme.com/book17-thumbs/page-129.jpg How Do Drones and Lasers Help Scientists Map a Rainforest? Drones and lasers help scientists map a rainforest without climbing every tree! Drones take photos from above, and lasers measure the height of the forest. A computer puts it toget https://socialmedia.xdme.com/tony/videos-book17/page-129.mp4 https://www.youtube.com/embed/sXkf5oilUQo 114 2026-10-04T18:27:04+00:00 yes https://xdme.com/watch-book17-q130.html https://xdme.com/book17-thumbs/page-130.jpg How Can Two Look-Alike Rainforest Animals Turn Out to Be Different Species? Two animals can look almost the same and still be different species! Scientists look at calls, DNA, and who the animals mate with. Look-alike species are called cryptic species. https://socialmedia.xdme.com/tony/videos-book17/page-130.mp4 https://www.youtube.com/embed/9rNzQemxxHY 120 2026-10-04T18:30:19+00:00 yes https://xdme.com/watch-book17-q131.html https://xdme.com/book17-thumbs/page-131.jpg Why Do Scientists Put Numbered Tags on Rainforest Trees? Scientists put numbered tags on rainforest trees so they can follow each tree for years! Every tag is like a name or a number for that tree. Over time, the records tell the story o https://socialmedia.xdme.com/tony/videos-book17/page-131.mp4 https://www.youtube.com/embed/ybOT6MOBDWE 113 2026-10-04T18:32:51+00:00 yes https://xdme.com/watch-book17-q132.html https://xdme.com/book17-thumbs/page-132.jpg What Medicines Come From Rainforest Plants? Many medicines first came from plants, and rainforests hold a lot of plants! Scientists study them carefully in laboratories. Never try a wild plant as medicine, because it can be https://socialmedia.xdme.com/tony/videos-book17/page-132.mp4 https://www.youtube.com/embed/roB0HoCGt1k 124 2026-10-04T18:35:55+00:00 yes https://xdme.com/watch-book17-q133.html https://xdme.com/book17-thumbs/page-133.jpg Which Foods That We Eat Began in Tropical Forests? Many foods we eat began in warm tropical regions, and a number of them in or near rainforests! People now grow them on farms all over the world, so they can reach stores far away. https://socialmedia.xdme.com/tony/videos-book17/page-133.mp4 https://www.youtube.com/embed/6TQObCQkG1Y 117 2026-10-04T18:38:28+00:00 yes https://xdme.com/watch-book17-q134.html https://xdme.com/book17-thumbs/page-134.jpg Which Tree Gives Us the Stretchy Material Called Natural Rubber? Natural rubber comes from the milky sap of the rubber tree! The sap is called latex, and it first grew in the Amazon rainforest. The stretchy material is used to make tires, gloves https://socialmedia.xdme.com/tony/videos-book17/page-134.mp4 https://www.youtube.com/embed/GkFtxFZqjfM 115 2026-10-04T18:41:31+00:00 yes https://xdme.com/watch-book17-q135.html https://xdme.com/book17-thumbs/page-135.jpg How Is Chewing Gum Linked to a Rainforest Tree? Long ago, chewing gum was made from the milky sap of a rainforest tree! The sap is called chicle, and it comes from the sapodilla tree. These trees grow in the forests of Central A https://socialmedia.xdme.com/tony/videos-book17/page-135.mp4 https://www.youtube.com/embed/0mqDh3f94Mw 114 2026-10-04T18:44:03+00:00 yes https://xdme.com/watch-book17-q136.html https://xdme.com/book17-thumbs/page-136.jpg Why Does Soil Wash Away When Rainforest Trees Are Cut? Soil washes away when trees are cut because trees protect the ground! Leaves slow down the rain, and roots hold the soil in place. Without them, heavy rain can carry the soil away. https://socialmedia.xdme.com/tony/videos-book17/page-136.mp4 https://www.youtube.com/embed/_hg6w1U1IRc 112 2026-10-04T18:47:07+00:00 yes https://xdme.com/watch-book17-q137.html https://xdme.com/book17-thumbs/page-137.jpg Why Are Some Rainforests Getting Smaller? Some rainforests are getting smaller because people have cleared parts of them! Forest land has been used for farms, cattle, roads, mines, and wood. When large areas are cleared, a https://socialmedia.xdme.com/tony/videos-book17/page-137.mp4 https://www.youtube.com/embed/wyrw3oXo36U 118 2026-10-04T18:50:11+00:00 yes https://xdme.com/watch-book17-q138.html https://xdme.com/book17-thumbs/page-138.jpg What Happens to Animals When a Forest Is Cut Into Small Pieces? When a forest is cut into small pieces, animals have a hard time finding what they need! Open ground can be a barrier, and small patches may lose species over time. Large, connecte https://socialmedia.xdme.com/tony/videos-book17/page-138.mp4 https://www.youtube.com/embed/SzbumllfFmA 120 2026-10-04T18:52:44+00:00 yes https://xdme.com/watch-book17-q139.html https://xdme.com/book17-thumbs/page-139.jpg What Is Ecotourism, and How Can Visits Help a Forest? Ecotourism means visiting nature in a way that protects it and helps local people! Visitors follow rules, stay on trails, and hire local guides. The money they spend can help pay t https://socialmedia.xdme.com/tony/videos-book17/page-139.mp4 https://www.youtube.com/embed/lzBh4EdmooE 123 2026-10-04T18:55:55+00:00 yes https://xdme.com/watch-book17-q140.html https://xdme.com/book17-thumbs/page-140.jpg What Is Shade-Grown Coffee and Why Does It Help Forests? Shade-grown coffee is grown under tall trees instead of in open, sunny fields! The trees give homes to birds, bats, and insects. That helps protect forests while farmers still make https://socialmedia.xdme.com/tony/videos-book17/page-140.mp4 https://www.youtube.com/embed/oiJKDaxowYE 113 2026-10-04T18:58:28+00:00 yes https://xdme.com/watch-book17-q141.html https://xdme.com/book17-thumbs/page-141.jpg How Does Planting Trees Help Heal a Rainforest? Planting trees helps heal a rainforest by bringing back homes for wildlife! Groups collect seeds from native trees, grow them in nurseries, and plant them where the forest was lost https://socialmedia.xdme.com/tony/videos-book17/page-141.mp4 https://www.youtube.com/embed/7S6DPWN5xvQ 117 2026-10-04T19:01:31+00:00 yes https://xdme.com/watch-book17-q142.html https://xdme.com/book17-thumbs/page-142.jpg What Can Kids Do to Help Rainforests? Kids can help rainforests in lots of simple ways! Small steps by lots of people make a big difference. The first step is learning and sharing what you know. https://socialmedia.xdme.com/tony/videos-book17/page-142.mp4 https://www.youtube.com/embed/8nBvcV8JP5E 115 2026-10-04T19:04:11+00:00 yes https://xdme.com/watch-book17-q143.html https://xdme.com/book17-thumbs/page-143.jpg What Jobs Do People Have Studying and Protecting Rainforests? Lots of different jobs help us study and protect rainforests! Some people work with plants, some with animals, and some with machines. Others work with words and pictures. https://socialmedia.xdme.com/tony/videos-book17/page-143.mp4 https://www.youtube.com/embed/4dOWGlnZjJI 121 2026-10-04T19:06:44+00:00 yes https://xdme.com/watch-book17-q144.html https://xdme.com/book17-thumbs/page-144.jpg How Do Rangers Help Protect Rainforest Animals and Plants? Rangers help protect rainforest animals and plants by watching over the forest every day! They walk or boat through protected areas and work with nearby communities. Their goal is https://socialmedia.xdme.com/tony/videos-book17/page-144.mp4 https://www.youtube.com/embed/t8Nx4eznM3o 113 2026-10-04T19:09:59+00:00 yes https://xdme.com/watch-book17-q145.html https://xdme.com/book17-thumbs/page-145.jpg What Is a Protected Area, and Why Do Rainforests Need Them? A protected area is land set aside so wildlife and plants can thrive! It might be a national park or a reserve, with rules about what people can do. Rainforests need them to stay h https://socialmedia.xdme.com/tony/videos-book17/page-145.mp4 https://www.youtube.com/embed/Fx3o7x1U5pU 119 2026-10-04T19:12:34+00:00 yes https://xdme.com/watch-book17-q146.html https://xdme.com/book17-thumbs/page-146.jpg How Do Wildlife Rescue Centers Help Animals Return to the Forest? Wildlife rescue centers care for animals that are hurt or have lost their parents! Their goal is to help each animal get ready to return to the forest. Wild animals belong in the w https://socialmedia.xdme.com/tony/videos-book17/page-146.mp4 https://www.youtube.com/embed/h_CVlHmJC4c 116 2026-10-04T19:15:39+00:00 yes https://xdme.com/watch-book17-q147.html https://xdme.com/book17-thumbs/page-147.jpg Why Do Rainforests Matter to People Who Live Far Away? Rainforests matter to people everywhere, even far away! They affect weather, store carbon, and shelter a huge share of Earth's wildlife. A healthy forest helps the whole planet. https://socialmedia.xdme.com/tony/videos-book17/page-147.mp4 https://www.youtube.com/embed/OiY1RGIvR_U 118 2026-10-04T19:18:12+00:00 yes https://xdme.com/watch-book17-q148.html https://xdme.com/book17-thumbs/page-148.jpg How Do Birds That Visit Your Backyard Depend on Rainforests? Many birds that visit your backyard spend part of the year in tropical forests! They nest in Canada and the United States in summer. Then they travel south to Central and South Ame https://socialmedia.xdme.com/tony/videos-book17/page-148.mp4 https://www.youtube.com/embed/Jp23hKS1Ej8 118 2026-10-04T19:21:15+00:00 yes https://xdme.com/watch-book17-q149.html https://xdme.com/book17-thumbs/page-149.jpg How Can a Jar of Plants Show How a Rainforest Recycles Water? A closed jar of plants shows how a rainforest recycles water! Water rises, collects, and drips back down again, like a tiny rainforest in a jar. The same water keeps going around a https://socialmedia.xdme.com/tony/videos-book17/page-149.mp4 https://www.youtube.com/embed/MSj_Z_kJufw 113 2026-10-04T19:24:48+00:00 yes https://xdme.com/watch-book17-q150.html https://xdme.com/book17-thumbs/page-150.jpg What Do Scientists Still Wonder About Rainforests? Scientists still wonder about lots of things in rainforests! Many living things have never even been named, because rainforests are so big and so full of life. Each answer opens ne https://socialmedia.xdme.com/tony/videos-book17/page-150.mp4 https://www.youtube.com/embed/Jn3l97SGDj8 116 2026-10-04T19:29:20+00:00 yes https://xdme.com/watch-book18-q001.html https://xdme.com/book18-thumbs/page-001.jpg How Are the Arctic and Antarctica Different? The Arctic is an ocean covered with floating ice, and Antarctica is a giant continent of land buried under ice! They sit at opposite ends of Earth, and they are opposites in other https://socialmedia.xdme.com/tony/videos-book18/page-001.mp4 https://www.youtube.com/embed/u5kBwzzL1PY 113 2026-10-04T20:14:40+00:00 yes https://xdme.com/watch-book18-q002.html https://xdme.com/book18-thumbs/page-002.jpg Why Is Antarctica Colder than the Arctic? Antarctica is colder than the Arctic because it is a high continent of land, while the Arctic is a low ocean! Height, land, and water all play a part. https://socialmedia.xdme.com/tony/videos-book18/page-002.mp4 https://www.youtube.com/embed/jQ8KFJ3yfcE 114 2026-10-04T20:14:41+00:00 yes https://xdme.com/watch-book18-q003.html https://xdme.com/book18-thumbs/page-003.jpg Is There Land Under the North Pole? No, there is no land under the North Pole! It sits in the middle of the Arctic Ocean, with deep water below. The ice on top is just floating sea ice. https://socialmedia.xdme.com/tony/videos-book18/page-003.mp4 https://www.youtube.com/embed/1ghVHvRr90w 106 2026-10-04T20:14:43+00:00 yes https://xdme.com/watch-book18-q004.html https://xdme.com/book18-thumbs/page-004.jpg How Thick Is the Ice in Antarctica? The ice in Antarctica is about 1.2 miles thick on average, and in some places almost 3 miles thick! That is a giant frozen blanket on top of a continent. https://socialmedia.xdme.com/tony/videos-book18/page-004.mp4 https://www.youtube.com/embed/cDNABY3cHGc 113 2026-10-04T20:14:44+00:00 yes https://xdme.com/watch-book18-q005.html https://xdme.com/book18-thumbs/page-005.jpg Was Antarctica Ever Warm and Green? Yes, Antarctica was once warm and green! Millions of years ago it had forests, ferns, and animals. Earth's continents move very slowly. https://socialmedia.xdme.com/tony/videos-book18/page-005.mp4 https://www.youtube.com/embed/0wXhqy0stb8 116 2026-10-04T20:14:54+00:00 yes https://xdme.com/watch-book18-q006.html https://xdme.com/book18-thumbs/page-006.jpg What Are the Arctic Circle and the Antarctic Circle? The Arctic Circle and the Antarctic Circle are imaginary lines around Earth, about 66.5 degrees north and south of the equator! Inside them, the Sun behaves in a special way. https://socialmedia.xdme.com/tony/videos-book18/page-006.mp4 https://www.youtube.com/embed/OUdqy4qa-dM 113 2026-10-04T20:14:55+00:00 yes https://xdme.com/watch-book18-q007.html https://xdme.com/book18-thumbs/page-007.jpg What Is the Arctic Ocean Like? The Arctic Ocean is the smallest and shallowest ocean on Earth, and it is covered with sea ice in winter! It sits at the top of the world, surrounded by land. https://socialmedia.xdme.com/tony/videos-book18/page-007.mp4 https://www.youtube.com/embed/yKRJrAaDXVk 108 2026-10-04T20:14:56+00:00 yes https://xdme.com/watch-book18-q008.html https://xdme.com/book18-thumbs/page-008.jpg What Is the Southern Ocean? The Southern Ocean is the ring of cold water that circles Antarctica, and many scientists call it the fifth ocean! It has strong winds and giant waves. Let's sail in. https://socialmedia.xdme.com/tony/videos-book18/page-008.mp4 https://www.youtube.com/embed/lT-WvvhjOmM 119 2026-10-04T20:14:58+00:00 yes https://xdme.com/watch-book18-q009.html https://xdme.com/book18-thumbs/page-009.jpg Why Is the Ground Frozen All Year in Parts of the Arctic? In parts of the Arctic, the ground stays frozen all year! It is called permafrost. Only the top layer thaws in summer. Permafrost covers about a quarter of the land in the Northern https://socialmedia.xdme.com/tony/videos-book18/page-009.mp4 https://www.youtube.com/embed/36egqretVa4 118 2026-10-04T20:14:59+00:00 yes https://xdme.com/watch-book18-q010.html https://xdme.com/book18-thumbs/page-010.jpg Why Are There No Tall Trees on the Arctic Tundra? There are no tall trees on the Arctic tundra because it is too cold, too windy, and the ground is frozen below the surface! So plants stay small and low. https://socialmedia.xdme.com/tony/videos-book18/page-010.mp4 https://www.youtube.com/embed/Ygf2BDiY19E 119 2026-10-04T20:15:01+00:00 yes https://xdme.com/watch-book18-q011.html https://xdme.com/book18-thumbs/page-011.jpg What Is the Difference Between Sea Ice and an Ice Sheet? Sea ice is frozen seawater that floats, and an ice sheet is a giant thick layer of ice sitting on land! They are both ice, but they are very different. Let's compare. https://socialmedia.xdme.com/tony/videos-book18/page-011.mp4 https://www.youtube.com/embed/dDE0WV5qQJU 109 2026-10-04T20:15:02+00:00 yes https://xdme.com/watch-book18-q012.html https://xdme.com/book18-thumbs/page-012.jpg How Does Ocean Water Turn Into a Sheet of Ice? Ocean water turns into ice when it gets cold enough, but salty water needs to be colder than freshwater to freeze! Tiny crystals start the process. Let's watch it happen. https://socialmedia.xdme.com/tony/videos-book18/page-012.mp4 https://www.youtube.com/embed/35_7cK4Vi5k 123 2026-10-04T20:15:04+00:00 yes https://xdme.com/watch-book18-q013.html https://xdme.com/book18-thumbs/page-013.jpg Why Is Old Sea Ice Less Salty than the Ocean It Came From? Old sea ice is less salty than the ocean it came from because the salt slowly drains out of it! Over time, the ice becomes much fresher. Let's follow the salt. https://socialmedia.xdme.com/tony/videos-book18/page-013.mp4 https://www.youtube.com/embed/1j9g9R2lHOI 112 2026-10-04T20:15:05+00:00 yes https://xdme.com/watch-book18-q014.html https://xdme.com/book18-thumbs/page-014.jpg Why Do Pancakes of Ice Form on the Ocean? Pancakes of ice form when waves bump and rub slushy ice into round plates! They look just like pancakes floating on the sea. Let's flip through the steps. https://socialmedia.xdme.com/tony/videos-book18/page-014.mp4 https://www.youtube.com/embed/AuF5TYEn0wM 111 2026-10-04T20:15:07+00:00 yes https://xdme.com/watch-book18-q015.html https://xdme.com/book18-thumbs/page-015.jpg What Is an Ice Shelf? An ice shelf is a thick, floating platform of ice that is attached to the land! It sticks out over the sea like a giant frozen shelf. https://socialmedia.xdme.com/tony/videos-book18/page-015.mp4 https://www.youtube.com/embed/V9PUV-os38M 108 2026-10-04T20:15:08+00:00 yes https://xdme.com/watch-book18-q016.html https://xdme.com/book18-thumbs/page-016.jpg Where Do Icebergs Come From? Icebergs come from glaciers and ice shelves that break off into the sea in a process called calving! That is how giant floating ice mountains are born. Let's follow one. https://socialmedia.xdme.com/tony/videos-book18/page-016.mp4 https://www.youtube.com/embed/8vEY2TThKWw 116 2026-10-04T20:15:10+00:00 yes https://xdme.com/watch-book18-q017.html https://xdme.com/book18-thumbs/page-017.jpg Why Are Some Icebergs Flat Like Tables? Some icebergs are flat like tables because they break off ice shelves, which are flat on top! Scientists call them tabular icebergs. https://socialmedia.xdme.com/tony/videos-book18/page-017.mp4 https://www.youtube.com/embed/strfgfdxDmQ 114 2026-10-04T20:15:12+00:00 yes https://xdme.com/watch-book18-q018.html https://xdme.com/book18-thumbs/page-018.jpg Why Do Some Icebergs Look Blue? Some icebergs look blue because very old, tightly packed ice soaks up the red part of sunlight and sends the blue back to your eyes! Bubbles change the color. https://socialmedia.xdme.com/tony/videos-book18/page-018.mp4 https://www.youtube.com/embed/vFASFCiSUSk 106 2026-10-04T20:16:31+00:00 yes https://xdme.com/watch-book18-q019.html https://xdme.com/book18-thumbs/page-019.jpg How Much of an Iceberg Is Hidden Underwater? About nine tenths of an iceberg is hidden underwater, and only the tip shows! That is why people say 'tip of the iceberg'. Let's dive in. https://socialmedia.xdme.com/tony/videos-book18/page-019.mp4 https://www.youtube.com/embed/i3FHisMtCgo 115 2026-10-04T20:17:04+00:00 yes https://xdme.com/watch-book18-q020.html https://xdme.com/book18-thumbs/page-020.jpg Why Does Ice Ooze Downhill Like Thick Honey? Ice looks solid, but under its own huge weight it can slowly flow downhill like thick honey! Rivers of ice carry it toward the sea. https://socialmedia.xdme.com/tony/videos-book18/page-020.mp4 https://www.youtube.com/embed/sh078iPbSsY 111 2026-10-04T20:20:07+00:00 yes https://xdme.com/watch-book18-q021.html https://xdme.com/book18-thumbs/page-021.jpg What Is the Greenland Ice Sheet? The Greenland ice sheet is a giant layer of ice that covers about four fifths of Greenland, the biggest island on Earth! It is up to two miles thick. https://socialmedia.xdme.com/tony/videos-book18/page-021.mp4 https://www.youtube.com/embed/Ucmfo_4FZqo 107 2026-10-04T20:22:41+00:00 yes https://xdme.com/watch-book18-q022.html https://xdme.com/book18-thumbs/page-022.jpg Why Do Giant Cracks Open in Polar Ice? Giant cracks open in polar ice when glaciers stretch and bend as they flow! They are called crevasses. They can be very dangerous. https://socialmedia.xdme.com/tony/videos-book18/page-022.mp4 https://www.youtube.com/embed/MgWEX2lbWtw 120 2026-10-04T20:25:44+00:00 yes https://xdme.com/watch-book18-q023.html https://xdme.com/book18-thumbs/page-023.jpg Where Is the Coldest Place on Earth? The coldest place on Earth is Antarctica! Vostok Station there recorded minus 128.6 degrees Fahrenheit in 1983. At that temperature, your breath would freeze into tiny crystals in https://socialmedia.xdme.com/tony/videos-book18/page-023.mp4 https://www.youtube.com/embed/hkCzJCdlcjA 127 2026-10-04T20:28:48+00:00 yes https://xdme.com/watch-book18-q024.html https://xdme.com/book18-thumbs/page-024.jpg Why Is Antarctica So Windy? Antarctica is so windy because cold, heavy air slides downhill off the high ice sheet like water flowing down a slope! Scientists call these katabatic winds. Hold on to your hat. https://socialmedia.xdme.com/tony/videos-book18/page-024.mp4 https://www.youtube.com/embed/tqVVN6hhgKE 119 2026-10-04T20:31:20+00:00 yes https://xdme.com/watch-book18-q025.html https://xdme.com/book18-thumbs/page-025.jpg Why Are Some Valleys in Antarctica Free of Ice and Snow? Some valleys in Antarctica have no ice or snow because mountains block the glaciers and strong winds blow the snow away! They are called the McMurdo Dry Valleys. Let's visit. https://socialmedia.xdme.com/tony/videos-book18/page-025.mp4 https://www.youtube.com/embed/uaoxVnIMj_c 112 2026-10-04T20:34:05+00:00 yes https://xdme.com/watch-book18-q026.html https://xdme.com/book18-thumbs/page-026.jpg What Is the Midnight Sun? The midnight Sun is when the Sun stays above the horizon all night long in summer! It happens in places north of the Arctic Circle. Let's soak up some sunshine. https://socialmedia.xdme.com/tony/videos-book18/page-026.mp4 https://www.youtube.com/embed/IFVScsvg88I 116 2026-10-04T20:36:41+00:00 yes https://xdme.com/watch-book18-q027.html https://xdme.com/book18-thumbs/page-027.jpg What Is the Polar Night? The polar night is a time in winter when the Sun does not rise at all! Near the pole, it lasts for months. But it is not as dark as you might think. https://socialmedia.xdme.com/tony/videos-book18/page-027.mp4 https://www.youtube.com/embed/HgR7ciSguvM 111 2026-10-04T20:39:43+00:00 yes https://xdme.com/watch-book18-q028.html https://xdme.com/book18-thumbs/page-028.jpg Why Does the Sun Stay Up for Months Near the Poles? The Sun stays up for months near the poles because Earth is tilted as it travels around the Sun! The tilt is about 23.5 degrees. When it is summer at one pole, it is winter at the https://socialmedia.xdme.com/tony/videos-book18/page-028.mp4 https://www.youtube.com/embed/_fivmzvLZPw 109 2026-10-04T20:42:16+00:00 yes https://xdme.com/watch-book18-q029.html https://xdme.com/book18-thumbs/page-029.jpg How Long Is One Day at the North Pole? One day at the North Pole lasts a whole year! There is only one sunrise and one sunset each year. It sounds strange, but it is true. https://socialmedia.xdme.com/tony/videos-book18/page-029.mp4 https://www.youtube.com/embed/ixMZWocti_s 110 2026-10-04T20:45:18+00:00 yes https://xdme.com/watch-book18-q030.html https://xdme.com/book18-thumbs/page-030.jpg Why Does the Sun Circle Around the Sky at the Poles Instead of Rising and Setting? At the poles, the Sun circles the sky instead of rising and setting, because Earth's spin does not carry you through day and night there! It travels around the horizon. Let's spin https://socialmedia.xdme.com/tony/videos-book18/page-030.mp4 https://www.youtube.com/embed/z8X7nyHa8vc 114 2026-10-04T20:47:51+00:00 yes https://xdme.com/watch-book18-q031.html https://xdme.com/book18-thumbs/page-031.jpg Why Is the Sun So Low and Weak Near the Poles? The Sun is low and weak near the poles because its light hits the ground at a slant and spreads out thin! Even in summer, the Sun never climbs high. Let's shine a light on it. https://socialmedia.xdme.com/tony/videos-book18/page-031.mp4 https://www.youtube.com/embed/CU9OP5dRouo 107 2026-10-04T20:50:23+00:00 yes https://xdme.com/watch-book18-q032.html https://xdme.com/book18-thumbs/page-032.jpg What Does the Sky Look Like in the Blue Glow of Polar Twilight? Polar twilight glows in deep blue, purple, and pink before the Sun returns and after it leaves! It can last for days or even weeks. Let's gaze at the sky. https://socialmedia.xdme.com/tony/videos-book18/page-032.mp4 https://www.youtube.com/embed/s_d8B66dICU 112 2026-10-04T20:53:30+00:00 yes https://xdme.com/watch-book18-q033.html https://xdme.com/book18-thumbs/page-033.jpg How Do People Sleep When the Sun Never Sets? People sleep when the Sun never sets by keeping a regular bedtime and making their bedrooms dark! Our bodies have a clock that follows light. Let's learn bedtime tricks. https://socialmedia.xdme.com/tony/videos-book18/page-033.mp4 https://www.youtube.com/embed/o3S4TipWy7E 111 2026-10-04T20:56:03+00:00 yes https://xdme.com/watch-book18-q034.html https://xdme.com/book18-thumbs/page-034.jpg How Do People Living in the Arctic Stay Cheerful During Months of Darkness? People in the Arctic stay cheerful during months of darkness by spending time together, staying active, and using lots of cozy light! Good habits keep spirits bright. https://socialmedia.xdme.com/tony/videos-book18/page-034.mp4 https://www.youtube.com/embed/kK3itHA00Do 116 2026-10-04T20:58:45+00:00 yes https://xdme.com/watch-book18-q035.html https://xdme.com/book18-thumbs/page-035.jpg Why Do Plants Grow So Fast in the Arctic Summer? Plants grow so fast in the Arctic summer because the midnight Sun gives them light almost around the clock! They race to grow before winter comes back. Let's watch them grow. https://socialmedia.xdme.com/tony/videos-book18/page-035.mp4 https://www.youtube.com/embed/nQVFboCW4Ng 123 2026-10-04T21:01:48+00:00 yes https://xdme.com/watch-book18-q036.html https://xdme.com/book18-thumbs/page-036.jpg Why Do Some Arctic Flowers Turn to Follow the Sun? Some Arctic flowers turn to follow the Sun because their cup-shaped petals act like tiny satellite dishes that gather warmth! This sun tracking is called heliotropism. Let's follow https://socialmedia.xdme.com/tony/videos-book18/page-036.mp4 https://www.youtube.com/embed/_fspHDfh7_U 117 2026-10-04T21:04:51+00:00 yes https://xdme.com/watch-book18-q037.html https://xdme.com/book18-thumbs/page-037.jpg Why Don’t Reindeer Follow a Day-And-Night Clock in the Arctic? Scientists found that reindeer in the Arctic do not have a strong 24-hour body rhythm! Instead of following day and night, they eat and rest in short cycles. Let's follow the herd. https://socialmedia.xdme.com/tony/videos-book18/page-037.mp4 https://www.youtube.com/embed/u29YODhOm_c 116 2026-10-04T21:07:54+00:00 yes https://xdme.com/watch-book18-q038.html https://xdme.com/book18-thumbs/page-038.jpg What Do Animals Do During the Long Polar Night? During the long polar night, animals do different things! Some leave, some sleep deeply, and some stay active. Each plan helps them survive. https://socialmedia.xdme.com/tony/videos-book18/page-038.mp4 https://www.youtube.com/embed/RGGxWWQDjV4 115 2026-10-04T21:10:28+00:00 yes https://xdme.com/watch-book18-q039.html https://xdme.com/book18-thumbs/page-039.jpg Why Are Arctic Summers So Full of Mosquitoes? Arctic summers are full of mosquitoes because thawed ground makes thousands of shallow ponds where mosquito eggs hatch! The swarms come out all at once. Let's follow the buzz. https://socialmedia.xdme.com/tony/videos-book18/page-039.mp4 https://www.youtube.com/embed/AOYS5eJ5dQI 115 2026-10-04T21:13:30+00:00 yes https://xdme.com/watch-book18-q040.html https://xdme.com/book18-thumbs/page-040.jpg How Many Seasons Are There at the Poles? The poles have two main seasons, a long sunny summer and a long dark winter! Spring and autumn are very short. Let's go around the year. https://socialmedia.xdme.com/tony/videos-book18/page-040.mp4 https://www.youtube.com/embed/a8ZnAV3M-BA 112 2026-10-04T21:16:03+00:00 yes https://xdme.com/watch-book18-q041.html https://xdme.com/book18-thumbs/page-041.jpg What Is Diamond Dust? Diamond dust is made of tiny ice crystals that form right in the air on very cold, clear days and sparkle as they drift down! It looks like floating glitter. Let's sparkle. https://socialmedia.xdme.com/tony/videos-book18/page-041.mp4 https://www.youtube.com/embed/d4Zv1uYRJl8 117 2026-10-04T21:19:06+00:00 yes https://xdme.com/watch-book18-q042.html https://xdme.com/book18-thumbs/page-042.jpg Why Are Shadows So Long Near the Poles? Shadows are so long near the poles because the Sun sits low in the sky! A low Sun stretches shadows far across the ground. Let's measure. https://socialmedia.xdme.com/tony/videos-book18/page-042.mp4 https://www.youtube.com/embed/BOMlj3yLWeI 112 2026-10-04T21:21:39+00:00 yes https://xdme.com/watch-book18-q043.html https://xdme.com/book18-thumbs/page-043.jpg What Time Is It at the North Pole? At the North Pole, all the time zones meet, so there is no official local time there! Research stations simply choose one that is convenient. Let's check the clock. https://socialmedia.xdme.com/tony/videos-book18/page-043.mp4 https://www.youtube.com/embed/Y_li7oi9piE 112 2026-10-04T21:24:42+00:00 yes https://xdme.com/watch-book18-q044.html https://xdme.com/book18-thumbs/page-044.jpg Why Can Stars Shine All Day During the Polar Night? Stars can shine all day during the polar night because the Sun stays below the horizon, so the sky never brightens! Astronomers love it. Let's stargaze. https://socialmedia.xdme.com/tony/videos-book18/page-044.mp4 https://www.youtube.com/embed/JFn_uIOZec0 118 2026-10-04T21:27:15+00:00 yes https://xdme.com/watch-book18-q045.html https://xdme.com/book18-thumbs/page-045.jpg Why Does the Moon Stay Up for Two Weeks at the Poles? The Moon can stay up for two weeks at the poles because it circles Earth about once a month! Half of that trip is above the horizon. Let's follow the Moon. https://socialmedia.xdme.com/tony/videos-book18/page-045.mp4 https://www.youtube.com/embed/yVcjemoAug0 111 2026-10-04T21:30:00+00:00 yes https://xdme.com/watch-book18-q046.html https://xdme.com/book18-thumbs/page-046.jpg What Happens on the Day the Sun First Returns After the Polar Night? When the Sun first returns after the polar night, it peeks over the horizon for just a few minutes, and people celebrate! Each day, it stays up longer. Let's welcome it back. https://socialmedia.xdme.com/tony/videos-book18/page-046.mp4 https://www.youtube.com/embed/cdf5FM6Djds 114 2026-10-04T21:33:06+00:00 yes https://xdme.com/watch-book18-q047.html https://xdme.com/book18-thumbs/page-047.jpg Why Do Polar Explorers Wear Dark Goggles? Polar explorers wear dark goggles because snow and ice reflect most of the sunlight, and the glare can hurt their eyes! Goggles protect them. Let's gear up. https://socialmedia.xdme.com/tony/videos-book18/page-047.mp4 https://www.youtube.com/embed/9P_4TJjcPZ4 118 2026-10-04T21:36:11+00:00 yes https://xdme.com/watch-book18-q048.html https://xdme.com/book18-thumbs/page-048.jpg Why Does the South Pole Get Less Sunshine Over a Year than a Sunny Beach? The South Pole gets less sunshine over a year than a sunny beach because the Sun is always low there, and it is gone for half the year! Its light is weak and spread out. Let's comp https://socialmedia.xdme.com/tony/videos-book18/page-048.mp4 https://www.youtube.com/embed/qv4LXfDTRI8 110 2026-10-04T21:38:43+00:00 yes https://xdme.com/watch-book18-q049.html https://xdme.com/book18-thumbs/page-049.jpg Why Does the Sun Look Squashed When It Sits Near the Horizon? The Sun looks squashed near the horizon because Earth's air bends its light! The bottom edge bends up more than the top, so the Sun looks flattened like an oval. Let's bend some li https://socialmedia.xdme.com/tony/videos-book18/page-049.mp4 https://www.youtube.com/embed/M52OHZ41nn0 107 2026-10-04T21:41:45+00:00 yes https://xdme.com/watch-book18-q050.html https://xdme.com/book18-thumbs/page-050.jpg How Do Scientists at the South Pole Celebrate the Middle of Winter? At the South Pole, scientists celebrate midwinter on June 21 with a special dinner, cards, and greetings from other stations! It is the darkest day of the year there. Let's join th https://socialmedia.xdme.com/tony/videos-book18/page-050.mp4 https://www.youtube.com/embed/SRvx5e-xFz0 118 2026-10-04T21:44:20+00:00 yes https://xdme.com/watch-book18-q051.html https://xdme.com/book18-thumbs/page-051.jpg How Do Polar Animals Stay Warm Without a Heater? Polar animals wear built-in winter coats made of fur, feathers, and fat! These layers trap heat close to the body, so the cold stays outside. They also use smart shapes and cozy ha https://socialmedia.xdme.com/tony/videos-book18/page-051.mp4 https://www.youtube.com/embed/DGkJO3vC-hE 123 2026-10-04T21:47:23+00:00 yes https://xdme.com/watch-book18-q052.html https://xdme.com/book18-thumbs/page-052.jpg How Do Seals Keep Their Flippers Warm in Icy Water? Seals keep their flippers from wasting heat by using a clever plumbing trick! Warm blood going out to the flipper passes its heat to the cooler blood coming back. So the heat stays https://socialmedia.xdme.com/tony/videos-book18/page-052.mp4 https://www.youtube.com/embed/AEnPFSzQqy4 119 2026-10-04T21:50:26+00:00 yes https://xdme.com/watch-book18-q053.html https://xdme.com/book18-thumbs/page-053.jpg How Can Birds Stand on Ice Without Freezing Their Feet? Birds can stand on ice because their legs have a built-in heat-saving trick! Warm blood heading to the feet gives its heat to cool blood coming back up. So the feet stay cool, but https://socialmedia.xdme.com/tony/videos-book18/page-053.mp4 https://www.youtube.com/embed/ARxb5H4zyss 116 2026-10-04T21:53:28+00:00 yes https://xdme.com/watch-book18-q054.html https://xdme.com/book18-thumbs/page-054.jpg Why Do Many Arctic Animals Have Small Ears and Short Tails? Many Arctic animals have small ears and short tails because small body parts lose less heat! Ears, tails, and legs have lots of surface for their size, and heat escapes through sur https://socialmedia.xdme.com/tony/videos-book18/page-054.mp4 https://www.youtube.com/embed/rzAZ52sYsIg 119 2026-10-04T21:56:08+00:00 yes https://xdme.com/watch-book18-q055.html https://xdme.com/book18-thumbs/page-055.jpg Why Are Polar Animals Often Big and Round? Polar animals are often big and round because a big, round body loses heat slowly! A large body has less skin compared with the amount of body inside. Less skin means less heat can https://socialmedia.xdme.com/tony/videos-book18/page-055.mp4 https://www.youtube.com/embed/yK93HX-RZTA 114 2026-10-04T21:59:11+00:00 yes https://xdme.com/watch-book18-q056.html https://xdme.com/book18-thumbs/page-056.jpg Why Do Snowy Owls Have Feathers on Their Feet? Snowy owls have feathers on their feet to wear built-in fluffy socks! The feathers trap warm air and keep skin from touching cold snow. That helps owls rest on the frozen ground wi https://socialmedia.xdme.com/tony/videos-book18/page-056.mp4 https://www.youtube.com/embed/ldm3invAnuU 116 2026-10-04T22:01:43+00:00 yes https://xdme.com/watch-book18-q057.html https://xdme.com/book18-thumbs/page-057.jpg How Do Reindeer Find Food Under the Snow? Reindeer find food under the snow by smelling it and digging for it! Even under a foot of snow, they can sniff out their winter snack. Then they scrape the snow away with their hoo https://socialmedia.xdme.com/tony/videos-book18/page-057.mp4 https://www.youtube.com/embed/693wx8HFsPg 115 2026-10-04T22:04:46+00:00 yes https://xdme.com/watch-book18-q058.html https://xdme.com/book18-thumbs/page-058.jpg Why Do Reindeer Eyes Turn From Gold to Blue? Reindeer eyes change color with the seasons, from gold in summer to blue in winter! The change helps their eyes see better when the light is very different. It happens in a mirror- https://socialmedia.xdme.com/tony/videos-book18/page-058.mp4 https://www.youtube.com/embed/6UQY-RfKDQM 112 2026-10-04T22:07:22+00:00 yes https://xdme.com/watch-book18-q059.html https://xdme.com/book18-thumbs/page-059.jpg What Makes Musk Ox Wool So Warm? Musk ox wool is so warm because musk oxen wear two coats at once! A long, shaggy outer coat blocks wind and snow. A super-soft wool layer underneath holds in body heat. https://socialmedia.xdme.com/tony/videos-book18/page-059.mp4 https://www.youtube.com/embed/WliXvxwtrhU 114 2026-10-04T22:09:55+00:00 yes https://xdme.com/watch-book18-q060.html https://xdme.com/book18-thumbs/page-060.jpg How Do Lemmings Live Under the Snow? Lemmings live under the snow in a cozy hidden world! When snow piles up, a space forms between the ground and the snow. The snow acts like a blanket, so it stays much warmer than t https://socialmedia.xdme.com/tony/videos-book18/page-060.mp4 https://www.youtube.com/embed/s3FY0V4ebvU 111 2026-10-04T22:12:29+00:00 yes https://xdme.com/watch-book18-q061.html https://xdme.com/book18-thumbs/page-061.jpg How Can Some Fish Live in Water That Is Colder than Freezing? Some fish can live in water colder than freezing because they make their own antifreeze! The antifreeze is made of special proteins in their blood and body fluids. It keeps tiny ic https://socialmedia.xdme.com/tony/videos-book18/page-061.mp4 https://www.youtube.com/embed/-jQjYUkQSFY 126 2026-10-04T22:16:11+00:00 yes https://xdme.com/watch-book18-q062.html https://xdme.com/book18-thumbs/page-062.jpg Why Are Icefish Blood Clear Instead of Red? Icefish blood is clear because icefish do not have red blood cells like most animals! They are special fish that live in the icy waters around Antarctica. Their blood carries oxyge https://socialmedia.xdme.com/tony/videos-book18/page-062.mp4 https://www.youtube.com/embed/-JsUkuvz24o 114 2026-10-04T22:18:12+00:00 yes https://xdme.com/watch-book18-q063.html https://xdme.com/book18-thumbs/page-063.jpg How Can an Arctic Ground Squirrel Survive Below Freezing? Arctic ground squirrels survive below freezing by supercooling their bodies! During hibernation, their body temperature drops to about 27 degrees Fahrenheit. Even so, their body fl https://socialmedia.xdme.com/tony/videos-book18/page-063.mp4 https://www.youtube.com/embed/LwxmOjYIg2k 119 2026-10-04T22:21:15+00:00 yes https://xdme.com/watch-book18-q064.html https://xdme.com/book18-thumbs/page-064.jpg Why Don’t Polar Bear Paws Slip on Ice? Polar bear paws do not slip on ice because they are covered with tiny bumps! The bumps grip the ice like a rubber doormat. And their huge paws spread out the bear's weight, too. https://socialmedia.xdme.com/tony/videos-book18/page-064.mp4 https://www.youtube.com/embed/T5eBIIkW-2s 108 2026-10-04T22:23:47+00:00 yes https://xdme.com/watch-book18-q065.html https://xdme.com/book18-thumbs/page-065.jpg Why Does the Arctic Tern Fly From Pole to Pole? The Arctic tern flies from pole to pole to enjoy two summers every year! It nests in the Arctic summer, then flies south to the Antarctic summer. It follows the sunshine and the fo https://socialmedia.xdme.com/tony/videos-book18/page-065.mp4 https://www.youtube.com/embed/lrOqcsCvH-Y 115 2026-10-04T22:26:50+00:00 yes https://xdme.com/watch-book18-q066.html https://xdme.com/book18-thumbs/page-066.jpg How Deep Can Emperor Penguins Dive? Emperor penguins can dive more than 1,800 feet deep, deeper than a skyscraper is tall! They can also stay underwater for more than 20 minutes. Their bodies have amazing diving tric https://socialmedia.xdme.com/tony/videos-book18/page-066.mp4 https://www.youtube.com/embed/PQHLqrNzIis 121 2026-10-04T22:29:54+00:00 yes https://xdme.com/watch-book18-q067.html https://xdme.com/book18-thumbs/page-067.jpg How Do Seals Breathe Through Holes in the Ice? Seals breathe through holes in the ice that they keep open themselves! They are mammals, so they must come up for air. These holes are their doorways to the air. https://socialmedia.xdme.com/tony/videos-book18/page-067.mp4 https://www.youtube.com/embed/csTTAsINn9A 113 2026-10-04T22:32:25+00:00 yes https://xdme.com/watch-book18-q068.html https://xdme.com/book18-thumbs/page-068.jpg How Do Arctic Hares Hop Across Deep Snow? Arctic hares hop across deep snow on big, furry back feet that work like snowshoes! The wide feet spread out the hare's weight. So the hare stays on top of the snow instead of sink https://socialmedia.xdme.com/tony/videos-book18/page-068.mp4 https://www.youtube.com/embed/dWGD0JSfcyg 110 2026-10-04T22:35:01+00:00 yes https://xdme.com/watch-book18-q069.html https://xdme.com/book18-thumbs/page-069.jpg Why Is the Arctic Willow Shorter than Your Shoe? The Arctic willow is shorter than your shoe because staying low keeps it safe and warm! It is a real willow, but it grows sideways instead of up. Hugging the ground helps it surviv https://socialmedia.xdme.com/tony/videos-book18/page-069.mp4 https://www.youtube.com/embed/LAjXcqcr9s0 110 2026-10-04T22:38:04+00:00 yes https://xdme.com/watch-book18-q070.html https://xdme.com/book18-thumbs/page-070.jpg What Are Lichens, and Why Do They Grow on Bare Polar Rock? A lichen is a team of a fungus and a tiny alga living together! The fungus gives shelter, and the alga makes food from sunlight. Together they can live on bare polar rock where not https://socialmedia.xdme.com/tony/videos-book18/page-070.mp4 https://www.youtube.com/embed/Q0jHNIv3FZg 113 2026-10-04T22:40:37+00:00 yes https://xdme.com/watch-book18-q071.html https://xdme.com/book18-thumbs/page-071.jpg What Are Snow Fleas? Snow fleas are tiny black specks that hop around on the snow, but they are not real fleas! They do not bite people or pets. They are tiny animals called springtails. https://socialmedia.xdme.com/tony/videos-book18/page-071.mp4 https://www.youtube.com/embed/Dw2dhbdanQM 117 2026-10-04T22:43:40+00:00 yes https://xdme.com/watch-book18-q072.html https://xdme.com/book18-thumbs/page-072.jpg Do Worms Really Live in Glaciers? Yes, worms really live in glaciers! They are called ice worms. These tiny black worms spend their whole lives in the ice. Ice worms are among the few animals that live their whole https://socialmedia.xdme.com/tony/videos-book18/page-072.mp4 https://www.youtube.com/embed/omJleRAMQbU 109 2026-10-04T22:46:33+00:00 yes https://xdme.com/watch-book18-q073.html https://xdme.com/book18-thumbs/page-073.jpg Why Do Sled Dogs Curl Up in the Snow to Sleep? Sled dogs curl up in the snow to sleep because it keeps them warm! Their thick coats, curled-up bodies, and bushy tails work together. Even the snow itself helps, like a soft blank https://socialmedia.xdme.com/tony/videos-book18/page-073.mp4 https://www.youtube.com/embed/GuMWwyxtwxA 109 2026-10-04T22:49:06+00:00 yes https://xdme.com/watch-book18-q074.html https://xdme.com/book18-thumbs/page-074.jpg What Are Walrus Tusks For? Walrus tusks are long teeth that help walruses in lots of ways! They keep growing for a walrus's whole life. A walrus can use them like ice picks. https://socialmedia.xdme.com/tony/videos-book18/page-074.mp4 https://www.youtube.com/embed/k4UnRbSCMbA 112 2026-10-04T22:51:39+00:00 yes https://xdme.com/watch-book18-q075.html https://xdme.com/book18-thumbs/page-075.jpg How Do Polar Animals Know When Winter Is Coming? Polar animals know winter is coming by watching how long the days are! The length of the day is the same every year, even when the weather is odd. That makes it a very reliable clu https://socialmedia.xdme.com/tony/videos-book18/page-075.mp4 https://www.youtube.com/embed/DI8svJO4etY 111 2026-10-04T22:54:16+00:00 yes https://xdme.com/watch-book18-q076.html https://xdme.com/book18-thumbs/page-076.jpg Why Are Polar Seas So Full of Life? Polar seas are full of life because cold water is packed with oxygen and nutrients! In summer, the Sun shines almost all day long. That helps tiny floating plants grow in huge numb https://socialmedia.xdme.com/tony/videos-book18/page-076.mp4 https://www.youtube.com/embed/gOsVEUhNpfg 114 2026-10-04T20:15:14+00:00 yes https://xdme.com/watch-book18-q077.html https://xdme.com/book18-thumbs/page-077.jpg What Is Krill, and Why Does It Matter So Much? Krill are small, shrimp-like animals that matter hugely to the Southern Ocean! They eat tiny plants and are eaten by almost everyone. Let's learn more! https://socialmedia.xdme.com/tony/videos-book18/page-077.mp4 https://www.youtube.com/embed/gCN1bCS8naM 112 2026-10-04T20:15:16+00:00 yes https://xdme.com/watch-book18-q078.html https://xdme.com/book18-thumbs/page-078.jpg What Lives on the Underside of Sea Ice? Under sea ice lives a hidden garden of tiny plants called ice algae! They grow in brown and golden streaks on the bottom of the ice. Tiny animals graze on them like cows in a meado https://socialmedia.xdme.com/tony/videos-book18/page-078.mp4 https://www.youtube.com/embed/GB1-yzxnr7s 111 2026-10-04T20:15:18+00:00 yes https://xdme.com/watch-book18-q079.html https://xdme.com/book18-thumbs/page-079.jpg Why Is Sea Ice a Nursery for Baby Animals? Sea ice is a nursery because it gives young animals safety, warmth, and food! Many babies are born or grow up on and around the ice. It is a stable place to rest, close to a meal. https://socialmedia.xdme.com/tony/videos-book18/page-079.mp4 https://www.youtube.com/embed/OrNaDKidPbQ 109 2026-10-04T20:15:20+00:00 yes https://xdme.com/watch-book18-q080.html https://xdme.com/book18-thumbs/page-080.jpg Who Eats Whom in the Antarctic Ocean? In the Antarctic ocean, almost everyone eats or is eaten, starting with tiny plants! Krill sit in the middle of the whole web. They are the center of almost everything. https://socialmedia.xdme.com/tony/videos-book18/page-080.mp4 https://www.youtube.com/embed/Tbife0VNVb8 107 2026-10-04T20:15:22+00:00 yes https://xdme.com/watch-book18-q081.html https://xdme.com/book18-thumbs/page-081.jpg What Does the Arctic Food Web Look Like? The Arctic food web starts with tiny algae and plankton and reaches all the way up to polar bears! Each link depends on the one below it. That means a change at the bottom can be f https://socialmedia.xdme.com/tony/videos-book18/page-081.mp4 https://www.youtube.com/embed/CkVo335ZOEA 113 2026-10-04T20:15:41+00:00 yes https://xdme.com/watch-book18-q082.html https://xdme.com/book18-thumbs/page-082.jpg What Are Copepods? Copepods are tiny swimming animals in the sea, and they are cousins of crabs! Each one is only about the size of a grain of rice. But there are so many that they feed huge animals. https://socialmedia.xdme.com/tony/videos-book18/page-082.mp4 https://www.youtube.com/embed/dyk-WdDTdcY 115 2026-10-04T20:15:42+00:00 yes https://xdme.com/watch-book18-q083.html https://xdme.com/book18-thumbs/page-083.jpg Why Do Whales Visit Polar Seas to Eat? Whales visit polar seas to eat because summer there is an enormous buffet! The water is full of krill and fish. Whales feast for months and store up lots of fat. https://socialmedia.xdme.com/tony/videos-book18/page-083.mp4 https://www.youtube.com/embed/IR-P18qCY_k 110 2026-10-04T20:15:45+00:00 yes https://xdme.com/watch-book18-q084.html https://xdme.com/book18-thumbs/page-084.jpg How Can a Bowhead Whale Live for 200 Years? Bowhead whales can live around 200 years, longer than any other mammal! They live in cold water and grow very slowly. Their bodies also seem to repair damage very well. https://socialmedia.xdme.com/tony/videos-book18/page-084.mp4 https://www.youtube.com/embed/W4zXRmsgGoc 114 2026-10-04T20:15:46+00:00 yes https://xdme.com/watch-book18-q085.html https://xdme.com/book18-thumbs/page-085.jpg Why Does the Southern Ocean Circle All the Way Around Antarctica? The Southern Ocean circles Antarctica because no land blocks the water! Strong winds push it around the continent from west to east. It is like a giant merry-go-round of sea. https://socialmedia.xdme.com/tony/videos-book18/page-085.mp4 https://www.youtube.com/embed/oys6RsX3Poo 114 2026-10-04T20:15:48+00:00 yes https://xdme.com/watch-book18-q086.html https://xdme.com/book18-thumbs/page-086.jpg Why Does Sinking Cold, Salty Water Matter for the Ocean? Sinking cold, salty water matters because it carries oxygen and heat all around the ocean! Very cold, salty water is heavy, so it sinks. It then spreads along the sea floor for tho https://socialmedia.xdme.com/tony/videos-book18/page-086.mp4 https://www.youtube.com/embed/t23elIwL7AY 121 2026-10-04T20:15:49+00:00 yes https://xdme.com/watch-book18-q087.html https://xdme.com/book18-thumbs/page-087.jpg Why Are Some Antarctic Sea Creatures So Big? Some Antarctic sea creatures grow extra big, and scientists call this polar gigantism! Sea spiders can be as big as a dinner plate. Scientists are still studying all the reasons. https://socialmedia.xdme.com/tony/videos-book18/page-087.mp4 https://www.youtube.com/embed/id0Fck6KmHI 113 2026-10-04T20:15:52+00:00 yes https://xdme.com/watch-book18-q088.html https://xdme.com/book18-thumbs/page-088.jpg What Is a Brinicle? A brinicle is a hollow tube of ice that grows downward from sea ice! It forms from super-salty, super-cold water called brine. Some people call it an ice stalactite. https://socialmedia.xdme.com/tony/videos-book18/page-088.mp4 https://www.youtube.com/embed/ukzQXo_C-P8 117 2026-10-04T20:15:54+00:00 yes https://xdme.com/watch-book18-q089.html https://xdme.com/book18-thumbs/page-089.jpg What Is a Polynya? A polynya is a patch of open water surrounded by sea ice! It sounds like pol-IN-yah. These watery windows are very important for wildlife. https://socialmedia.xdme.com/tony/videos-book18/page-089.mp4 https://www.youtube.com/embed/Vyv3hBhGdCA 112 2026-10-04T20:15:55+00:00 yes https://xdme.com/watch-book18-q090.html https://xdme.com/book18-thumbs/page-090.jpg How Do Millions of Seabirds Fit on One Arctic Cliff? Millions of seabirds fit on Arctic cliffs by using every tiny ledge! Each pair needs only a small space. The cliffs are safe, and the sea below is full of food. https://socialmedia.xdme.com/tony/videos-book18/page-090.mp4 https://www.youtube.com/embed/KjwpQW8-bQ0 108 2026-10-04T20:15:57+00:00 yes https://xdme.com/watch-book18-q091.html https://xdme.com/book18-thumbs/page-091.jpg Why Do Arctic Bird Cliffs Have Bright Green Grass and Orange Rocks? Arctic bird cliffs are green and orange because seabirds feed the plants without trying! Their droppings work like fertilizer. That makes grass and orange lichens grow lush and bri https://socialmedia.xdme.com/tony/videos-book18/page-091.mp4 https://www.youtube.com/embed/M7JSdUQdcmI 117 2026-10-04T20:15:58+00:00 yes https://xdme.com/watch-book18-q092.html https://xdme.com/book18-thumbs/page-092.jpg How Old Can a Greenland Shark Get? A Greenland shark may live for hundreds of years! Scientists estimate some are 250 to 500 years old. That makes them the longest-living backboned animals known. https://socialmedia.xdme.com/tony/videos-book18/page-092.mp4 https://www.youtube.com/embed/ExYmd_nipKM 118 2026-10-04T20:16:00+00:00 yes https://xdme.com/watch-book18-q093.html https://xdme.com/book18-thumbs/page-093.jpg Do Corals Live in Cold Polar Waters? Yes, corals live in cold polar waters, too! These cold-water corals live deep in the dark sea, where there is no sunlight. They catch their own food instead. https://socialmedia.xdme.com/tony/videos-book18/page-093.mp4 https://www.youtube.com/embed/uSuAEQNx4hM 115 2026-10-04T20:16:32+00:00 yes https://xdme.com/watch-book18-q094.html https://xdme.com/book18-thumbs/page-094.jpg What Are Seal Whiskers For? Seal whiskers are super-sensitive detectors that help seals find fish! They can feel tiny ripples in the water. That works even in the dark. https://socialmedia.xdme.com/tony/videos-book18/page-094.mp4 https://www.youtube.com/embed/rNn66x_mDfo 111 2026-10-04T20:17:05+00:00 yes https://xdme.com/watch-book18-q095.html https://xdme.com/book18-thumbs/page-095.jpg Why Do Some Seals Sing Under the Ice? Some seals sing under the ice because sound travels far in water! Male Weddell seals and bearded seals make long trills and whistles. Their songs can be heard miles away. https://socialmedia.xdme.com/tony/videos-book18/page-095.mp4 https://www.youtube.com/embed/QoizktETJKw 112 2026-10-04T20:20:10+00:00 yes https://xdme.com/watch-book18-q096.html https://xdme.com/book18-thumbs/page-096.jpg Why Is the Edge of the Sea Ice a Feeding Hotspot? The edge of the sea ice is a feeding hotspot because the meltwater there sets off a feast! Fresh meltwater floats on top of the salty sea. That layer is sunny and calm, perfect for https://socialmedia.xdme.com/tony/videos-book18/page-096.mp4 https://www.youtube.com/embed/vEaxcBokJTM 113 2026-10-04T20:22:42+00:00 yes https://xdme.com/watch-book18-q097.html https://xdme.com/book18-thumbs/page-097.jpg How Can Satellites Find Penguins From Space? Satellites can find penguins from space by spotting their droppings! The droppings stain the ice and rocks a reddish brown. That color can be seen from far, far above. https://socialmedia.xdme.com/tony/videos-book18/page-097.mp4 https://www.youtube.com/embed/xJoSCpdiwNo 119 2026-10-04T20:25:46+00:00 yes https://xdme.com/watch-book18-q098.html https://xdme.com/book18-thumbs/page-098.jpg Why Do Polar Animals Grow So Slowly? Polar animals grow slowly because cold slows down the chemistry in their bodies! Many take years to mature and live for decades. Slow growth uses less energy. https://socialmedia.xdme.com/tony/videos-book18/page-098.mp4 https://www.youtube.com/embed/6ivmj00Brto 115 2026-10-04T20:28:17+00:00 yes https://xdme.com/watch-book18-q099.html https://xdme.com/book18-thumbs/page-099.jpg Why Are Polar Seas Busy in Summer and Quiet in Winter? Polar seas are busy in summer and quiet in winter because the Sun brings the food! In summer, nearly nonstop sunshine makes plankton bloom. In winter, there is little light, so the https://socialmedia.xdme.com/tony/videos-book18/page-099.mp4 https://www.youtube.com/embed/bIuexDLRKo8 118 2026-10-04T20:31:34+00:00 yes https://xdme.com/watch-book18-q100.html https://xdme.com/book18-thumbs/page-100.jpg How Do Scientists Explore Under Polar Sea Ice? Scientists explore under polar sea ice using cameras, robots, and special vehicles! These tools let researchers look beneath thick ice. And they do it without breaking the ice open https://socialmedia.xdme.com/tony/videos-book18/page-100.mp4 https://www.youtube.com/embed/-WtvJIPGZgQ 114 2026-10-04T20:34:09+00:00 yes https://xdme.com/watch-book18-q101.html https://xdme.com/book18-thumbs/page-101.jpg How Do Icebreaker Ships Break Through Thick Ice? An icebreaker is a ship built to crush its way through thick ice! It has a super strong steel hull and a bow shaped like a sloping spoon. The engines push it up onto the ice, and i https://socialmedia.xdme.com/tony/videos-book18/page-101.mp4 https://www.youtube.com/embed/zLlBAY8mq_o 116 2026-10-04T20:36:42+00:00 yes https://xdme.com/watch-book18-q102.html https://xdme.com/book18-thumbs/page-102.jpg How Do Ships Find a Path Through Sea Ice? Ships find a path through sea ice by reading clues from the water, the air, and even space! Ice pilots look for open channels, and satellites show where the ice is thick or thin. T https://socialmedia.xdme.com/tony/videos-book18/page-102.mp4 https://www.youtube.com/embed/-sTyaSu1lgg 116 2026-10-04T20:39:44+00:00 yes https://xdme.com/watch-book18-q103.html https://xdme.com/book18-thumbs/page-103.jpg How Do Planes Land on Snow and Ice? Planes land on snow and ice by using skis instead of wheels! Skis spread the plane's weight over a wide area, so it glides on top. Pilots also need a smooth, hard surface to land o https://socialmedia.xdme.com/tony/videos-book18/page-103.mp4 https://www.youtube.com/embed/0bFX6KLilT4 115 2026-10-04T20:42:17+00:00 yes https://xdme.com/watch-book18-q104.html https://xdme.com/book18-thumbs/page-104.jpg What Vehicles Drive Across Polar Snow and Ice? Polar travelers use snowmobiles, tracked vehicles, and big tractors to cross snow and ice! Tracks and wide skis spread out weight so vehicles do not sink. Some pull sleds loaded wi https://socialmedia.xdme.com/tony/videos-book18/page-104.mp4 https://www.youtube.com/embed/Mrg9TY_Vc1E 117 2026-10-04T20:45:20+00:00 yes https://xdme.com/watch-book18-q105.html https://xdme.com/book18-thumbs/page-105.jpg Why Don’t Skis Sink Into the Snow? Skis do not sink because they spread your weight over a big area! Your weight is the same, but the push on each bit of snow is much smaller. Scientists call that push pressure, and https://socialmedia.xdme.com/tony/videos-book18/page-105.mp4 https://www.youtube.com/embed/lgFCbvMNn1A 111 2026-10-04T20:47:52+00:00 yes https://xdme.com/watch-book18-q106.html https://xdme.com/book18-thumbs/page-106.jpg Why Do Polar Travelers Wear Layers of Clothes? Polar travelers wear layers because layers trap warm air between them! Each layer has its own job, and together they keep the cold out. Layers also let you adjust as you warm up or https://socialmedia.xdme.com/tony/videos-book18/page-106.mp4 https://www.youtube.com/embed/Veh9aDaEkLA 111 2026-10-04T20:50:56+00:00 yes https://xdme.com/watch-book18-q107.html https://xdme.com/book18-thumbs/page-107.jpg Do People Really Live in Igloos? Not really! Most people today live in regular houses, but snow houses are real! Inuit in the Canadian Arctic have built snow houses for hundreds of years. https://socialmedia.xdme.com/tony/videos-book18/page-107.mp4 https://www.youtube.com/embed/y2S9FUFxAVY 115 2026-10-04T20:53:31+00:00 yes https://xdme.com/watch-book18-q108.html https://xdme.com/book18-thumbs/page-108.jpg What Is It Like to Live in a Polar Base? A polar research station is like a small town in the ice! It has bedrooms, a kitchen, labs, a gym, and places to relax. Scientists, cooks, mechanics, and doctors all live and work https://socialmedia.xdme.com/tony/videos-book18/page-108.mp4 https://www.youtube.com/embed/CIKLvFlqy24 112 2026-10-04T20:56:07+00:00 yes https://xdme.com/watch-book18-q109.html https://xdme.com/book18-thumbs/page-109.jpg Where Do Polar Stations Get Their Electricity? Most polar stations make electricity with generators that burn special fuel! Some also use sunshine and wind, when they can. Every drop of fuel has to be shipped in, so energy is p https://socialmedia.xdme.com/tony/videos-book18/page-109.mp4 https://www.youtube.com/embed/gwWtEFYutYI 114 2026-10-04T20:59:16+00:00 yes https://xdme.com/watch-book18-q110.html https://xdme.com/book18-thumbs/page-110.jpg Where Does Drinking Water Come From When Everything Is Frozen? Even where everything is frozen, polar stations make their own drinking water! There is plenty of ice, but there are no taps. So crews melt clean ice and snow, or take water from t https://socialmedia.xdme.com/tony/videos-book18/page-110.mp4 https://www.youtube.com/embed/mW4PM_2ZM9g 112 2026-10-04T21:01:50+00:00 yes https://xdme.com/watch-book18-q111.html https://xdme.com/book18-thumbs/page-111.jpg What Do Polar Scientists Eat All Winter? Polar scientists eat well all winter, thanks to careful planning! Chefs plan the menus months ahead and store lots of frozen, canned, and dried food. Some stations even grow fresh https://socialmedia.xdme.com/tony/videos-book18/page-111.mp4 https://www.youtube.com/embed/TeowICWxoZM 119 2026-10-04T21:04:52+00:00 yes https://xdme.com/watch-book18-q112.html https://xdme.com/book18-thumbs/page-112.jpg What Happens to Trash in Antarctica? In Antarctica, nothing is left behind! There are strict rules: stations must take their waste back out. That keeps the cleanest continent clean. https://socialmedia.xdme.com/tony/videos-book18/page-112.mp4 https://www.youtube.com/embed/vHByW-TIoTc 116 2026-10-04T21:07:56+00:00 yes https://xdme.com/watch-book18-q113.html https://xdme.com/book18-thumbs/page-113.jpg Why Was Halley Vi Research Station Built on Giant Skis? Halley VI sits on a floating ice shelf in Antarctica, where snow keeps piling up and ice keeps moving! So its builders put the station on giant skis and legs. That way it can rise https://socialmedia.xdme.com/tony/videos-book18/page-113.mp4 https://www.youtube.com/embed/-66CTwdqnwE 116 2026-10-04T21:10:29+00:00 yes https://xdme.com/watch-book18-q114.html https://xdme.com/book18-thumbs/page-114.jpg Why Are Some Polar Buildings Built Up on Stilts? Some polar buildings stand on stilts so they do not melt the ground or get buried! In places with permafrost, a heated building can melt the frozen ground below it. Then it would s https://socialmedia.xdme.com/tony/videos-book18/page-114.mp4 https://www.youtube.com/embed/oa4cvNMYDhg 116 2026-10-04T21:13:32+00:00 yes https://xdme.com/watch-book18-q115.html https://xdme.com/book18-thumbs/page-115.jpg How Do Polar Scientists Call Home? Polar scientists call home using radio and satellites! Signals travel up to a satellite and back down to Earth. Near the poles, that can be a little slow. https://socialmedia.xdme.com/tony/videos-book18/page-115.mp4 https://www.youtube.com/embed/O-qRMUJYAOI 115 2026-10-04T21:16:35+00:00 yes https://xdme.com/watch-book18-q116.html https://xdme.com/book18-thumbs/page-116.jpg How Do Polar Travelers Stay Safe? Polar travelers stay safe by training first, planning well, and never going alone! They carry the right gear and always tell the station where they are going. Safety is the first r https://socialmedia.xdme.com/tony/videos-book18/page-116.mp4 https://www.youtube.com/embed/2Qyyy13SHS4 112 2026-10-04T21:19:08+00:00 yes https://xdme.com/watch-book18-q117.html https://xdme.com/book18-thumbs/page-117.jpg Why Do Batteries and Metal Act Strangely in Extreme Cold? Extreme cold changes how things work, especially batteries and some materials! Cold slows the chemical reactions that make a battery work, just like cold honey flows slowly. So pho https://socialmedia.xdme.com/tony/videos-book18/page-117.mp4 https://www.youtube.com/embed/Vq8lvg21Qv0 117 2026-10-04T21:21:40+00:00 yes https://xdme.com/watch-book18-q118.html https://xdme.com/book18-thumbs/page-118.jpg Why Do Eyelashes and Beards Get Frosty in the Cold? Frosty eyelashes and beards come from your own warm breath! Your breath is full of invisible water vapor, which is water in the form of a gas. When it meets freezing air, it turns https://socialmedia.xdme.com/tony/videos-book18/page-118.mp4 https://www.youtube.com/embed/6kcxw2WStmA 114 2026-10-04T21:24:43+00:00 yes https://xdme.com/watch-book18-q119.html https://xdme.com/book18-thumbs/page-119.jpg Why Do Scientists Put Giant Telescopes at the South Pole? The South Pole is a super place for telescopes! It is high, very cold, and extremely dry, so the air is clear and steady. And the ice itself can become part of the instrument. https://socialmedia.xdme.com/tony/videos-book18/page-119.mp4 https://www.youtube.com/embed/F1qX2wGJTeE 116 2026-10-04T21:27:28+00:00 yes https://xdme.com/watch-book18-q120.html https://xdme.com/book18-thumbs/page-120.jpg How Do Weather Balloons Help Polar Scientists? Weather balloons carry instruments high into the sky for polar scientists! Station staff release them every day. The instruments measure the air as the balloon climbs. https://socialmedia.xdme.com/tony/videos-book18/page-120.mp4 https://www.youtube.com/embed/a0cbdyRre0o 119 2026-10-04T21:30:01+00:00 yes https://xdme.com/watch-book18-q121.html https://xdme.com/book18-thumbs/page-121.jpg What Is a Research Ship That Spends a Year Frozen in the Ice? It is a research ship that froze into the Arctic ice on purpose and drifted for about a year! The German ship Polarstern did this in 2019, so scientists could study the Arctic thro https://socialmedia.xdme.com/tony/videos-book18/page-121.mp4 https://www.youtube.com/embed/l55VRaVOzpA 120 2026-10-04T21:33:07+00:00 yes https://xdme.com/watch-book18-q122.html https://xdme.com/book18-thumbs/page-122.jpg What Are Ice Roads? Ice roads are roads made right on top of frozen lakes and rivers in winter! In northern Canada, the ice gets thick enough to carry heavy trucks. When spring comes, the road melts a https://socialmedia.xdme.com/tony/videos-book18/page-122.mp4 https://www.youtube.com/embed/CodnDNzIQfA 110 2026-10-04T21:35:39+00:00 yes https://xdme.com/watch-book18-q123.html https://xdme.com/book18-thumbs/page-123.jpg Why Do Compasses Go Haywire Near the Poles? A compass points to Earth's magnetic poles, and those are not the same as the geographic poles! Near the magnetic North Pole, the needle can tilt and wander. That is why explorers https://socialmedia.xdme.com/tony/videos-book18/page-123.mp4 https://www.youtube.com/embed/QaMpob4LYxU 113 2026-10-04T21:38:44+00:00 yes https://xdme.com/watch-book18-q124.html https://xdme.com/book18-thumbs/page-124.jpg Can You Grow Vegetables in the Polar Winter? Yes, you can grow vegetables in the polar winter, if you grow them indoors! Some polar stations have special greenhouses with glowing pink lights. The plants never need sunshine or https://socialmedia.xdme.com/tony/videos-book18/page-124.mp4 https://www.youtube.com/embed/CuuW62L9YBU 115 2026-10-04T21:41:49+00:00 yes https://xdme.com/watch-book18-q125.html https://xdme.com/book18-thumbs/page-125.jpg How Do Supplies Reach the Bottom of the World? Supplies reach the bottom of the world by ship, plane, and long overland tractor trips! Each way has its own job, and the weather decides the schedule. Together, they keep the stat https://socialmedia.xdme.com/tony/videos-book18/page-125.mp4 https://www.youtube.com/embed/HNFevoQ0FzQ 115 2026-10-04T21:44:22+00:00 yes https://xdme.com/watch-book18-q126.html https://xdme.com/book18-thumbs/page-126.jpg Why Does Old Glacier Ice Fizz and Pop When It Melts? Old glacier ice fizzes and pops because it holds tiny bubbles of ancient air! Those bubbles were squeezed in when the ice formed, under high pressure. When the ice melts, the air b https://socialmedia.xdme.com/tony/videos-book18/page-126.mp4 https://www.youtube.com/embed/UErur3tyIjM 113 2026-10-04T21:47:24+00:00 yes https://xdme.com/watch-book18-q127.html https://xdme.com/book18-thumbs/page-127.jpg How Do Satellites Measure Ice From Space? Satellites measure ice from space using laser light and radar! They time how long a signal takes to bounce back from the ground. That tells scientists how high the ice is. https://socialmedia.xdme.com/tony/videos-book18/page-127.mp4 https://www.youtube.com/embed/AP6fjkbddgs 118 2026-10-04T21:50:27+00:00 yes https://xdme.com/watch-book18-q128.html https://xdme.com/book18-thumbs/page-128.jpg How Do Scientists Use GPS to Watch Ice Move? Scientists place GPS stations on glaciers to watch how the ice moves! Each station records its own position, all the time. So scientists can see exactly how far it travels. https://socialmedia.xdme.com/tony/videos-book18/page-128.mp4 https://www.youtube.com/embed/uSc3wGL0BrQ 115 2026-10-04T21:53:30+00:00 yes https://xdme.com/watch-book18-q129.html https://xdme.com/book18-thumbs/page-129.jpg How Can Radar See Through Ice? Radar can see through ice because radio waves travel through it! The waves bounce off the rock below and come back as echoes. Timing the echoes shows how thick the ice is. https://socialmedia.xdme.com/tony/videos-book18/page-129.mp4 https://www.youtube.com/embed/ZoDD9KvTpg4 111 2026-10-04T21:56:09+00:00 yes https://xdme.com/watch-book18-q130.html https://xdme.com/book18-thumbs/page-130.jpg Are There Lakes Hidden Under Antarctic Ice? Yes! Hundreds of lakes are hidden deep under the Antarctic ice! The water stays liquid even though the surface is freezing. Lake Vostok is under more than 2 miles of ice. https://socialmedia.xdme.com/tony/videos-book18/page-130.mp4 https://www.youtube.com/embed/7QLu0ldCfHE 113 2026-10-04T21:59:12+00:00 yes https://xdme.com/watch-book18-q131.html https://xdme.com/book18-thumbs/page-131.jpg Is There a Volcano in Antarctica? Yes! Antarctica has a volcano, and it is still active! Mount Erebus on Ross Island is the southernmost active volcano on Earth. Mount Erebus is about 12,400 feet tall. https://socialmedia.xdme.com/tony/videos-book18/page-131.mp4 https://www.youtube.com/embed/OZODr4w3z1I 118 2026-10-04T22:01:45+00:00 yes https://xdme.com/watch-book18-q132.html https://xdme.com/book18-thumbs/page-132.jpg Why Are Melt Ponds on Ice So Bright Blue? Melt ponds are bright blue because water soaks up red light and scatters blue light! The white ice below bounces the light back up. That makes the pools glow like swimming pools. https://socialmedia.xdme.com/tony/videos-book18/page-132.mp4 https://www.youtube.com/embed/mK8W4kcsDfw 111 2026-10-04T22:04:48+00:00 yes https://xdme.com/watch-book18-q133.html https://xdme.com/book18-thumbs/page-133.jpg What Is a Moulin? A moulin is a deep, narrow shaft in a glacier where meltwater pours down! The word moulin means mill in French. It acts like a giant drain in the ice, carrying water to the bottom. https://socialmedia.xdme.com/tony/videos-book18/page-133.mp4 https://www.youtube.com/embed/bRc0s8lsoW8 112 2026-10-04T22:07:24+00:00 yes https://xdme.com/watch-book18-q134.html https://xdme.com/book18-thumbs/page-134.jpg Why Does Melting Land Ice Raise Sea Level but Melting Sea Ice Does Not? Melting land ice raises sea level, but melting sea ice hardly does! Sea ice already floats in the water, and it takes up as much space as it weighs. Ice on land is not in the water https://socialmedia.xdme.com/tony/videos-book18/page-134.mp4 https://www.youtube.com/embed/Jvx5FQOqIyU 112 2026-10-04T22:09:58+00:00 yes https://xdme.com/watch-book18-q135.html https://xdme.com/book18-thumbs/page-135.jpg Why Does White Ice Help Cool the Planet? White ice works like a giant mirror for the planet! Bright snow and ice reflect most of the sunlight that hits them, like a mirror does. That sends the heat back into space. https://socialmedia.xdme.com/tony/videos-book18/page-135.mp4 https://www.youtube.com/embed/4gglIAINnpM 114 2026-10-04T22:13:00+00:00 yes https://xdme.com/watch-book18-q136.html https://xdme.com/book18-thumbs/page-136.jpg Why Are the Poles Warming Faster than the Rest of the World? Scientists measure that the Arctic is warming faster than the rest of the planet. One big reason is a loop, where melting ice leads to even more melting. Researchers keep measuring https://socialmedia.xdme.com/tony/videos-book18/page-136.mp4 https://www.youtube.com/embed/Lvm3vXPsu7c 118 2026-10-04T22:15:32+00:00 yes https://xdme.com/watch-book18-q137.html https://xdme.com/book18-thumbs/page-137.jpg What Happens to Seals and Seabirds When Sea Ice Shrinks? Seals, seabirds, and other animals use sea ice, so changes in the ice mean changes for them. When the ice forms later or melts earlier, animals may need to adapt. Scientists watch https://socialmedia.xdme.com/tony/videos-book18/page-137.mp4 https://www.youtube.com/embed/NctrfvGl8DY 116 2026-10-04T22:18:44+00:00 yes https://xdme.com/watch-book18-q138.html https://xdme.com/book18-thumbs/page-138.jpg What Is the Difference Between Old and New Arctic Ice? New Arctic ice formed this winter, and old ice has survived at least one summer. They look different, and they act differently too. Scientists keep track of how much of each there https://socialmedia.xdme.com/tony/videos-book18/page-138.mp4 https://www.youtube.com/embed/MT2AlPxGNJI 111 2026-10-04T22:21:16+00:00 yes https://xdme.com/watch-book18-q139.html https://xdme.com/book18-thumbs/page-139.jpg Can a Flower Bloom Again After 30,000 Years Frozen? Yes! Scientists grew a flower from a fruit that was frozen for about 30,000 years! It was buried in frozen ground in Siberia, by an Ice Age squirrel. https://socialmedia.xdme.com/tony/videos-book18/page-139.mp4 https://www.youtube.com/embed/RGNJPuSeQ7w 115 2026-10-04T22:24:19+00:00 yes https://xdme.com/watch-book18-q140.html https://xdme.com/book18-thumbs/page-140.jpg How Do Time-Lapse Cameras Watch Glaciers? Time-lapse cameras turn slow glacier changes into a fast movie! They take a photo every hour for years. Then scientists play the pictures back quickly. https://socialmedia.xdme.com/tony/videos-book18/page-140.mp4 https://www.youtube.com/embed/rkASyAnsJDg 116 2026-10-04T22:26:51+00:00 yes https://xdme.com/watch-book18-q141.html https://xdme.com/book18-thumbs/page-141.jpg How Do Seals Help Scientists Study the Ocean? Seals help scientists by carrying tiny sensors into places no ship can go! The sensors measure the ocean while the seal swims and dives. Then they send the data to scientists by sa https://socialmedia.xdme.com/tony/videos-book18/page-141.mp4 https://www.youtube.com/embed/fcmos__puZI 115 2026-10-04T22:29:23+00:00 yes https://xdme.com/watch-book18-q142.html https://xdme.com/book18-thumbs/page-142.jpg How Do Robots and Flying Machines Help Scientists on the Ice? Robots and flying machines go where it is too cold or risky for people! They send back pictures and measurements to the scientists. That helps scientists learn more, and stay safe. https://socialmedia.xdme.com/tony/videos-book18/page-142.mp4 https://www.youtube.com/embed/7MY2Hsw5v74 114 2026-10-04T22:32:30+00:00 yes https://xdme.com/watch-book18-q143.html https://xdme.com/book18-thumbs/page-143.jpg How Can Kids Help Scientists Count Penguins? Kids can help count penguins from anywhere in the world, with a grown-up's help! Cameras in Antarctica take thousands of pictures of penguin colonies, all year long. Online volunte https://socialmedia.xdme.com/tony/videos-book18/page-143.mp4 https://www.youtube.com/embed/WGyL4NlZEfw 119 2026-10-04T22:35:02+00:00 yes https://xdme.com/watch-book18-q144.html https://xdme.com/book18-thumbs/page-144.jpg What Jobs Do People Do in Polar Science? Polar science takes a whole team, with many different jobs, and maybe one is perfect for you! Some people study ice, some study the sea, and some study animals. Others keep everyon https://socialmedia.xdme.com/tony/videos-book18/page-144.mp4 https://www.youtube.com/embed/E26gxvPfnDg 120 2026-10-04T22:38:05+00:00 yes https://xdme.com/watch-book18-q145.html https://xdme.com/book18-thumbs/page-145.jpg Why Must Visitors Wash Their Boots Before Entering Polar Places? Visitors wash their boots to keep tiny hitchhikers out of polar places! Seeds, spores, and germs can ride along on boots and clothes. Polar nature is special, and it needs our prot https://socialmedia.xdme.com/tony/videos-book18/page-145.mp4 https://www.youtube.com/embed/Q9dnlivGEq4 114 2026-10-04T22:41:08+00:00 yes https://xdme.com/watch-book18-q146.html https://xdme.com/book18-thumbs/page-146.jpg What Can Kids Do to Take Care of Icy Places? Kids can take care of icy places with small, steady habits! You can learn, share, save energy, and care for nature near home. Every small step shows you care. https://socialmedia.xdme.com/tony/videos-book18/page-146.mp4 https://www.youtube.com/embed/pBO3HZgsp78 111 2026-10-04T22:43:50+00:00 yes https://xdme.com/watch-book18-q147.html https://xdme.com/book18-thumbs/page-147.jpg Do Other Planets Have Polar Ice Caps? Yes! Other planets have polar ice caps too! Mars has bright white caps at its north and south poles. Mars's polar caps grow and shrink with the seasons. https://socialmedia.xdme.com/tony/videos-book18/page-147.mp4 https://www.youtube.com/embed/Ph4PP--Pjh0 116 2026-10-04T22:46:34+00:00 yes https://xdme.com/watch-book18-q148.html https://xdme.com/book18-thumbs/page-148.jpg What Is a Whiteout? A whiteout is when snow, clouds, and bright light blend together so everything looks white! The ground, the sky, and the horizon all look the same. It can be very confusing and eve https://socialmedia.xdme.com/tony/videos-book18/page-148.mp4 https://www.youtube.com/embed/e_VSsMYVlpw 110 2026-10-04T22:49:07+00:00 yes https://xdme.com/watch-book18-q149.html https://xdme.com/book18-thumbs/page-149.jpg Can You Make Sea Ice at Home? Yes, you can make sea ice at home, with a grown-up's help! Stir salt into water and chill it in the freezer. Then watch how it freezes, step by step. https://socialmedia.xdme.com/tony/videos-book18/page-149.mp4 https://www.youtube.com/embed/PVg27oBWrjo 113 2026-10-04T22:51:43+00:00 yes https://xdme.com/watch-book18-q150.html https://xdme.com/book18-thumbs/page-150.jpg What Polar Mysteries Are Still Waiting to Be Solved? Many polar mysteries are still hidden, and maybe you will solve one! The poles are huge, cold, and hard to reach. So there is a lot left to discover, and new tools make it easier e https://socialmedia.xdme.com/tony/videos-book18/page-150.mp4 https://www.youtube.com/embed/6cEktFurzS0 115 2026-10-04T22:54:18+00:00 yes https://xdme.com/watch-book19-q001.html https://xdme.com/book19-thumbs/page-001.jpg Where Does a River Begin? Most rivers begin as tiny trickles, so small you could step right across them! Rain and melting snow soak into the ground, then seep back out at a spring or run downhill. The place https://socialmedia.xdme.com/tony/videos-book19/page-001.mp4 https://www.youtube.com/embed/ELGL05Va1ko 116 2026-10-04T23:14:41+00:00 yes https://xdme.com/watch-book19-q002.html https://xdme.com/book19-thumbs/page-002.jpg What Is a Tributary? A tributary is a smaller stream or river that flows into a bigger one! Think of a tree: little twigs join into branches, and branches join into the trunk. Rivers work the same way, https://socialmedia.xdme.com/tony/videos-book19/page-002.mp4 https://www.youtube.com/embed/PVonOULcoDI 112 2026-10-04T23:14:43+00:00 yes https://xdme.com/watch-book19-q003.html https://xdme.com/book19-thumbs/page-003.jpg What Is the Mouth of a River? The mouth of a river is the place where the river ends! It flows into something bigger, like a lake or the ocean. The mouth is the opposite end of the river from its source. https://socialmedia.xdme.com/tony/videos-book19/page-003.mp4 https://www.youtube.com/embed/PYNegKlJCH8 110 2026-10-04T23:14:44+00:00 yes https://xdme.com/watch-book19-q004.html https://xdme.com/book19-thumbs/page-004.jpg How Does a River Get Bigger as It Travels? A river grows as it goes, because more water keeps joining it! Tributaries pour in, rain runs off the land, and underground water seeps into the channel. Each addition makes the ri https://socialmedia.xdme.com/tony/videos-book19/page-004.mp4 https://www.youtube.com/embed/C98X2OxsTQA 120 2026-10-04T23:14:46+00:00 yes https://xdme.com/watch-book19-q005.html https://xdme.com/book19-thumbs/page-005.jpg Why Do Mountain Streams Look So Fast and Big Rivers Look So Slow? Mountain streams look fast because they tumble down steep slopes over rocks! Big rivers flow across gentle land, so their surface looks smooth and calm. But looks can fool you. https://socialmedia.xdme.com/tony/videos-book19/page-005.mp4 https://www.youtube.com/embed/UhLsOnJ46oI 118 2026-10-04T23:14:49+00:00 yes https://xdme.com/watch-book19-q006.html https://xdme.com/book19-thumbs/page-006.jpg Which Rivers Are the Longest in the World? The longest rivers in the world stretch for thousands of miles! The Nile in Africa and the Amazon in South America are usually named the two longest, each about 4,000 miles. Scient https://socialmedia.xdme.com/tony/videos-book19/page-006.mp4 https://www.youtube.com/embed/zl59yAm8cU8 118 2026-10-04T23:15:59+00:00 yes https://xdme.com/watch-book19-q007.html https://xdme.com/book19-thumbs/page-007.jpg Are Brooks, Creeks, and Rivers Different Things? Brooks, creeks, and rivers are all moving water, but there is no perfect rule for the names! In general, brooks and creeks are small streams you might hop across. Rivers are larger https://socialmedia.xdme.com/tony/videos-book19/page-007.mp4 https://www.youtube.com/embed/ECK1bQF8908 110 2026-10-04T23:16:51+00:00 yes https://xdme.com/watch-book19-q008.html https://xdme.com/book19-thumbs/page-008.jpg Why Are River Valleys Shaped Like a V in the Mountains but Wide Near the Sea? High in the hills, a river valley looks like the letter V! Near the sea it is wide and flat. The shape depends on whether the river is cutting down or swinging sideways. https://socialmedia.xdme.com/tony/videos-book19/page-008.mp4 https://www.youtube.com/embed/BTrLLyL-U7c 115 2026-10-04T23:18:54+00:00 yes https://xdme.com/watch-book19-q009.html https://xdme.com/book19-thumbs/page-009.jpg How Does a River Carry Rocks and Sand Downstream? A river moves material in three different ways! Tiny bits float, sand hops along the bottom, and big stones roll or slide. Together, they make rivers great at shaping the land, and https://socialmedia.xdme.com/tony/videos-book19/page-009.mp4 https://www.youtube.com/embed/b2a8wzfjdD4 111 2026-10-04T23:21:28+00:00 yes https://xdme.com/watch-book19-q010.html https://xdme.com/book19-thumbs/page-010.jpg Why Do Rivers Drop Sand and Pebbles When They Slow Down? Moving water has energy, and fast water can carry heavy things! When a river slows down, it loses energy and can no longer hold its load. So it drops sand and pebbles. https://socialmedia.xdme.com/tony/videos-book19/page-010.mp4 https://www.youtube.com/embed/bMhTq9TBxj0 113 2026-10-04T23:24:31+00:00 yes https://xdme.com/watch-book19-q011.html https://xdme.com/book19-thumbs/page-011.jpg What Is a Watershed? A watershed is all the land that drains into one river! Every raindrop that lands inside it, on a roof, a field, or a hilltop, will eventually flow into the same stream or river. T https://socialmedia.xdme.com/tony/videos-book19/page-011.mp4 https://www.youtube.com/embed/rna0HD9D2sg 115 2026-10-04T23:27:05+00:00 yes https://xdme.com/watch-book19-q012.html https://xdme.com/book19-thumbs/page-012.jpg Where Does All the Mud Go at the End of a River? At a river's mouth, the current slows down and the mud and sand settle to the bottom! Over thousands of years, those layers pile up into new land called a delta. A delta is often s https://socialmedia.xdme.com/tony/videos-book19/page-012.mp4 https://www.youtube.com/embed/wHWotHMU9Vk 116 2026-10-04T23:29:44+00:00 yes https://xdme.com/watch-book19-q013.html https://xdme.com/book19-thumbs/page-013.jpg What Happens Where a River Meets the Sea? The place where a river meets the sea is called an estuary! Fresh river water mixes with salty seawater. The mixed water is called brackish, which means a little bit salty. https://socialmedia.xdme.com/tony/videos-book19/page-013.mp4 https://www.youtube.com/embed/JzfcBWl4_Uo 116 2026-10-04T23:32:46+00:00 yes https://xdme.com/watch-book19-q014.html https://xdme.com/book19-thumbs/page-014.jpg Why Does the Mackenzie River Run North Instead of South? Rivers flow downhill, not toward the south! If the land slopes toward the north, the river runs north. A river goes wherever the land tilts. https://socialmedia.xdme.com/tony/videos-book19/page-014.mp4 https://www.youtube.com/embed/MMcg54y6rRw 113 2026-10-04T23:35:50+00:00 yes https://xdme.com/watch-book19-q015.html https://xdme.com/book19-thumbs/page-015.jpg Why Do Some Rivers Split Into Many Weaving Channels? Some rivers split into many weaving channels, like braided hair! They are called braided rivers. It happens when a river carries lots of sand and gravel, and not enough water to pu https://socialmedia.xdme.com/tony/videos-book19/page-015.mp4 https://www.youtube.com/embed/VJCeEHdq3VI 111 2026-10-04T23:38:22+00:00 yes https://xdme.com/watch-book19-q016.html https://xdme.com/book19-thumbs/page-016.jpg Why Do People Argue About Where a River Really Starts? A river often has many streams feeding it, so it can be hard to say which one is the real start! People pick the source in different ways. The answer can depend on how you decide. https://socialmedia.xdme.com/tony/videos-book19/page-016.mp4 https://www.youtube.com/embed/ZDL14SjCpaY 111 2026-10-04T23:41:02+00:00 yes https://xdme.com/watch-book19-q017.html https://xdme.com/book19-thumbs/page-017.jpg How Old Are Rivers? Rivers can be very old, or surprisingly young! Some have flowed in about the same place for millions of years. Others were shaped much more recently. https://socialmedia.xdme.com/tony/videos-book19/page-017.mp4 https://www.youtube.com/embed/8kSgKgzC6lw 114 2026-10-04T23:44:06+00:00 yes https://xdme.com/watch-book19-q018.html https://xdme.com/book19-thumbs/page-018.jpg Why Does a River Sometimes Leave an Old Loop Behind as a Crescent-Shaped Lake? A winding river can leave an old loop behind as a crescent-shaped lake! It is called an oxbow lake. It forms when a river cuts straight across a bend. https://socialmedia.xdme.com/tony/videos-book19/page-018.mp4 https://www.youtube.com/embed/zSVPSqvgVXs 110 2026-10-04T23:46:40+00:00 yes https://xdme.com/watch-book19-q019.html https://xdme.com/book19-thumbs/page-019.jpg Why Does River Water Turn White and Wild Over Rocks? River water turns white over rocks because of millions of tiny air bubbles! Where a river drops steeply or runs over a bumpy bed, the water speeds up and tumbles. That makes rapids https://socialmedia.xdme.com/tony/videos-book19/page-019.mp4 https://www.youtube.com/embed/9QAW-xvZKXs 114 2026-10-04T23:49:12+00:00 yes https://xdme.com/watch-book19-q020.html https://xdme.com/book19-thumbs/page-020.jpg Where Does a River’s Water Come From When It Hasn’t Rained for Days? Many rivers are fed by groundwater, even when it hasn't rained for days! Groundwater soaks into the soil and rocks during rain and snowmelt. Then it slowly seeps out into streams. https://socialmedia.xdme.com/tony/videos-book19/page-020.mp4 https://www.youtube.com/embed/2f0mWJ448p4 114 2026-10-04T23:52:17+00:00 yes https://xdme.com/watch-book19-q021.html https://xdme.com/book19-thumbs/page-021.jpg Can a River Disappear Underground? Yes, a river can disappear underground! In places with limestone rock, water can dissolve the rock and form holes and caves. A stream can flow into a hole and travel through an und https://socialmedia.xdme.com/tony/videos-book19/page-021.mp4 https://www.youtube.com/embed/LiQjfsmHbq0 116 2026-10-04T23:54:48+00:00 yes https://xdme.com/watch-book19-q022.html https://xdme.com/book19-thumbs/page-022.jpg Why Do Some Rivers Have Different Names Along the Way? People often name a river in separate parts, or give it different names along the way! A name is a human idea, but the water just keeps flowing. So one river can wear several names https://socialmedia.xdme.com/tony/videos-book19/page-022.mp4 https://www.youtube.com/embed/iQXCx9neTTo 112 2026-10-04T23:57:53+00:00 yes https://xdme.com/watch-book19-q023.html https://xdme.com/book19-thumbs/page-023.jpg Why Are River Rocks So Smooth and Round? River rocks are smooth and round because they bump and rub together as the water carries them! Every bump knocks off tiny bits and rubs away sharp corners. This wearing down is cal https://socialmedia.xdme.com/tony/videos-book19/page-023.mp4 https://www.youtube.com/embed/SBwTtIOzriQ 111 2026-10-05T00:00:37+00:00 yes https://xdme.com/watch-book19-q024.html https://xdme.com/book19-thumbs/page-024.jpg Where Does River Water Go After It Reaches the Sea? River water goes back up into the sky after it reaches the sea! The Sun heats the ocean, and the water travels in a big circle called the water cycle. Today's river water could hav https://socialmedia.xdme.com/tony/videos-book19/page-024.mp4 https://www.youtube.com/embed/CtbbPf1g2FM 110 2026-10-05T00:03:10+00:00 yes https://xdme.com/watch-book19-q025.html https://xdme.com/book19-thumbs/page-025.jpg How Can You Follow a Raindrop From Your Street to the Sea? A raindrop that lands on your street takes a trip to the sea! It flows to the gutter, into a storm drain, and through pipes to a nearby creek or river. From there, it travels on to https://socialmedia.xdme.com/tony/videos-book19/page-025.mp4 https://www.youtube.com/embed/ulVu6ya22BY 105 2026-10-05T00:06:13+00:00 yes https://xdme.com/watch-book19-q026.html https://xdme.com/book19-thumbs/page-026.jpg How Can You Tell How Fast a River Is Moving? You can find out how fast a river is moving with a leaf and a clock! Drop the leaf in at one point and time how long it drifts a measured distance. Then divide the distance by the https://socialmedia.xdme.com/tony/videos-book19/page-026.mp4 https://www.youtube.com/embed/y8m3-GyH6Uc 112 2026-10-05T00:08:45+00:00 yes https://xdme.com/watch-book19-q027.html https://xdme.com/book19-thumbs/page-027.jpg Why Does Water Move Fastest in the Middle of a River? Water moves fastest in the middle of a river because there is less rubbing there! The bottom and sides rub against rocks, mud, and plants. That rubbing is called friction, and it s https://socialmedia.xdme.com/tony/videos-book19/page-027.mp4 https://www.youtube.com/embed/pV_At55ohG4 109 2026-10-05T00:11:48+00:00 yes https://xdme.com/watch-book19-q028.html https://xdme.com/book19-thumbs/page-028.jpg Why Does a River Dig Deeper on the Outside of a Bend? A river digs deeper on the outside of a bend because the water there flows faster! The faster water scrapes and wears away the bank. That makes the bank steep and the water deep. https://socialmedia.xdme.com/tony/videos-book19/page-028.mp4 https://www.youtube.com/embed/iQWG6UayQdI 112 2026-10-05T00:14:51+00:00 yes https://xdme.com/watch-book19-q029.html https://xdme.com/book19-thumbs/page-029.jpg What Are Riffles and Pools? Along many streams, shallow bumpy stretches called riffles alternate with calm deep spots called pools! Riffles are noisy and bubbly, and they are great homes for insects. Pools ar https://socialmedia.xdme.com/tony/videos-book19/page-029.mp4 https://www.youtube.com/embed/0b2rDl4YgQY 113 2026-10-05T00:17:26+00:00 yes https://xdme.com/watch-book19-q030.html https://xdme.com/book19-thumbs/page-030.jpg Why Does a River Bottom Have Ripples Like Little Sand Dunes? A river bottom has ripples, like little sand dunes, because moving water pushes sand along! Grains climb the back of a small hill and tumble down the front. So the hill slowly move https://socialmedia.xdme.com/tony/videos-book19/page-030.mp4 https://www.youtube.com/embed/Ba0LfRL_MXY 110 2026-10-05T00:20:29+00:00 yes https://xdme.com/watch-book19-q031.html https://xdme.com/book19-thumbs/page-031.jpg What Do Ripples and Smooth Patches on a River’s Surface Tell You? A river's surface is like a map of the bottom! Smooth patches and ripples are clues about what is hiding below. Experts can read them, but kids should only read rivers from a safe https://socialmedia.xdme.com/tony/videos-book19/page-031.mp4 https://www.youtube.com/embed/KT19OtCjHpM 110 2026-10-05T00:23:02+00:00 yes https://xdme.com/watch-book19-q032.html https://xdme.com/book19-thumbs/page-032.jpg What Colors Can River Water Be, and What Do They Mean? River water can be many colors, and each color is a clue! It can be brown with mud, green with algae, or clear over clean gravel. It can even be milky or tea-colored. https://socialmedia.xdme.com/tony/videos-book19/page-032.mp4 https://www.youtube.com/embed/gBLg7KNV0yM 113 2026-10-05T00:26:08+00:00 yes https://xdme.com/watch-book19-q033.html https://xdme.com/book19-thumbs/page-033.jpg Why Are Some Rivers Milky Turquoise? Some rivers are milky turquoise because glaciers grind rock into a fine powder! The powder is called rock flour. It floats in the water and scatters blue-green light. https://socialmedia.xdme.com/tony/videos-book19/page-033.mp4 https://www.youtube.com/embed/xSvduzR0OCI 115 2026-10-05T00:28:41+00:00 yes https://xdme.com/watch-book19-q034.html https://xdme.com/book19-thumbs/page-034.jpg Why Do Some Rivers Look Dark Like Tea? Some rivers look dark like tea because of natural stains from leaves and roots! The stains are called tannins. Very dark rivers are known as blackwater rivers. https://socialmedia.xdme.com/tony/videos-book19/page-034.mp4 https://www.youtube.com/embed/NRWobGt4Rz8 110 2026-10-05T00:31:15+00:00 yes https://xdme.com/watch-book19-q035.html https://xdme.com/book19-thumbs/page-035.jpg Is a River as Deep as It Looks? A river is not always as deep as it looks! Darker color and smooth surface can hint at depth, but you cannot be sure. That is why kids should stay back from the water's edge. https://socialmedia.xdme.com/tony/videos-book19/page-035.mp4 https://www.youtube.com/embed/k9zeAmro7x8 109 2026-10-05T00:33:58+00:00 yes https://xdme.com/watch-book19-q036.html https://xdme.com/book19-thumbs/page-036.jpg What Does a Stream Gauge Do? A stream gauge is a station that measures how high the water in a river is, and how fast it flows! It sends the information by satellite or radio to scientists and to the public. I https://socialmedia.xdme.com/tony/videos-book19/page-036.mp4 https://www.youtube.com/embed/nu0nnKh5Igs 110 2026-10-05T00:37:01+00:00 yes https://xdme.com/watch-book19-q037.html https://xdme.com/book19-thumbs/page-037.jpg How Do Scientists Measure How Much Water a River Carries? Scientists measure how much water a river carries by checking three things! They measure how wide the river is, how deep it is, and how fast the water moves. Then they multiply the https://socialmedia.xdme.com/tony/videos-book19/page-037.mp4 https://www.youtube.com/embed/Q0ANIihzFiY 113 2026-10-05T00:39:40+00:00 yes https://xdme.com/watch-book19-q038.html https://xdme.com/book19-thumbs/page-038.jpg Why Does River Temperature Change During the Day and Seasons? River temperature changes during the day and across the seasons! Sunlight warms the surface, and shady banks and trees help keep water cool. Water from deep springs stays cooler. https://socialmedia.xdme.com/tony/videos-book19/page-038.mp4 https://www.youtube.com/embed/paL9sief6BM 113 2026-10-05T00:42:13+00:00 yes https://xdme.com/watch-book19-q039.html https://xdme.com/book19-thumbs/page-039.jpg Why Do Some Rivers Have Foam on Top? Some rivers have foam on top, and often it is completely natural! Leaves and plants release soap-like substances into the water. When the water tumbles over rocks, it whips in air. https://socialmedia.xdme.com/tony/videos-book19/page-039.mp4 https://www.youtube.com/embed/hU1IbJ--oPI 114 2026-10-05T00:45:17+00:00 yes https://xdme.com/watch-book19-q040.html https://xdme.com/book19-thumbs/page-040.jpg What Is an Eddy? An eddy is a patch of water that swirls in a circle or flows backward! It forms behind a rock, a bend, or some other obstacle. It happens where fast water passes slow water. https://socialmedia.xdme.com/tony/videos-book19/page-040.mp4 https://www.youtube.com/embed/w7cbYdj3moM 109 2026-10-05T00:47:49+00:00 yes https://xdme.com/watch-book19-q041.html https://xdme.com/book19-thumbs/page-041.jpg Can Scientists Listen to Rocks Rolling Along a River Bed? Yes, scientists can listen to rocks rolling along a river bed! They lower microphones called hydrophones, or place sensors on the bank. The microphones pick up the clicking and cla https://socialmedia.xdme.com/tony/videos-book19/page-041.mp4 https://www.youtube.com/embed/WhbERDzAsZs 115 2026-10-05T00:50:52+00:00 yes https://xdme.com/watch-book19-q042.html https://xdme.com/book19-thumbs/page-042.jpg What Can River Pebbles Tell Us About Upstream? Each pebble in a river came from somewhere upstream! By looking at the kinds of rocks, scientists can tell which hills and mountains the river flows through. A handful of gravel is https://socialmedia.xdme.com/tony/videos-book19/page-042.mp4 https://www.youtube.com/embed/R7EWV1EeKr0 115 2026-10-05T00:54:00+00:00 yes https://xdme.com/watch-book19-q043.html https://xdme.com/book19-thumbs/page-043.jpg What Do the Layers in a Riverbank Tell Us? The layers in a riverbank are like pages in a book! A cut bank often shows stripes of sand, gravel, and mud. The river laid them down over many years. https://socialmedia.xdme.com/tony/videos-book19/page-043.mp4 https://www.youtube.com/embed/-jVG3o4EFkM 109 2026-10-05T00:56:32+00:00 yes https://xdme.com/watch-book19-q044.html https://xdme.com/book19-thumbs/page-044.jpg What Is a Sandbar, and Why Does It Move? A sandbar is a ridge of sand or gravel that builds up inside a river or near its mouth! It forms where the water slows and drops its load. And it can move when the river changes. https://socialmedia.xdme.com/tony/videos-book19/page-044.mp4 https://www.youtube.com/embed/C3-irIfxsQE 110 2026-10-05T00:59:37+00:00 yes https://xdme.com/watch-book19-q045.html https://xdme.com/book19-thumbs/page-045.jpg How Do Scientists Follow River Water with Harmless Dye? Scientists sometimes release a safe, bright dye into a stream and watch how it travels! The dye shows how fast the water moves and how it mixes. It can even show where the water go https://socialmedia.xdme.com/tony/videos-book19/page-045.mp4 https://www.youtube.com/embed/XKIC4Fj1IIM 111 2026-10-05T01:02:08+00:00 yes https://xdme.com/watch-book19-q046.html https://xdme.com/book19-thumbs/page-046.jpg How Can You Read a River on a Map? On a map, rivers appear as blue lines! Small blue lines join bigger ones, like branches on a tree. With a little practice, you can read a whole river from source to mouth. https://socialmedia.xdme.com/tony/videos-book19/page-046.mp4 https://www.youtube.com/embed/M1ugeqoioN8 107 2026-10-05T01:04:41+00:00 yes https://xdme.com/watch-book19-q047.html https://xdme.com/book19-thumbs/page-047.jpg What Is a Seam, Where Fast and Slow Currents Meet? A seam is the line where a fast current meets slow, calm water! It often shows bubbles, foam, or little swirls. It can look like a wiggly line on the water. https://socialmedia.xdme.com/tony/videos-book19/page-047.mp4 https://www.youtube.com/embed/B4u_yOxASpU 105 2026-10-05T01:07:45+00:00 yes https://xdme.com/watch-book19-q048.html https://xdme.com/book19-thumbs/page-048.jpg How Do Whirling Pebbles Drill Holes in River Rock? Whirling pebbles can drill round holes in hard river rock! The holes are called potholes. They are made by water and stones, not by tools. https://socialmedia.xdme.com/tony/videos-book19/page-048.mp4 https://www.youtube.com/embed/Un1wtpxp8yA 109 2026-10-05T01:10:48+00:00 yes https://xdme.com/watch-book19-q049.html https://xdme.com/book19-thumbs/page-049.jpg Why Does a Wave Stay in One Place While the River Rushes Through It? A river wave can stay in one place while the water rushes through it! It is called a standing wave. The water moves, but the shape stays the same. https://socialmedia.xdme.com/tony/videos-book19/page-049.mp4 https://www.youtube.com/embed/MvmgayhrqiY 112 2026-10-05T01:13:52+00:00 yes https://xdme.com/watch-book19-q050.html https://xdme.com/book19-thumbs/page-050.jpg How Do Scientists Map the Bottom of a River? Scientists map the bottom of a river with sonar! Sonar sends a pulse of sound down and times how long the echo takes to return. A boat travels back and forth to build a map. https://socialmedia.xdme.com/tony/videos-book19/page-050.mp4 https://www.youtube.com/embed/-pK6auUVQiU 108 2026-10-05T01:16:24+00:00 yes https://xdme.com/watch-book19-q051.html https://xdme.com/book19-thumbs/page-051.jpg Why Do River Fish Face Upstream? River fish usually point their noses into the current, which means they face upstream! Facing the flow helps them breathe, eat, and stay steady. It lets the river do some of the wo https://socialmedia.xdme.com/tony/videos-book19/page-051.mp4 https://www.youtube.com/embed/YBebeKI-RaU 116 2026-10-05T01:19:30+00:00 yes https://xdme.com/watch-book19-q052.html https://xdme.com/book19-thumbs/page-052.jpg How Do Fish Hold Still in Fast Water? Fish hold still in fast water by using smart body tricks and smart hiding spots! Smooth shapes, calm pockets, and strong fins all help. They let a fish stay put without getting tir https://socialmedia.xdme.com/tony/videos-book19/page-052.mp4 https://www.youtube.com/embed/5SF45OseZY4 111 2026-10-05T01:22:03+00:00 yes https://xdme.com/watch-book19-q053.html https://xdme.com/book19-thumbs/page-053.jpg What Lives Under the Rocks in a River? Under river rocks live lots of tiny animals, like mayfly nymphs, stonefly nymphs, and caddisfly larvae! They are called water bugs, and they are important helpers. A single rock ca https://socialmedia.xdme.com/tony/videos-book19/page-053.mp4 https://www.youtube.com/embed/8ek6rZnArDE 117 2026-10-05T01:25:06+00:00 yes https://xdme.com/watch-book19-q054.html https://xdme.com/book19-thumbs/page-054.jpg How Do River Insects Breathe Underwater? Many young river insects breathe underwater with gills, thin feathery parts that pull oxygen out of the water! Different insects wear their gills in different places. Clean, fast, https://socialmedia.xdme.com/tony/videos-book19/page-054.mp4 https://www.youtube.com/embed/yrKdybKh7qc 117 2026-10-05T01:28:08+00:00 yes https://xdme.com/watch-book19-q055.html https://xdme.com/book19-thumbs/page-055.jpg Why Do Mayflies Live Only a Day as Adults? Mayflies spend most of their lives underwater, then live as winged adults for only a short time! As adults, they do not eat at all. Their job is simple: find a mate and lay eggs. https://socialmedia.xdme.com/tony/videos-book19/page-055.mp4 https://www.youtube.com/embed/JvJcfXFTYRM 116 2026-10-05T01:30:41+00:00 yes https://xdme.com/watch-book19-q056.html https://xdme.com/book19-thumbs/page-056.jpg How Do River Bugs Cling to Rocks in a Strong Current? River bugs have clever grips, like flat bodies, claws, hooks, and sticky silk! These tricks keep them from being swept away. Staying low and staying put wins in fast water. https://socialmedia.xdme.com/tony/videos-book19/page-056.mp4 https://www.youtube.com/embed/-mo5ZC72OLA 113 2026-10-05T01:33:44+00:00 yes https://xdme.com/watch-book19-q057.html https://xdme.com/book19-thumbs/page-057.jpg Why Does Rushing Water Hold More Oxygen? Oxygen from the air dissolves into water at the surface, and rushing water mixes in lots more! Tumbling over rocks splashes air into the stream. That helps animals that need lots o https://socialmedia.xdme.com/tony/videos-book19/page-057.mp4 https://www.youtube.com/embed/ZdwD6iA9KKQ 115 2026-10-05T01:36:16+00:00 yes https://xdme.com/watch-book19-q058.html https://xdme.com/book19-thumbs/page-058.jpg How Do River Otters Stay Warm and Dry in the Water? River otters have two layers of fur that trap air and keep water away from their skin! That air layer works like a cozy, waterproof jacket. It keeps them warm and dry, even in cold https://socialmedia.xdme.com/tony/videos-book19/page-058.mp4 https://www.youtube.com/embed/WhnCy3Mxu4c 111 2026-10-05T01:39:19+00:00 yes https://xdme.com/watch-book19-q059.html https://xdme.com/book19-thumbs/page-059.jpg Why Do River Insects Let Go and Drift Downstream at Night? After dark, many river insects let go of the rocks and float downstream. Scientists call it drift! It is a safer time to travel. More insects drift in the first hours after sunset https://socialmedia.xdme.com/tony/videos-book19/page-059.mp4 https://www.youtube.com/embed/vMtHw_vXAsU 117 2026-10-05T01:41:51+00:00 yes https://xdme.com/watch-book19-q060.html https://xdme.com/book19-thumbs/page-060.jpg What Is a Dipper, the Bird That Walks Underwater? The American dipper is a small gray songbird that walks underwater to find food! It lives beside fast mountain streams. It is built for diving into the current. https://socialmedia.xdme.com/tony/videos-book19/page-060.mp4 https://www.youtube.com/embed/b7wluIL1yXk 109 2026-10-05T01:45:08+00:00 yes https://xdme.com/watch-book19-q061.html https://xdme.com/book19-thumbs/page-061.jpg How Does a Kingfisher Dive for a Snack? A belted kingfisher dives headfirst into the water to catch small fish! It is a champion fisher with a built-in spear. Then it flies back to a branch to enjoy its meal. https://socialmedia.xdme.com/tony/videos-book19/page-061.mp4 https://www.youtube.com/embed/VnUr4YNIuhc 112 2026-10-05T01:47:47+00:00 yes https://xdme.com/watch-book19-q062.html https://xdme.com/book19-thumbs/page-062.jpg How Do American Eels Swim From Rivers to the Faraway Sargasso Sea? American eels grow up in rivers, then swim all the way to the Sargasso Sea to have babies! The Sargasso Sea is a part of the Atlantic Ocean near Bermuda. It is one of the greatest https://socialmedia.xdme.com/tony/videos-book19/page-062.mp4 https://www.youtube.com/embed/LvfUZHuChQE 114 2026-10-05T01:50:20+00:00 yes https://xdme.com/watch-book19-q063.html https://xdme.com/book19-thumbs/page-063.jpg Why Do Salmon Swim Up Rivers? Many salmon hatch in a river, swim out to the ocean to grow, and then return to the river where they were born! They go home to lay their eggs. Then the next generation begins. https://socialmedia.xdme.com/tony/videos-book19/page-063.mp4 https://www.youtube.com/embed/iaotl-WGiGc 109 2026-10-05T01:52:53+00:00 yes https://xdme.com/watch-book19-q064.html https://xdme.com/book19-thumbs/page-064.jpg How Do Young Fish Grow Up in a River? Young fish grow up in safe nests and shelters, then slowly move to bigger water as they get strong! They hide, nibble tiny bugs, and grow. Calm spots and plants keep them safe, and https://socialmedia.xdme.com/tony/videos-book19/page-064.mp4 https://www.youtube.com/embed/5AcN0pRdwOM 113 2026-10-05T01:55:57+00:00 yes https://xdme.com/watch-book19-q065.html https://xdme.com/book19-thumbs/page-065.jpg Why Do Fish Leap Out of Rivers? Fish jump out of rivers for lots of different reasons! Some are hunting, some are escaping, and some are traveling. And sometimes scientists are not sure why a fish jumped, so the https://socialmedia.xdme.com/tony/videos-book19/page-065.mp4 https://www.youtube.com/embed/HVrra_ngW3o 108 2026-10-05T01:58:29+00:00 yes https://xdme.com/watch-book19-q066.html https://xdme.com/book19-thumbs/page-066.jpg Can Dolphins Live in Fresh Water? Yes! A few kinds of river dolphins live in big rivers in Asia and South America! They are real dolphins that live in fresh water. River dolphins have flexible necks that help them https://socialmedia.xdme.com/tony/videos-book19/page-066.mp4 https://www.youtube.com/embed/95KqBsR58yM 113 2026-10-05T02:01:32+00:00 yes https://xdme.com/watch-book19-q067.html https://xdme.com/book19-thumbs/page-067.jpg Why Do Frogs and Tadpoles Live in Quiet Corners of a River? Frog eggs and tadpoles are soft and small, so they would be swept away in fast water! That is why they stay in calm corners. Quiet places keep them safe while they grow, so many mo https://socialmedia.xdme.com/tony/videos-book19/page-067.mp4 https://www.youtube.com/embed/DVTx38g2i4s 114 2026-10-05T02:04:03+00:00 yes https://xdme.com/watch-book19-q068.html https://xdme.com/book19-thumbs/page-068.jpg How Can River Plants Bend Without Breaking? River plants bend without breaking because they are flexible, and the water helps hold them up! They sway with the current instead of fighting it. Soft and bendy wins in a river. https://socialmedia.xdme.com/tony/videos-book19/page-068.mp4 https://www.youtube.com/embed/LTH-h-zsWDA 110 2026-10-05T02:07:06+00:00 yes https://xdme.com/watch-book19-q069.html https://xdme.com/book19-thumbs/page-069.jpg How Do Trees Along a Riverbank Help the Animals in the Water? Trees along a riverbank are green helpers that take care of the animals in the water! They give shade, food, and shelter to fish, insects, frogs, and birds. Their roots even keep t https://socialmedia.xdme.com/tony/videos-book19/page-069.mp4 https://www.youtube.com/embed/WkHSzsV5CKU 117 2026-10-05T02:10:10+00:00 yes https://xdme.com/watch-book19-q070.html https://xdme.com/book19-thumbs/page-070.jpg How Does a River Feed the Animals Along Its Banks? A river is like a food highway that feeds animals along its banks! Fish, insects, and plants bring in hungry visitors. Everything is connected, in a big web of life. https://socialmedia.xdme.com/tony/videos-book19/page-070.mp4 https://www.youtube.com/embed/u0PtBNp0Y-E 112 2026-10-05T02:12:42+00:00 yes https://xdme.com/watch-book19-q071.html https://xdme.com/book19-thumbs/page-071.jpg Why Are Fallen Trees Good for a River? A tree that falls into a river becomes a home for lots of animals! It makes shelter and food, and it changes the flow of the water. Fallen wood is good for rivers. https://socialmedia.xdme.com/tony/videos-book19/page-071.mp4 https://www.youtube.com/embed/9pdEvakUUak 114 2026-10-05T02:15:16+00:00 yes https://xdme.com/watch-book19-q072.html https://xdme.com/book19-thumbs/page-072.jpg Which Animals Wake Up Along a River at Night? When the Sun sets, a whole new crew wakes up along the river! Bats, owls, raccoons, muskrats, and frogs all get busy, and fireflies may blink too. A river at night is full of sound https://socialmedia.xdme.com/tony/videos-book19/page-072.mp4 https://www.youtube.com/embed/aBkCsqT043Y 114 2026-10-05T02:18:18+00:00 yes https://xdme.com/watch-book19-q073.html https://xdme.com/book19-thumbs/page-073.jpg What Are Freshwater Mussels Doing on the Riverbed? Freshwater mussels sit half buried in the sand, pulling in water and filtering out tiny bits of food! They work like living water filters, cleaning the river as they feed. That hel https://socialmedia.xdme.com/tony/videos-book19/page-073.mp4 https://www.youtube.com/embed/eaSN-Km9Qw4 116 2026-10-05T02:21:22+00:00 yes https://xdme.com/watch-book19-q074.html https://xdme.com/book19-thumbs/page-074.jpg Why Do Sturgeon Look Like Dinosaurs? Sturgeon look like dinosaurs because they are very ancient fish that have changed little for millions of years! They have bony plates instead of scales. They really are called livi https://socialmedia.xdme.com/tony/videos-book19/page-074.mp4 https://www.youtube.com/embed/C_gmwzzDhXE 116 2026-10-05T02:28:15+00:00 yes https://xdme.com/watch-book19-q075.html https://xdme.com/book19-thumbs/page-075.jpg How Do Animals Cross a Rushing River? Animals cross rivers in many clever ways, but they choose their crossing spots carefully! Some swim, some fly, and some float, and some even team up. Kids should never try to cross https://socialmedia.xdme.com/tony/videos-book19/page-075.mp4 https://www.youtube.com/embed/OwsCiOJ6nWY 117 2026-10-05T02:32:34+00:00 yes https://xdme.com/watch-book19-q076.html https://xdme.com/book19-thumbs/page-076.jpg Why Did People Build Towns Next to Rivers? People built towns next to rivers because rivers give so much! They supply water, food, rich soil, and a way to travel. That is why many big cities sit beside rivers. https://socialmedia.xdme.com/tony/videos-book19/page-076.mp4 https://www.youtube.com/embed/RCPn2gS5gMo 114 2026-10-04T23:16:12+00:00 yes https://xdme.com/watch-book19-q077.html https://xdme.com/book19-thumbs/page-077.jpg How Did Rivers Become Highways? Before roads and railways, rivers were the highways, and travelers floated or paddled along them! Boats could carry heavy loads easily, which made rivers the best roads. Rivers con https://socialmedia.xdme.com/tony/videos-book19/page-077.mp4 https://www.youtube.com/embed/6rgHHIwTxrI 122 2026-10-04T23:16:13+00:00 yes https://xdme.com/watch-book19-q078.html https://xdme.com/book19-thumbs/page-078.jpg Why Were Birchbark Canoes So Clever? Indigenous peoples of northern North America built light, strong canoes from birch bark, cedar wood, and spruce roots! They sealed them with spruce gum. The design came from genera https://socialmedia.xdme.com/tony/videos-book19/page-078.mp4 https://www.youtube.com/embed/t3yE-bdaCRY 119 2026-10-04T23:16:15+00:00 yes https://xdme.com/watch-book19-q079.html https://xdme.com/book19-thumbs/page-079.jpg How Does a Paddle Move a Canoe Forward? When you pull a paddle backward through the water, the canoe moves forward! You push the water, and the water pushes back. That is a famous science idea, and it works for rockets, https://socialmedia.xdme.com/tony/videos-book19/page-079.mp4 https://www.youtube.com/embed/vSyiHlCuWTk 115 2026-10-04T23:16:16+00:00 yes https://xdme.com/watch-book19-q080.html https://xdme.com/book19-thumbs/page-080.jpg Why Do Flat-Bottomed Boats Work Well in Shallow Rivers? A flat-bottomed boat sits high in the water, so it needs less depth to float! That is perfect for shallow rivers. Boats like scows and punts are built this way, and some are pushed https://socialmedia.xdme.com/tony/videos-book19/page-080.mp4 https://www.youtube.com/embed/i6ZPe4QTrxQ 114 2026-10-04T23:16:18+00:00 yes https://xdme.com/watch-book19-q081.html https://xdme.com/book19-thumbs/page-081.jpg How Can a Ferry Cross a River Without an Engine? Some river ferries have no engine at all. The river itself pushes them across! They are called reaction ferries or cable ferries. Reaction ferries are powered by the river itself. https://socialmedia.xdme.com/tony/videos-book19/page-081.mp4 https://www.youtube.com/embed/oVmfZTvIYhw 113 2026-10-04T23:16:19+00:00 yes https://xdme.com/watch-book19-q082.html https://xdme.com/book19-thumbs/page-082.jpg What Is a Ford, and Why Were Fords Important? A ford is a shallow, firm place where people could cross a river on foot or by cart! Long ago, there were few bridges. So fords were very important crossing points, and roads led t https://socialmedia.xdme.com/tony/videos-book19/page-082.mp4 https://www.youtube.com/embed/Kb0KoDZI7dw 112 2026-10-04T23:16:52+00:00 yes https://xdme.com/watch-book19-q083.html https://xdme.com/book19-thumbs/page-083.jpg How Does a Canal Lock Lift a Boat Uphill? A canal lock lifts a boat uphill using only water and gravity! It is a chamber with gates at both ends. No pumps are needed, only gravity and patience. https://socialmedia.xdme.com/tony/videos-book19/page-083.mp4 https://www.youtube.com/embed/tdi-O_AozvE 114 2026-10-04T23:18:56+00:00 yes https://xdme.com/watch-book19-q084.html https://xdme.com/book19-thumbs/page-084.jpg How Is a Canal Different From a River? A river is a natural channel that formed on its own, but a canal is dug by people! A canal is made for boats. Canals use the same water but work very differently from rivers. https://socialmedia.xdme.com/tony/videos-book19/page-084.mp4 https://www.youtube.com/embed/wJehAsi2Ghs 115 2026-10-04T23:21:29+00:00 yes https://xdme.com/watch-book19-q085.html https://xdme.com/book19-thumbs/page-085.jpg How Did Boats Travel Upstream Before Engines? Before engines, boaters traveled upstream with paddles, poles, sails, and ropes! It was slow and took lots of muscle, and a trip upstream could take weeks. Some even used horses to https://socialmedia.xdme.com/tony/videos-book19/page-085.mp4 https://www.youtube.com/embed/lkElyqiO6p4 113 2026-10-04T23:24:33+00:00 yes https://xdme.com/watch-book19-q086.html https://xdme.com/book19-thumbs/page-086.jpg How Did Paddlewheel Steamboats Work? A paddlewheel steamboat used hot steam to turn a giant wheel that pushed the boat along! It burned wood or coal to make steam. The wheel did the pushing, with a splashing, chugging https://socialmedia.xdme.com/tony/videos-book19/page-086.mp4 https://www.youtube.com/embed/314t74ZGTUw 111 2026-10-04T23:27:10+00:00 yes https://xdme.com/watch-book19-q087.html https://xdme.com/book19-thumbs/page-087.jpg How Can a Barge Carry So Much? Barges are wide, flat boats that can carry a huge load because water holds them up! A tug boat pushes them along. One barge can carry as much as many trucks. https://socialmedia.xdme.com/tony/videos-book19/page-087.mp4 https://www.youtube.com/embed/NCat8O2vDso 107 2026-10-04T23:29:45+00:00 yes https://xdme.com/watch-book19-q088.html https://xdme.com/book19-thumbs/page-088.jpg How Do River Pilots Avoid Hidden Sandbars? River pilots avoid hidden sandbars with charts, markers, sound waves, and plenty of experience! A river keeps changing, so pilots need clues, because sand moves in the current. The https://socialmedia.xdme.com/tony/videos-book19/page-088.mp4 https://www.youtube.com/embed/yJHzcgckvLE 118 2026-10-04T23:32:47+00:00 yes https://xdme.com/watch-book19-q089.html https://xdme.com/book19-thumbs/page-089.jpg How Does a Water Wheel Turn? Flowing water pushes against paddles or buckets on a big wheel and makes it turn! The turning wheel can do useful work, like grinding grain or sawing wood. People have used water w https://socialmedia.xdme.com/tony/videos-book19/page-089.mp4 https://www.youtube.com/embed/TT_D47Mroy4 111 2026-10-04T23:35:19+00:00 yes https://xdme.com/watch-book19-q090.html https://xdme.com/book19-thumbs/page-090.jpg How Did a Water Mill Grind Grain Into Flour? A water mill used the turning of a water wheel to spin heavy millstones that crushed grain into flour! The river did the hard work, so people did not need to grind by hand. Then ba https://socialmedia.xdme.com/tony/videos-book19/page-090.mp4 https://www.youtube.com/embed/C1EIe_OtGXI 113 2026-10-04T23:38:31+00:00 yes https://xdme.com/watch-book19-q091.html https://xdme.com/book19-thumbs/page-091.jpg How Does a Hydroelectric Dam Make Electricity? A hydroelectric dam turns the power of falling water into electricity! Water flows through big pipes and spins a turbine. It is clean power that burns no fuel, and it can keep runn https://socialmedia.xdme.com/tony/videos-book19/page-091.mp4 https://www.youtube.com/embed/EL5XZebltT0 119 2026-10-04T23:41:04+00:00 yes https://xdme.com/watch-book19-q092.html https://xdme.com/book19-thumbs/page-092.jpg What Are the Gates and Spillway on a Dam For? A spillway and gates let a dam release extra water safely! That keeps the dam safe and the river steady. Water released from a dam can rise suddenly. https://socialmedia.xdme.com/tony/videos-book19/page-092.mp4 https://www.youtube.com/embed/Dotcu5EHIgM 110 2026-10-04T23:44:08+00:00 yes https://xdme.com/watch-book19-q093.html https://xdme.com/book19-thumbs/page-093.jpg How Do Fish Get Past a Dam? Fish get past a dam using a fish ladder, which works like a staircase of water! Many fish must swim upstream to lay their eggs. A dam can block their way, so people built a helping https://socialmedia.xdme.com/tony/videos-book19/page-093.mp4 https://www.youtube.com/embed/C2dTJwnf4Uc 107 2026-10-04T23:46:41+00:00 yes https://xdme.com/watch-book19-q094.html https://xdme.com/book19-thumbs/page-094.jpg How Did Loggers Float Trees Down Rivers? Long ago, workers floated trees down rivers in a big event called a log drive! Spring floods carried the logs to sawmills. It was hard work done by skilled people, who also cooked https://socialmedia.xdme.com/tony/videos-book19/page-094.mp4 https://www.youtube.com/embed/szifqp1nEOo 117 2026-10-04T23:49:14+00:00 yes https://xdme.com/watch-book19-q095.html https://xdme.com/book19-thumbs/page-095.jpg How Does a Life Jacket Keep You Afloat? A life jacket keeps you afloat because it is filled with foam or air chambers that are lighter than water! It pushes up on your body. That force is called buoyancy. https://socialmedia.xdme.com/tony/videos-book19/page-095.mp4 https://www.youtube.com/embed/LFTYePp7KGo 109 2026-10-04T23:51:46+00:00 yes https://xdme.com/watch-book19-q096.html https://xdme.com/book19-thumbs/page-096.jpg How Can Ocean-Going Ships Sail Deep Inside a Continent? Ocean-going ships can sail deep inside a continent using a system called the St. Lawrence Seaway! It is made of locks, canals, and channels. https://socialmedia.xdme.com/tony/videos-book19/page-096.mp4 https://www.youtube.com/embed/DMZH65o4tRU 118 2026-10-04T23:54:50+00:00 yes https://xdme.com/watch-book19-q097.html https://xdme.com/book19-thumbs/page-097.jpg What Is a River Port? A river port is a place where ships and barges load and unload cargo on a river! It is like a bus station, but for boats. Goods arrive and leave every day, in all kinds of weather. https://socialmedia.xdme.com/tony/videos-book19/page-097.mp4 https://www.youtube.com/embed/k4WxfYLWDYc 110 2026-10-04T23:57:54+00:00 yes https://xdme.com/watch-book19-q098.html https://xdme.com/book19-thumbs/page-098.jpg How Did Early Explorers Map Rivers? Early explorers mapped rivers by sketching as they traveled and using simple tools! They also learned from people who already knew the rivers. Together, they drew maps for others t https://socialmedia.xdme.com/tony/videos-book19/page-098.mp4 https://www.youtube.com/embed/iJcQLEEMaYU 118 2026-10-05T00:01:08+00:00 yes https://xdme.com/watch-book19-q099.html https://xdme.com/book19-thumbs/page-099.jpg What Is a Weir? A weir is a low wall built across a river to raise the water level a little or to measure the flow! Water spills over the top. It is a small, simple dam. https://socialmedia.xdme.com/tony/videos-book19/page-099.mp4 https://www.youtube.com/embed/Q5RTcayoCUQ 109 2026-10-05T00:03:41+00:00 yes https://xdme.com/watch-book19-q100.html https://xdme.com/book19-thumbs/page-100.jpg Why Are Many River Towns Built Above the Water, Not Right at the Edge? Many river towns are built above the water because rivers rise in spring and after storms! Higher ground stays dry, even when the river rises. Early settlers learned this lesson fr https://socialmedia.xdme.com/tony/videos-book19/page-100.mp4 https://www.youtube.com/embed/W_q0f01W9Bo 116 2026-10-05T00:06:14+00:00 yes https://xdme.com/watch-book19-q101.html https://xdme.com/book19-thumbs/page-101.jpg Why Do Rivers Rise Every Spring? Rivers rise every spring because winter snow melts all at once! In cold places, snow piles up on the land and in the mountains all winter long. When spring warmth arrives, the melt https://socialmedia.xdme.com/tony/videos-book19/page-101.mp4 https://www.youtube.com/embed/PA_tgYRZbxk 116 2026-10-05T00:09:17+00:00 yes https://xdme.com/watch-book19-q102.html https://xdme.com/book19-thumbs/page-102.jpg Why Can a River Be High on a Sunny Day? A river can be high on a sunny day because the rain fell far away! A storm in the mountains sends water downstream, and it takes time to travel. So the sky can be blue where you ar https://socialmedia.xdme.com/tony/videos-book19/page-102.mp4 https://www.youtube.com/embed/ul39TsZ2tfg 117 2026-10-05T00:11:50+00:00 yes https://xdme.com/watch-book19-q103.html https://xdme.com/book19-thumbs/page-103.jpg How Do Forecasters Know a River Is About to Flood? Forecasters know a river is about to flood by measuring rain, snow, and river height! They gather lots of clues and put them together in a computer. Then they send warnings so peop https://socialmedia.xdme.com/tony/videos-book19/page-103.mp4 https://www.youtube.com/embed/WKI-9XmYnXE 106 2026-10-05T00:14:55+00:00 yes https://xdme.com/watch-book19-q104.html https://xdme.com/book19-thumbs/page-104.jpg What Does “Flood Stage” Mean? Flood stage is the water level where a river starts to cause trouble! At that height, water begins to spill over the banks onto roads or near buildings. It gives everyone an easy w https://socialmedia.xdme.com/tony/videos-book19/page-104.mp4 https://www.youtube.com/embed/xL3GTTGT0GI 113 2026-10-05T00:17:28+00:00 yes https://xdme.com/watch-book19-q105.html https://xdme.com/book19-thumbs/page-105.jpg Why Is the Land Near a River So Rich for Farming? Land near a river is rich for farming because floods leave fresh soil behind! The flat land beside a river is called the floodplain. Every flood spreads a thin layer of fine mud an https://socialmedia.xdme.com/tony/videos-book19/page-105.mp4 https://www.youtube.com/embed/Eir2yXIjHU8 110 2026-10-05T00:20:30+00:00 yes https://xdme.com/watch-book19-q106.html https://xdme.com/book19-thumbs/page-106.jpg What Is a Levee? A levee is a long raised bank or wall built beside a river to hold the water in! Levees help protect farms and towns during high water. But they can only hold so much, so people mu https://socialmedia.xdme.com/tony/videos-book19/page-106.mp4 https://www.youtube.com/embed/6HQfPuBijAs 109 2026-10-05T00:23:03+00:00 yes https://xdme.com/watch-book19-q107.html https://xdme.com/book19-thumbs/page-107.jpg Why Is Floodwater Stronger than It Looks? Floodwater is stronger than it looks because moving water is very heavy! Even a small amount of fast water has a lot of pushing power. The safest choice is always to stay far away https://socialmedia.xdme.com/tony/videos-book19/page-107.mp4 https://www.youtube.com/embed/KshufOYsMF0 110 2026-10-05T00:26:09+00:00 yes https://xdme.com/watch-book19-q108.html https://xdme.com/book19-thumbs/page-108.jpg Why Does Rain Run Off Pavement Faster than It Soaks Into Grass? Rain runs off pavement faster than it soaks into grass because pavement cannot soak up water! Soil is full of tiny spaces that act like a sponge. Pavement and roofs have no spaces, https://socialmedia.xdme.com/tony/videos-book19/page-108.mp4 https://www.youtube.com/embed/RaqpbZS8wC0 110 2026-10-05T00:28:42+00:00 yes https://xdme.com/watch-book19-q109.html https://xdme.com/book19-thumbs/page-109.jpg How Do Forests and Wetlands Slow Down a Rising River? Forests and wetlands slow down a rising river because they work like sponges! They soak up rain and slow the water as it moves. That keeps the flood lower and spreads the flow over https://socialmedia.xdme.com/tony/videos-book19/page-109.mp4 https://www.youtube.com/embed/U7065KFTwfo 111 2026-10-05T00:31:56+00:00 yes https://xdme.com/watch-book19-q110.html https://xdme.com/book19-thumbs/page-110.jpg Why Do Rivers Get Smaller in Late Summer? Rivers get smaller in late summer because the water coming in drops way down! The snow is gone, the soil is dry, and there has been less rain. So the river shrinks and shows more o https://socialmedia.xdme.com/tony/videos-book19/page-110.mp4 https://www.youtube.com/embed/xzDUr-pnYVI 113 2026-10-05T00:34:30+00:00 yes https://xdme.com/watch-book19-q111.html https://xdme.com/book19-thumbs/page-111.jpg What Happens to River Animals When the Water Gets Low? When river water gets low, animals find cooler, deeper spots to wait it out! Fish, insects, and frogs each have their own tricks. Then fall rains come back and the river fills up a https://socialmedia.xdme.com/tony/videos-book19/page-111.mp4 https://www.youtube.com/embed/3ZLuWhixePA 109 2026-10-05T00:37:09+00:00 yes https://xdme.com/watch-book19-q112.html https://xdme.com/book19-thumbs/page-112.jpg How Can You See a Drought in a River? You can see a drought in a river because the water gets low and rocks poke out! A drought is a long time with much less rain and snow than normal. The river gets shallow, and clues https://socialmedia.xdme.com/tony/videos-book19/page-112.mp4 https://www.youtube.com/embed/vOpIZKwW1XE 107 2026-10-05T00:39:41+00:00 yes https://xdme.com/watch-book19-q113.html https://xdme.com/book19-thumbs/page-113.jpg What Can a Dry Riverbed Tell Us? A dry riverbed tells us where water once flowed! Even without water, the shape of the land holds clues about the river. Scientists read those clues to learn about the past. https://socialmedia.xdme.com/tony/videos-book19/page-113.mp4 https://www.youtube.com/embed/w3zdxl3nlfs 111 2026-10-05T00:42:46+00:00 yes https://xdme.com/watch-book19-q114.html https://xdme.com/book19-thumbs/page-114.jpg Why Do Rivers Freeze Later than Ponds and Lakes? Rivers freeze later than ponds and lakes because moving water is hard to freeze! Flowing, churning water keeps mixing and breaks up any ice trying to form. Still water lets ice spr https://socialmedia.xdme.com/tony/videos-book19/page-114.mp4 https://www.youtube.com/embed/cO_m2CSrNAg 111 2026-10-05T00:45:18+00:00 yes https://xdme.com/watch-book19-q115.html https://xdme.com/book19-thumbs/page-115.jpg Why Does Ice Grow Out From the Riverbank First? Ice grows out from the riverbank first because the edges are slow, shallow, and cold! The fast, deep middle keeps flowing, so it stays open longer. Thin shelves of ice reach out fr https://socialmedia.xdme.com/tony/videos-book19/page-115.mp4 https://www.youtube.com/embed/OZPxXyOzDzU 109 2026-10-05T00:47:50+00:00 yes https://xdme.com/watch-book19-q116.html https://xdme.com/book19-thumbs/page-116.jpg What Is Frazil Ice? Frazil ice is a river slush made of tiny ice crystals! On very cold nights, rushing water can cool slightly below freezing. Then crystals form all through the flow, like a slushy d https://socialmedia.xdme.com/tony/videos-book19/page-116.mp4 https://www.youtube.com/embed/wdO9aajja9I 113 2026-10-05T00:50:53+00:00 yes https://xdme.com/watch-book19-q117.html https://xdme.com/book19-thumbs/page-117.jpg Can Ice Grow on the Bottom of a River? Yes, ice can grow on the bottom of a river! It is called anchor ice. On cold, clear nights, tiny ice crystals can stick to rocks and plants on the riverbed. https://socialmedia.xdme.com/tony/videos-book19/page-117.mp4 https://www.youtube.com/embed/XsjSFwEtxmk 109 2026-10-05T00:53:24+00:00 yes https://xdme.com/watch-book19-q118.html https://xdme.com/book19-thumbs/page-118.jpg Why Does River Ice Boom and Groan? River ice booms and groans because it is stretching and squeezing! Ice shrinks when it gets colder and expands when it warms. The banks hold it in place, so stress builds up until https://socialmedia.xdme.com/tony/videos-book19/page-118.mp4 https://www.youtube.com/embed/Gb683xNFQP8 107 2026-10-05T00:56:33+00:00 yes https://xdme.com/watch-book19-q119.html https://xdme.com/book19-thumbs/page-119.jpg How Can Ice Pile Up and Block a River in Spring? Ice can pile up and block a river in spring when broken ice gets stuck! The pile acts like a dam made of ice. Water backs up behind it and can spill over the banks. https://socialmedia.xdme.com/tony/videos-book19/page-119.mp4 https://www.youtube.com/embed/0tSYsISLkJs 106 2026-10-05T00:59:05+00:00 yes https://xdme.com/watch-book19-q120.html https://xdme.com/book19-thumbs/page-120.jpg What Is Spring Breakup on a Northern River? Spring breakup is when the ice on a northern river breaks apart and moves! It is the end of the frozen winter and the start of open water. Northern towns watch for it very closely. https://socialmedia.xdme.com/tony/videos-book19/page-120.mp4 https://www.youtube.com/embed/9WEObkfCl64 108 2026-10-05T01:02:10+00:00 yes https://xdme.com/watch-book19-q121.html https://xdme.com/book19-thumbs/page-121.jpg Why Is River Ice Never Safe to Walk On? River ice is never safe to walk on because it can be thin without any warning! Moving water wears the ice away from underneath. So thick-looking ice can still be weak. https://socialmedia.xdme.com/tony/videos-book19/page-121.mp4 https://www.youtube.com/embed/j54clLo6HH0 108 2026-10-05T01:05:13+00:00 yes https://xdme.com/watch-book19-q122.html https://xdme.com/book19-thumbs/page-122.jpg How Do Fish Survive Under River Ice? Fish survive under river ice because the water below stays liquid! The ice on top acts like a lid that keeps the water underneath from freezing solid. Fish slow down and rest in de https://socialmedia.xdme.com/tony/videos-book19/page-122.mp4 https://www.youtube.com/embed/p5P8qngrVYA 113 2026-10-05T01:07:47+00:00 yes https://xdme.com/watch-book19-q123.html https://xdme.com/book19-thumbs/page-123.jpg Can the Ocean Push a River Backward? Yes, the ocean can push a river backward, near the coast! When the tide comes in, the sea pushes up into the river mouth. In some places, that makes the river run backward for a wh https://socialmedia.xdme.com/tony/videos-book19/page-123.mp4 https://www.youtube.com/embed/nu07FuU1ecE 110 2026-10-05T01:10:50+00:00 yes https://xdme.com/watch-book19-q124.html https://xdme.com/book19-thumbs/page-124.jpg What Does a Flood Leave Behind? After a flood, the river leaves behind mud, sand, logs, and sometimes a new channel! When the water goes down, you can see the story of what happened. Some of what it leaves behind https://socialmedia.xdme.com/tony/videos-book19/page-124.mp4 https://www.youtube.com/embed/kbkboS5vXAA 110 2026-10-05T01:13:21+00:00 yes https://xdme.com/watch-book19-q125.html https://xdme.com/book19-thumbs/page-125.jpg How Can Scientists Tell How Big a Flood Was Long Ago? Scientists can tell how big a flood was long ago by reading clues in nature! Floods leave marks on trees, cliffs, and the land. By putting the clues together, they can figure out h https://socialmedia.xdme.com/tony/videos-book19/page-125.mp4 https://www.youtube.com/embed/-Z6KJmVKFAQ 109 2026-10-05T01:16:25+00:00 yes https://xdme.com/watch-book19-q126.html https://xdme.com/book19-thumbs/page-126.jpg What Makes a River Healthy? A healthy river has clean, cool water and lots of life! Its banks have plants and trees, and its bed has gravel and rocks. It rises and falls with the seasons in a natural way. https://socialmedia.xdme.com/tony/videos-book19/page-126.mp4 https://www.youtube.com/embed/lZfiGx7YwUM 109 2026-10-05T01:19:32+00:00 yes https://xdme.com/watch-book19-q127.html https://xdme.com/book19-thumbs/page-127.jpg Why Does a Clean River Have Lots of Different Bugs? A clean river has lots of different bugs because many river bugs need clean water! Some can only live in cool water with lots of oxygen. So the bugs you find tell you about the wat https://socialmedia.xdme.com/tony/videos-book19/page-127.mp4 https://www.youtube.com/embed/Y77Ji9sgcc0 113 2026-10-05T01:22:34+00:00 yes https://xdme.com/watch-book19-q128.html https://xdme.com/book19-thumbs/page-128.jpg How Do Scientists Tell How Cloudy a River Is? Scientists tell how cloudy a river is by measuring how much light gets through! Cloudy water is called turbid, and the cloudiness is called turbidity. It comes from tiny bits float https://socialmedia.xdme.com/tony/videos-book19/page-128.mp4 https://www.youtube.com/embed/UaPzZRj1ueU 111 2026-10-05T01:25:07+00:00 yes https://xdme.com/watch-book19-q129.html https://xdme.com/book19-thumbs/page-129.jpg Why Does a River Need Oxygen? A river needs oxygen because fish, insects, and other river animals breathe it! The oxygen is dissolved in the water, mixed in invisibly. Without enough oxygen, river animals canno https://socialmedia.xdme.com/tony/videos-book19/page-129.mp4 https://www.youtube.com/embed/ZkeNHMjiV2c 118 2026-10-05T01:28:09+00:00 yes https://xdme.com/watch-book19-q130.html https://xdme.com/book19-thumbs/page-130.jpg What Does a Water Test Kit Check? A water test kit checks how healthy water is, using simple tests! It can measure pH, nutrients, and temperature, all in just a few minutes. Test strips change color to show the num https://socialmedia.xdme.com/tony/videos-book19/page-130.mp4 https://www.youtube.com/embed/quOi-PciU34 118 2026-10-05T01:30:42+00:00 yes https://xdme.com/watch-book19-q131.html https://xdme.com/book19-thumbs/page-131.jpg What Makes Green Slime Grow in a River? Green slime grows in a river when algae get warm sunshine and extra nutrients! Algae are tiny plant-like living things that live in water. Too many nutrients make them grow fast. https://socialmedia.xdme.com/tony/videos-book19/page-131.mp4 https://www.youtube.com/embed/hEAsrGaG8dY 116 2026-10-05T01:33:45+00:00 yes https://xdme.com/watch-book19-q132.html https://xdme.com/book19-thumbs/page-132.jpg How Do Detectives Find Where Pollution Is Entering a River? Detectives find where pollution enters a river by testing the water at many spots! They compare clean water upstream with water farther downstream. The change shows where the troub https://socialmedia.xdme.com/tony/videos-book19/page-132.mp4 https://www.youtube.com/embed/CmO3B4YnbHQ 117 2026-10-05T01:36:48+00:00 yes https://xdme.com/watch-book19-q133.html https://xdme.com/book19-thumbs/page-133.jpg How Does Litter Travel Down a River? A river carries whatever falls into it, and that includes litter! Bottles, bags, and cans float or roll along with the current. They can end up stuck on a bank or far away in the s https://socialmedia.xdme.com/tony/videos-book19/page-133.mp4 https://www.youtube.com/embed/cnCY4_WuqZc 113 2026-10-05T01:39:20+00:00 yes https://xdme.com/watch-book19-q134.html https://xdme.com/book19-thumbs/page-134.jpg How Can a Water Wheel with Googly Eyes Clean a River? Mr. Trash Wheel is a floating machine with big googly eyes that cleans a river! It lives in Baltimore in the United States. Mr. Trash Wheel has other trash-wheel friends with names https://socialmedia.xdme.com/tony/videos-book19/page-134.mp4 https://www.youtube.com/embed/XTq9Im6o3XE 109 2026-10-05T01:41:53+00:00 yes https://xdme.com/watch-book19-q135.html https://xdme.com/book19-thumbs/page-135.jpg How Can a Strip of Plants Catch Muddy Runoff Before It Reaches the River? A strip of plants along a river catches muddy runoff before it reaches the water! It is called a buffer, and it works like nature's filter. It keeps the river cleaner and healthier https://socialmedia.xdme.com/tony/videos-book19/page-135.mp4 https://www.youtube.com/embed/6WsLz7q4V0w 111 2026-10-05T01:45:09+00:00 yes https://xdme.com/watch-book19-q136.html https://xdme.com/book19-thumbs/page-136.jpg How Do Scientists Bring the Wiggles Back to a Straightened River? Scientists bring the wiggles back to a straightened river by rebuilding its natural bends! A straight channel is a poor home for fish and bugs. A wiggly river has more places to li https://socialmedia.xdme.com/tony/videos-book19/page-136.mp4 https://www.youtube.com/embed/YmFJksyfdeA 112 2026-10-05T01:47:48+00:00 yes https://xdme.com/watch-book19-q137.html https://xdme.com/book19-thumbs/page-137.jpg How Do Scientists Count Fish They Can’t See? Scientists count fish they can't see with gentle tools like cameras, sound, and tiny tags! The goal is to learn how many fish live in a river. That helps them see if the fish are d https://socialmedia.xdme.com/tony/videos-book19/page-137.mp4 https://www.youtube.com/embed/YX-aTDEekGw 110 2026-10-05T01:50:22+00:00 yes https://xdme.com/watch-book19-q138.html https://xdme.com/book19-thumbs/page-138.jpg How Can a Cup of River Water Tell Who Lives There? A cup of river water can tell who lives there because animals leave tiny traces of themselves! These traces are called eDNA, short for environmental DNA. Scientists read them like https://socialmedia.xdme.com/tony/videos-book19/page-138.mp4 https://www.youtube.com/embed/Qrx20cGsKgA 112 2026-10-05T01:52:55+00:00 yes https://xdme.com/watch-book19-q139.html https://xdme.com/book19-thumbs/page-139.jpg How Do Satellites and Drones Watch a Whole River at Once? Satellites and drones watch a whole river at once by taking pictures from above! Satellites see the big picture from far above in space. Drones fly lower to see the details. https://socialmedia.xdme.com/tony/videos-book19/page-139.mp4 https://www.youtube.com/embed/g_Qqocsi1LU 110 2026-10-05T01:55:26+00:00 yes https://xdme.com/watch-book19-q140.html https://xdme.com/book19-thumbs/page-140.jpg How Do Sensors Keep Watch on a River Day and Night? Sensors keep watch on a river day and night by measuring it all the time! They never get tired or need to sleep, and they work in all kinds of weather. They send the numbers to sci https://socialmedia.xdme.com/tony/videos-book19/page-140.mp4 https://www.youtube.com/embed/SKcbBoFPj2w 111 2026-10-05T01:58:30+00:00 yes https://xdme.com/watch-book19-q141.html https://xdme.com/book19-thumbs/page-141.jpg How Do Floating Trackers Show Where River Water Goes? Floating trackers show where river water goes by drifting along with it! They carry GPS, which sends their location to a screen. Scientists can follow their path in real time, as i https://socialmedia.xdme.com/tony/videos-book19/page-141.mp4 https://www.youtube.com/embed/h0Ia9gHk2tU 108 2026-10-05T02:01:01+00:00 yes https://xdme.com/watch-book19-q142.html https://xdme.com/book19-thumbs/page-142.jpg How Can Kids Help Look After a River? Kids can help look after a river in lots of safe ways! Small jobs on land protect the water downstream. Every helper makes a difference, no matter how small. https://socialmedia.xdme.com/tony/videos-book19/page-142.mp4 https://www.youtube.com/embed/ka-p5OkVuyM 113 2026-10-05T02:04:05+00:00 yes https://xdme.com/watch-book19-q143.html https://xdme.com/book19-thumbs/page-143.jpg What Jobs Do People Do with Rivers? Many people work with rivers, and each job is different! Some measure water, some study animals, and some design big machines. There is a river job for every kind of curious kid, w https://socialmedia.xdme.com/tony/videos-book19/page-143.mp4 https://www.youtube.com/embed/l78Xeg2UxEE 117 2026-10-05T02:07:08+00:00 yes https://xdme.com/watch-book19-q144.html https://xdme.com/book19-thumbs/page-144.jpg How Can Old Maps Show That a River Has Moved? Old maps can show that a river has moved by comparing where it used to flow! Rivers change their paths over decades. Laying old maps over new ones reveals the change. https://socialmedia.xdme.com/tony/videos-book19/page-144.mp4 https://www.youtube.com/embed/TDT7T5QOtys 111 2026-10-05T02:09:39+00:00 yes https://xdme.com/watch-book19-q145.html https://xdme.com/book19-thumbs/page-145.jpg What Is a Rain Garden? A rain garden is a shallow, planted dip in the ground that collects rain! Instead of rushing into a storm drain, the water soaks in slowly. It keeps streams cleaner, and it helps b https://socialmedia.xdme.com/tony/videos-book19/page-145.mp4 https://www.youtube.com/embed/g8atqlmrUdw 114 2026-10-05T02:12:43+00:00 yes https://xdme.com/watch-book19-q146.html https://xdme.com/book19-thumbs/page-146.jpg How Do Experienced Boaters Decide Whether a River Is Safe to Paddle? Experienced boaters decide a river is safe to paddle by checking lots of things first! They check before they ever touch the water, and they never paddle alone. If anything looks r https://socialmedia.xdme.com/tony/videos-book19/page-146.mp4 https://www.youtube.com/embed/FC441Azn45c 113 2026-10-05T02:15:17+00:00 yes https://xdme.com/watch-book19-q147.html https://xdme.com/book19-thumbs/page-147.jpg How Does a River Help Clean Itself? A river helps clean itself with built-in helpers! Sunlight, rapids, tiny microbes, bugs, mussels, and plants all pitch in. But a river can only clean so much, so it needs our help https://socialmedia.xdme.com/tony/videos-book19/page-147.mp4 https://www.youtube.com/embed/7jPHM3xuNH4 117 2026-10-05T02:18:20+00:00 yes https://xdme.com/watch-book19-q148.html https://xdme.com/book19-thumbs/page-148.jpg Are There Rivers on Other Worlds? Yes, there are rivers on other worlds, and some used to flow with water! Long ago, Mars had rivers, and scientists are exploring the clues. And on a moon of Saturn, rivers flow rig https://socialmedia.xdme.com/tony/videos-book19/page-148.mp4 https://www.youtube.com/embed/tgSxf4uvJrI 113 2026-10-05T02:21:24+00:00 yes https://xdme.com/watch-book19-q149.html https://xdme.com/book19-thumbs/page-149.jpg How Can You Safely Explore a River? You can safely explore a river by watching from a safe spot with a grown-up! Looking, listening, and drawing are all great ways to learn about the river. You do not need to touch t https://socialmedia.xdme.com/tony/videos-book19/page-149.mp4 https://www.youtube.com/embed/hDo9UjSJaEg 113 2026-10-05T02:28:17+00:00 yes https://xdme.com/watch-book19-q150.html https://xdme.com/book19-thumbs/page-150.jpg Which River Secrets Can Nobody Explain Yet? Rivers still hold many secrets that nobody can explain yet! Scientists are still asking big questions about how rivers work, and some answers may take years. The next great discove https://socialmedia.xdme.com/tony/videos-book19/page-150.mp4 https://www.youtube.com/embed/BXfjMWVnB78 113 2026-10-05T02:32:37+00:00 yes https://xdme.com/watch-book20-q001.html https://xdme.com/book20-thumbs/page-001.jpg How Tall Does a Hill Have to Be to Become a Mountain? There is no perfect rule for how tall a hill must be to become a mountain! Many maps call land a mountain when it rises about 1,000 feet, or 300 meters, above the land around it. L https://socialmedia.xdme.com/tony/videos-book20/page-001.mp4 https://www.youtube.com/embed/JXq3xyuMUf0 112 2026-10-05T03:08:39+00:00 yes https://xdme.com/watch-book20-q002.html https://xdme.com/book20-thumbs/page-002.jpg What Are the Biggest Mountain Ranges in the World? A mountain range is a long row of mountains, like a giant fence across the land! The Himalayas hold the highest peaks on Earth, and the Andes are the longest range on land. Five fa https://socialmedia.xdme.com/tony/videos-book20/page-002.mp4 https://www.youtube.com/embed/2e_A_3_8Kow 124 2026-10-05T03:08:41+00:00 yes https://xdme.com/watch-book20-q003.html https://xdme.com/book20-thumbs/page-003.jpg Which Is the Tallest Mountain on Each Continent? Every continent has its own tallest mountain, and some are really different from each other! Mount Everest in Asia is the tallest in the world at about 29,000 feet. Let's visit all https://socialmedia.xdme.com/tony/videos-book20/page-003.mp4 https://www.youtube.com/embed/vRAtmFPKeLY 128 2026-10-05T03:08:42+00:00 yes https://xdme.com/watch-book20-q004.html https://xdme.com/book20-thumbs/page-004.jpg Is Mount Everest Really the Tallest Mountain? It depends on how you measure! Mount Everest has the highest peak above sea level, but two other mountains win in different ways. Mauna Kea is tallest from base to top, and Chimbor https://socialmedia.xdme.com/tony/videos-book20/page-004.mp4 https://www.youtube.com/embed/ZpokRR68iBs 120 2026-10-05T03:08:44+00:00 yes https://xdme.com/watch-book20-q005.html https://xdme.com/book20-thumbs/page-005.jpg How Do Surveyors Measure the Height of a Mountain? Surveyors are people who measure land very carefully, even the height of giant mountains! For many years, they measured angles to the peak from two known spots, then used geometry https://socialmedia.xdme.com/tony/videos-book20/page-005.mp4 https://www.youtube.com/embed/H0cfdFF-4yY 122 2026-10-05T03:08:45+00:00 yes https://xdme.com/watch-book20-q006.html https://xdme.com/book20-thumbs/page-006.jpg What Are the Main Kinds of Mountains? Mountains form in different ways, so there are different kinds of mountains! Four main kinds are fold mountains, fault-block mountains, volcanic mountains, and dome mountains. Wind https://socialmedia.xdme.com/tony/videos-book20/page-006.mp4 https://www.youtube.com/embed/OiY5zKeDOZA 121 2026-10-05T03:08:46+00:00 yes https://xdme.com/watch-book20-q007.html https://xdme.com/book20-thumbs/page-007.jpg Why Are the Rocky Mountains Jagged but the Appalachians Rounded? Age makes the difference! The Rockies are young mountains with steep sides and sharp peaks, while the Appalachians are much older and have been worn down to rounded hills. Over tim https://socialmedia.xdme.com/tony/videos-book20/page-007.mp4 https://www.youtube.com/embed/Bguk-qO9CEA 117 2026-10-05T03:08:48+00:00 yes https://xdme.com/watch-book20-q008.html https://xdme.com/book20-thumbs/page-008.jpg What Makes the Canadian Rockies So Special? The Canadian Rockies in Alberta and British Columbia have towering peaks, turquoise lakes, glaciers, and forests, all in one place! They are so special that big areas are protected https://socialmedia.xdme.com/tony/videos-book20/page-008.mp4 https://www.youtube.com/embed/s_GPmJT_Gqg 125 2026-10-05T03:08:49+00:00 yes https://xdme.com/watch-book20-q009.html https://xdme.com/book20-thumbs/page-009.jpg What Is the Tallest Mountain in Canada? The tallest mountain in Canada is Mount Logan! It rises 19,551 feet, or 5,959 meters, in Yukon, in the northwest part of the country. That also makes it the second highest mountain https://socialmedia.xdme.com/tony/videos-book20/page-009.mp4 https://www.youtube.com/embed/7M9S6tCAOLc 121 2026-10-05T03:08:50+00:00 yes https://xdme.com/watch-book20-q010.html https://xdme.com/book20-thumbs/page-010.jpg What Makes the Andes the Longest Mountain Range on Land? The Andes run down the western edge of South America for about 4,300 miles! That is the longest mountain range on land, and it passes through seven countries. https://socialmedia.xdme.com/tony/videos-book20/page-010.mp4 https://www.youtube.com/embed/ad0GZlsVnbg 120 2026-10-05T03:08:58+00:00 yes https://xdme.com/watch-book20-q011.html https://xdme.com/book20-thumbs/page-011.jpg Why Is There Snow on a Mountain Near the Equator? Mount Kilimanjaro in Tanzania sits close to the equator, where the land is hot, yet it still has snow on top! The secret is height. Its summit is almost 20,000 feet up, where the a https://socialmedia.xdme.com/tony/videos-book20/page-011.mp4 https://www.youtube.com/embed/URYK8KHzmOw 115 2026-10-05T03:09:00+00:00 yes https://xdme.com/watch-book20-q012.html https://xdme.com/book20-thumbs/page-012.jpg Are There Mountains Under the Sea? Yes! The sea floor has huge mountains, and some are taller than mountains on land. They are called seamounts, and there are tens of thousands of them. https://socialmedia.xdme.com/tony/videos-book20/page-012.mp4 https://www.youtube.com/embed/1dpSMlOXyX4 117 2026-10-05T03:09:01+00:00 yes https://xdme.com/watch-book20-q013.html https://xdme.com/book20-thumbs/page-013.jpg Which Is the Tallest Mountain in the Whole Solar System? The tallest known mountain in our solar system is Olympus Mons on Mars! It is a giant volcano about 13.6 miles, or 22 kilometers, high. https://socialmedia.xdme.com/tony/videos-book20/page-013.mp4 https://www.youtube.com/embed/NY3rFsN2h-s 117 2026-10-05T03:09:10+00:00 yes https://xdme.com/watch-book20-q014.html https://xdme.com/book20-thumbs/page-014.jpg Why Do Some Mountains Have Flat Tops? Some mountains have flat tops because a hard layer of rock protects the softer rock below it! As rain and wind wear away the land around it, the hard cap stays in place. That leave https://socialmedia.xdme.com/tony/videos-book20/page-014.mp4 https://www.youtube.com/embed/nos6-SoyWqk 113 2026-10-05T03:11:31+00:00 yes https://xdme.com/watch-book20-q015.html https://xdme.com/book20-thumbs/page-015.jpg How Did the Matterhorn Get Its Pointed Shape? The Matterhorn in the Alps is a classic horn peak, and glaciers made its pointed shape! Long ago, ice formed on every side of the mountain and carved out bowl-shaped hollows. The r https://socialmedia.xdme.com/tony/videos-book20/page-015.mp4 https://www.youtube.com/embed/K83qWSjr-f0 120 2026-10-05T03:14:19+00:00 yes https://xdme.com/watch-book20-q016.html https://xdme.com/book20-thumbs/page-016.jpg What Is a Mountain Pass? A mountain pass is a low spot between two peaks, like a gap in a wall! Roads, rails, and trails use passes to cross the mountains. That is easier than climbing over the top. https://socialmedia.xdme.com/tony/videos-book20/page-016.mp4 https://www.youtube.com/embed/93gPoWvVTGU 111 2026-10-05T03:16:50+00:00 yes https://xdme.com/watch-book20-q017.html https://xdme.com/book20-thumbs/page-017.jpg How Does a Glacier Turn a Mountain Valley Into a U? A river carves a valley shaped like a V, but a glacier turns it into a U! A glacier is thick and heavy, and it flows like a slow bulldozer. https://socialmedia.xdme.com/tony/videos-book20/page-017.mp4 https://www.youtube.com/embed/9UaIFoJphEw 114 2026-10-05T03:19:53+00:00 yes https://xdme.com/watch-book20-q018.html https://xdme.com/book20-thumbs/page-018.jpg How Do Mountains Get Their Names? Mountains get their names in lots of ways! Many are named for what they look like, for explorers and scientists, or for older local names. Every name has a little story. https://socialmedia.xdme.com/tony/videos-book20/page-018.mp4 https://www.youtube.com/embed/TYaSu-fdIzc 113 2026-10-05T03:22:30+00:00 yes https://xdme.com/watch-book20-q019.html https://xdme.com/book20-thumbs/page-019.jpg Do Mountains Have Roots? Yes, in a way, mountains have roots! Earth's crust floats on the softer rock below it, like an iceberg in water. Tall mountains have deep roots of crust pushing down underneath the https://socialmedia.xdme.com/tony/videos-book20/page-019.mp4 https://www.youtube.com/embed/tNnihWDZlyc 114 2026-10-05T03:25:03+00:00 yes https://xdme.com/watch-book20-q020.html https://xdme.com/book20-thumbs/page-020.jpg Why Do Faraway Mountains Look Blue? Faraway mountains look blue because the air between you and them is never perfectly clear! Tiny bits in the air scatter blue light more than red light. Lots of scattered blue light https://socialmedia.xdme.com/tony/videos-book20/page-020.mp4 https://www.youtube.com/embed/L7Zgxd_yjlw 113 2026-10-05T03:28:06+00:00 yes https://xdme.com/watch-book20-q021.html https://xdme.com/book20-thumbs/page-021.jpg What Is the Continental Divide? The Continental Divide is a line along mountain ridges where rain and melting snow choose different directions! Water on one side flows toward one ocean, and water on the other sid https://socialmedia.xdme.com/tony/videos-book20/page-021.mp4 https://www.youtube.com/embed/JT5YohFErZ4 116 2026-10-05T03:31:19+00:00 yes https://xdme.com/watch-book20-q022.html https://xdme.com/book20-thumbs/page-022.jpg What Do Mountain Words Like Peak, Ridge, and Saddle Mean? Mountain words help people describe places exactly! A peak is the high point, a ridge is a long line of high ground, and a saddle is a dip between two peaks. Let's learn a few more https://socialmedia.xdme.com/tony/videos-book20/page-022.mp4 https://www.youtube.com/embed/SvDcJ4IrpqQ 111 2026-10-05T03:33:51+00:00 yes https://xdme.com/watch-book20-q023.html https://xdme.com/book20-thumbs/page-023.jpg How Steep Is a Steep Mountain Slope? Slopes are measured in degrees or in percent grade! A gentle walking path may rise only a few degrees, while a very steep slope can be much more. Cliffs can be close to vertical. https://socialmedia.xdme.com/tony/videos-book20/page-023.mp4 https://www.youtube.com/embed/c4BGh-AP1C0 109 2026-10-05T03:36:36+00:00 yes https://xdme.com/watch-book20-q024.html https://xdme.com/book20-thumbs/page-024.jpg Can a Mountain Wear Away to Nothing? Yes, a mountain can wear away, but it takes millions of years! Rain, ice, wind, and rivers slowly break rock into pieces and carry it away. This wearing away is called erosion. https://socialmedia.xdme.com/tony/videos-book20/page-024.mp4 https://www.youtube.com/embed/ZU-ZPL4N0iA 114 2026-10-05T03:39:46+00:00 yes https://xdme.com/watch-book20-q025.html https://xdme.com/book20-thumbs/page-025.jpg How Do Scientists Figure Out How Old a Mountain Is? Scientists use clocks hidden in rocks to find out how old a mountain is! Certain minerals contain atoms that slowly change over time. Measuring those changes reveals when a rock fo https://socialmedia.xdme.com/tony/videos-book20/page-025.mp4 https://www.youtube.com/embed/IHqa5xJwQT0 117 2026-10-05T03:42:49+00:00 yes https://xdme.com/watch-book20-q026.html https://xdme.com/book20-thumbs/page-026.jpg Why Does It Get Colder as You Go Up a Mountain? It gets colder as you go up a mountain because the air higher up is thinner and cooler! On average, air cools about 3.5 degrees Fahrenheit for every 1,000 feet you climb. https://socialmedia.xdme.com/tony/videos-book20/page-026.mp4 https://www.youtube.com/embed/_gmVp4_Fv-o 111 2026-10-05T03:45:56+00:00 yes https://xdme.com/watch-book20-q027.html https://xdme.com/book20-thumbs/page-027.jpg What Are Life Zones on a Mountain? Life zones are bands, like stripes, where different plants and animals live as you go up a mountain! Each stripe has its own temperature, wind, and soil. So each one is a different https://socialmedia.xdme.com/tony/videos-book20/page-027.mp4 https://www.youtube.com/embed/F8hphc_K4v0 114 2026-10-05T03:48:33+00:00 yes https://xdme.com/watch-book20-q028.html https://xdme.com/book20-thumbs/page-028.jpg What Is the Treeline? The treeline is the height above which trees cannot grow! Below it is forest, and above it are small plants and rock. Why do the trees stop? https://socialmedia.xdme.com/tony/videos-book20/page-028.mp4 https://www.youtube.com/embed/MKhUCaMnOIo 108 2026-10-05T03:51:13+00:00 yes https://xdme.com/watch-book20-q029.html https://xdme.com/book20-thumbs/page-029.jpg Why Do Trees Get Short and Twisted Near the Top? Near the treeline, icy winds and blowing ice crystals scour off buds and branches on the windy side! Trees survive by staying low and growing sideways. They can look like flags, wi https://socialmedia.xdme.com/tony/videos-book20/page-029.mp4 https://www.youtube.com/embed/DTc3TYSfFWI 113 2026-10-05T03:54:17+00:00 yes https://xdme.com/watch-book20-q030.html https://xdme.com/book20-thumbs/page-030.jpg Why Does Climbing a Mountain Feel Like Traveling Toward the Poles? Climbing a mountain can feel like traveling toward the poles! As you go up, the temperature drops, just like when you travel north. Plants and animals change in a similar way. https://socialmedia.xdme.com/tony/videos-book20/page-030.mp4 https://www.youtube.com/embed/gQIrRGF5MDs 110 2026-10-05T03:57:07+00:00 yes https://xdme.com/watch-book20-q031.html https://xdme.com/book20-thumbs/page-031.jpg What Lives in the Foothills? Foothills are the low, rolling hills at the base of mountains, and lots of animals live there! They are warmer and drier than the zones higher up. Let's meet the neighbors. https://socialmedia.xdme.com/tony/videos-book20/page-031.mp4 https://www.youtube.com/embed/MrTZombQgRs 112 2026-10-05T04:00:29+00:00 yes https://xdme.com/watch-book20-q032.html https://xdme.com/book20-thumbs/page-032.jpg What Is a Montane Forest? Montane means of the mountains! A montane forest is the zone where trees grow tall and thick, usually evergreens like fir, pine, and spruce. It has cooler summers and more snow tha https://socialmedia.xdme.com/tony/videos-book20/page-032.mp4 https://www.youtube.com/embed/JNihjKIc-rE 118 2026-10-05T04:05:47+00:00 yes https://xdme.com/watch-book20-q033.html https://xdme.com/book20-thumbs/page-033.jpg Why Are Mountain Evergreen Trees Shaped Like Cones? Mountain evergreens are shaped like cones because the shape helps them handle heavy snow! Pine, spruce, and fir trees often have a narrow cone shape. https://socialmedia.xdme.com/tony/videos-book20/page-033.mp4 https://www.youtube.com/embed/VfDbHBGaY9g 115 2026-10-05T04:09:20+00:00 yes https://xdme.com/watch-book20-q034.html https://xdme.com/book20-thumbs/page-034.jpg Why Is One Side of a Mountain Greener than the Other? One side of a mountain can be greener than the other because of the sun! Slopes that face the sun get more warmth, while slopes that face away stay cooler and damper. Each side has https://socialmedia.xdme.com/tony/videos-book20/page-034.mp4 https://www.youtube.com/embed/8MlQV3Qcn2s 113 2026-10-05T04:13:01+00:00 yes https://xdme.com/watch-book20-q035.html https://xdme.com/book20-thumbs/page-035.jpg Why Do Mountain Meadows Burst Into Flowers All at Once? Mountain meadows burst into flowers all at once because the summer is so short! When the snow melts, plants race to bloom, make seeds, and store food before cold weather returns. F https://socialmedia.xdme.com/tony/videos-book20/page-035.mp4 https://www.youtube.com/embed/CrcsVrMGEYc 115 2026-10-05T04:16:35+00:00 yes https://xdme.com/watch-book20-q036.html https://xdme.com/book20-thumbs/page-036.jpg What Is the Alpine Zone? The alpine zone is the land above the treeline! It is windy, cold, and bright. Only tough, tiny plants and a few animals can live there. https://socialmedia.xdme.com/tony/videos-book20/page-036.mp4 https://www.youtube.com/embed/-9swj7GaIrw 112 2026-10-05T04:17:09+00:00 yes https://xdme.com/watch-book20-q037.html https://xdme.com/book20-thumbs/page-037.jpg Why Does Some Mountain Snow Turn Pink? Some mountain snow turns pink because of tiny living things called algae! In late spring and summer, they wake up in the melting snow. They have a red pigment that works like sunsc https://socialmedia.xdme.com/tony/videos-book20/page-037.mp4 https://www.youtube.com/embed/V71YqEOth5A 112 2026-10-05T04:17:10+00:00 yes https://xdme.com/watch-book20-q038.html https://xdme.com/book20-thumbs/page-038.jpg Why Is Mountain Soil So Thin? Mountain soil is thin because it is hard to build and easy to lose! On steep slopes, rain and melting snow wash soil downhill. And cold weather makes new soil form very slowly. https://socialmedia.xdme.com/tony/videos-book20/page-038.mp4 https://www.youtube.com/embed/cp9dV1rkNeU 113 2026-10-05T04:19:18+00:00 yes https://xdme.com/watch-book20-q039.html https://xdme.com/book20-thumbs/page-039.jpg Why Does Spring Arrive Later High on a Mountain? Spring arrives later high on a mountain because higher places stay colder for longer! Snow there takes more time to melt. So spring seems to climb the mountain, one step at a time. https://socialmedia.xdme.com/tony/videos-book20/page-039.mp4 https://www.youtube.com/embed/LrmCc4lRxik 114 2026-10-05T04:23:29+00:00 yes https://xdme.com/watch-book20-q040.html https://xdme.com/book20-thumbs/page-040.jpg What Is the Oldest Tree on a Mountain? The oldest tree on a mountain is the bristlecone pine! Bristlecone pines high in the White Mountains of California can live almost 5,000 years. That is older than any other single https://socialmedia.xdme.com/tony/videos-book20/page-040.mp4 https://www.youtube.com/embed/wmQCWnm6O6o 119 2026-10-05T04:28:05+00:00 yes https://xdme.com/watch-book20-q041.html https://xdme.com/book20-thumbs/page-041.jpg Why Do Different Animals Live at Different Heights on a Mountain? Different animals live at different heights because each one fits a certain climate! Food, shelter, and temperature decide who lives where. Let's climb the mountain in our minds an https://socialmedia.xdme.com/tony/videos-book20/page-041.mp4 https://www.youtube.com/embed/MThjLYJxqDQ 110 2026-10-05T04:31:38+00:00 yes https://xdme.com/watch-book20-q042.html https://xdme.com/book20-thumbs/page-042.jpg Do Animals Move Up and Down Mountains? Yes, many mountain animals follow the seasons up and down the slopes! This yearly up-and-down trip is called altitudinal migration. Let's follow along. https://socialmedia.xdme.com/tony/videos-book20/page-042.mp4 https://www.youtube.com/embed/y7cTVYzkhNg 114 2026-10-05T04:32:11+00:00 yes https://xdme.com/watch-book20-q043.html https://xdme.com/book20-thumbs/page-043.jpg How Can People Farm on Steep Mountain Slopes? People farm on steep mountain slopes by cutting flat steps called terraces into the hillside! Each step holds soil and water in place. That lets crops grow on land that would other https://socialmedia.xdme.com/tony/videos-book20/page-043.mp4 https://www.youtube.com/embed/Q7lGpFm43I4 113 2026-10-05T04:40:17+00:00 yes https://xdme.com/watch-book20-q044.html https://xdme.com/book20-thumbs/page-044.jpg Why Does the Sky Look Darker From a Mountaintop? The sky looks darker from a mountaintop because there is less air above you! The sky is blue because air scatters sunlight in all directions. Less air means less scattered light. https://socialmedia.xdme.com/tony/videos-book20/page-044.mp4 https://www.youtube.com/embed/UoD0Dwwld24 107 2026-10-05T04:51:20+00:00 yes https://xdme.com/watch-book20-q045.html https://xdme.com/book20-thumbs/page-045.jpg Why Can You See So Far From a Mountaintop? You can see so far from a mountaintop because Earth curves! If you stand low, the ground curves away and hides faraway things. The higher you are, the farther your view stretches. https://socialmedia.xdme.com/tony/videos-book20/page-045.mp4 https://www.youtube.com/embed/LmMJWf5PZxw 109 2026-10-05T04:51:22+00:00 yes https://xdme.com/watch-book20-q046.html https://xdme.com/book20-thumbs/page-046.jpg How Did a Famous Explorer Find Out That Plants Live in Bands on Mountains? A German scientist named Alexander von Humboldt discovered that plants live in bands on mountains! In 1802, he visited the Andes and studied the plants as he went uphill. Then he d https://socialmedia.xdme.com/tony/videos-book20/page-046.mp4 https://www.youtube.com/embed/vXwZTl3WWYQ 116 2026-10-05T04:55:34+00:00 yes https://xdme.com/watch-book20-q047.html https://xdme.com/book20-thumbs/page-047.jpg Why Is the Treeline Higher Near the Equator than in Canada? Treeline depends on temperature! Near the equator the lowlands are warm, so you must go very high to find the cold that stops trees. In Canada, the cold arrives much lower down. https://socialmedia.xdme.com/tony/videos-book20/page-047.mp4 https://www.youtube.com/embed/oCAtabM25NQ 115 2026-10-05T05:15:37+00:00 yes https://xdme.com/watch-book20-q048.html https://xdme.com/book20-thumbs/page-048.jpg What Are Sky Islands? Sky islands are mountains that rise from hot desert or grassland like islands in the sea! The cool, moist peaks hold forests and animals that cannot live in the dry lowlands. The h https://socialmedia.xdme.com/tony/videos-book20/page-048.mp4 https://www.youtube.com/embed/Q33OmHZrw7g 118 2026-10-05T05:26:10+00:00 yes https://xdme.com/watch-book20-q049.html https://xdme.com/book20-thumbs/page-049.jpg Why Are Some Mountain Plants and Animals Moving to Higher Ground? Some mountain plants and animals are moving to higher ground because the climate is getting warmer! When it warms, the cool zone shifts uphill. Some living things follow it. https://socialmedia.xdme.com/tony/videos-book20/page-049.mp4 https://www.youtube.com/embed/DfFY4hgp4Rk 114 2026-10-05T05:29:11+00:00 yes https://xdme.com/watch-book20-q050.html https://xdme.com/book20-thumbs/page-050.jpg What Colors Make Up the Layers of a Faraway Mountain? A faraway mountain looks like a layered cake of colors! Each band of color is a different habitat, a different home for plants and animals. Let's peel back the layers. https://socialmedia.xdme.com/tony/videos-book20/page-050.mp4 https://www.youtube.com/embed/8fUYPjHDSr8 113 2026-10-05T05:33:54+00:00 yes https://xdme.com/watch-book20-q051.html https://xdme.com/book20-thumbs/page-051.jpg How Do Mountain Goats Climb Steep Cliffs Without Slipping? Mountain goats don't slip because their hooves are built like perfect climbing shoes! Each hoof has a hard outer rim and a soft, rubbery pad in the middle. Add strong shoulders and https://socialmedia.xdme.com/tony/videos-book20/page-051.mp4 https://www.youtube.com/embed/b41ApnHHvSk 117 2026-10-05T05:40:26+00:00 yes https://xdme.com/watch-book20-q052.html https://xdme.com/book20-thumbs/page-052.jpg What Do a Bighorn Sheep’s Curly Horns Tell Us? A bighorn sheep's curly horns are like a tree ring record of its age! The horns grow in a spiral, and a new ring forms on them every year. So if you count the rings, you can estima https://socialmedia.xdme.com/tony/videos-book20/page-052.mp4 https://www.youtube.com/embed/s0yx8lGUaWw 110 2026-10-05T05:40:28+00:00 yes https://xdme.com/watch-book20-q053.html https://xdme.com/book20-thumbs/page-053.jpg Why Does a Pika Make a Pile of Hay? A pika makes a pile of hay because it cannot sleep through the winter! A pika is a small, round relative of rabbits that lives among rocks high on mountains. So it stores its own f https://socialmedia.xdme.com/tony/videos-book20/page-053.mp4 https://www.youtube.com/embed/51eAQ1Id5aU 115 2026-10-05T05:40:29+00:00 yes https://xdme.com/watch-book20-q054.html https://xdme.com/book20-thumbs/page-054.jpg Why Do Marmots Whistle? Marmots whistle to warn their friends when danger is near! Hoary marmots are big, furry rodents that live in the mountains of western Canada. A loud, sharp whistle can carry far ac https://socialmedia.xdme.com/tony/videos-book20/page-054.mp4 https://www.youtube.com/embed/kQUAVwxcdbo 113 2026-10-05T05:51:46+00:00 yes https://xdme.com/watch-book20-q055.html https://xdme.com/book20-thumbs/page-055.jpg How Do Snow Leopards Live in Cold Mountains? Snow leopards live in cold mountains thanks to a built-in winter outfit! They have thick fur, wide furry paws, and a long tail. Snow leopards live high in the mountains of Central https://socialmedia.xdme.com/tony/videos-book20/page-055.mp4 https://www.youtube.com/embed/NftzJriDQr4 110 2026-10-05T05:51:47+00:00 yes https://xdme.com/watch-book20-q056.html https://xdme.com/book20-thumbs/page-056.jpg How Do Animals Like Yaks and Llamas Cope with Thin Air? Yaks and llamas cope with thin air because their bodies are built for high places! Yaks live in the Himalayas, and llamas live in the Andes. Both have special features that help th https://socialmedia.xdme.com/tony/videos-book20/page-056.mp4 https://www.youtube.com/embed/nwmuvpaE8ng 109 2026-10-05T05:51:49+00:00 yes https://xdme.com/watch-book20-q057.html https://xdme.com/book20-thumbs/page-057.jpg How Do Big Birds Soar Over Mountains Without Flapping? Big birds soar over mountains by riding invisible rising air! Eagles and condors spread their wings and let the air lift them. That way they travel far without flapping much at all https://socialmedia.xdme.com/tony/videos-book20/page-057.mp4 https://www.youtube.com/embed/PlwkWNs__Ak 116 2026-10-05T05:51:52+00:00 yes https://xdme.com/watch-book20-q058.html https://xdme.com/book20-thumbs/page-058.jpg How Does a Ptarmigan Survive in a Snow Burrow? A ptarmigan survives cold nights by tucking into a snow burrow! It sounds chilly, but snow is a great blanket. A ptarmigan is a plump, grouse-like bird that lives high in the mount https://socialmedia.xdme.com/tony/videos-book20/page-058.mp4 https://www.youtube.com/embed/c4FVgeu_e_g 112 2026-10-05T05:52:02+00:00 yes https://xdme.com/watch-book20-q059.html https://xdme.com/book20-thumbs/page-059.jpg What Are Cushion Plants? Cushion plants are tiny alpine plants that grow in round, tight mounds like pillows! They look soft and cozy, and they really are cozy inside. That shape helps them survive up wher https://socialmedia.xdme.com/tony/videos-book20/page-059.mp4 https://www.youtube.com/embed/pB5G1kOO6YE 111 2026-10-05T05:55:04+00:00 yes https://xdme.com/watch-book20-q060.html https://xdme.com/book20-thumbs/page-060.jpg Why Are Alpine Flowers So Bright for Such Little Plants? Alpine flowers are bright because they need to be noticed! The plants are small, but their flowers can be big and brightly colored. Bright colors help in two different ways. https://socialmedia.xdme.com/tony/videos-book20/page-060.mp4 https://www.youtube.com/embed/qCOnNWuil7U 115 2026-10-05T05:55:06+00:00 yes https://xdme.com/watch-book20-q061.html https://xdme.com/book20-thumbs/page-061.jpg Why Do Some Alpine Grasses Grow Baby Plants Instead of Seeds? Some alpine grasses grow baby plants instead of seeds because summers up high are short and cold! Seeds need time to ripen, and sometimes there just is not enough warm weather. So https://socialmedia.xdme.com/tony/videos-book20/page-061.mp4 https://www.youtube.com/embed/mpJwSHAjM6Q 116 2026-10-05T05:55:08+00:00 yes https://xdme.com/watch-book20-q062.html https://xdme.com/book20-thumbs/page-062.jpg How Can a Flower Bloom Through Snow? A flower can bloom through snow because it gets a head start under the snow! Some alpine plants store food in underground bulbs all year long. That way they are ready the moment sp https://socialmedia.xdme.com/tony/videos-book20/page-062.mp4 https://www.youtube.com/embed/6hSkhMRbllM 111 2026-10-05T05:55:11+00:00 yes https://xdme.com/watch-book20-q063.html https://xdme.com/book20-thumbs/page-063.jpg How Do Bumblebees Stay Warm High in the Mountains? Bumblebees stay warm high in the mountains with fuzzy coats and shivering muscles! Bumblebees are big, fuzzy bees with thick hair that holds in heat. They are great pollinators in https://socialmedia.xdme.com/tony/videos-book20/page-063.mp4 https://www.youtube.com/embed/kZLs2uVfzEY 118 2026-10-05T05:55:13+00:00 yes https://xdme.com/watch-book20-q064.html https://xdme.com/book20-thumbs/page-064.jpg How Do Mountain Animals Find Food When Snow Covers Everything? When snow covers everything, each mountain animal has its own food plan! Some store food, some sleep, and some dig. Others simply move to lower places. https://socialmedia.xdme.com/tony/videos-book20/page-064.mp4 https://www.youtube.com/embed/MvUOwDjxoIY 112 2026-10-05T05:58:42+00:00 yes https://xdme.com/watch-book20-q065.html https://xdme.com/book20-thumbs/page-065.jpg How Can Bar-Headed Geese Fly Over the Himalayas? Bar-headed geese fly over the Himalayas, the highest mountains on Earth, with big lungs and super blood! They travel between India and Central Asia. It is one of the most amazing f https://socialmedia.xdme.com/tony/videos-book20/page-065.mp4 https://www.youtube.com/embed/oiWDic0rw0Q 114 2026-10-05T05:58:43+00:00 yes https://xdme.com/watch-book20-q066.html https://xdme.com/book20-thumbs/page-066.jpg Why Do Mountain Gorillas Have Such Thick Fur? Mountain gorillas have thick fur because their misty mountain homes are chilly and damp! They live in forests on volcanic mountains in central Africa. Their fur is like a built-in https://socialmedia.xdme.com/tony/videos-book20/page-066.mp4 https://www.youtube.com/embed/Of3OeqejYNA 115 2026-10-05T05:58:44+00:00 yes https://xdme.com/watch-book20-q067.html https://xdme.com/book20-thumbs/page-067.jpg What Is the Highest-Living Animal on Earth? The highest-living animal on Earth is a tiny jumping spider! It has been found at about 22,000 feet on Mount Everest, higher than any other known animal that lives there all year. https://socialmedia.xdme.com/tony/videos-book20/page-067.mp4 https://www.youtube.com/embed/5uHUN2tyLi8 114 2026-10-05T06:01:46+00:00 yes https://xdme.com/watch-book20-q068.html https://xdme.com/book20-thumbs/page-068.jpg Which Mountain Animals Have Built-In Snowshoes? Snowshoe hares, lynx, and ptarmigan all have built-in snowshoes! Large, furry feet spread their weight out over the snow. So they do not sink down like other animals. https://socialmedia.xdme.com/tony/videos-book20/page-068.mp4 https://www.youtube.com/embed/fcKN6Y6J84M 115 2026-10-05T06:01:48+00:00 yes https://xdme.com/watch-book20-q069.html https://xdme.com/book20-thumbs/page-069.jpg How Do Baby Mountain Goats Learn to Climb So Early? Baby mountain goats learn to climb early because they have to! Their home is a steep, rocky place where there are no flat nurseries. So they are born ready to move. https://socialmedia.xdme.com/tony/videos-book20/page-069.mp4 https://www.youtube.com/embed/4wMK1ehSxzc 112 2026-10-05T06:01:50+00:00 yes https://xdme.com/watch-book20-q070.html https://xdme.com/book20-thumbs/page-070.jpg Why Would an Ibex Climb a Dam Wall? An ibex climbs a dam wall to lick a salty snack! In Italy, a video showed Alpine ibex walking up a nearly vertical dam. The reason is hidden in the stones. https://socialmedia.xdme.com/tony/videos-book20/page-070.mp4 https://www.youtube.com/embed/IfBK_MmykY0 114 2026-10-05T06:01:52+00:00 yes https://xdme.com/watch-book20-q071.html https://xdme.com/book20-thumbs/page-071.jpg How Do Scientists Count Animals on Steep, Snowy Slopes? Scientists count animals on steep, snowy slopes using clever tools from far away! Climbing close to wild animals can be risky for people and can scare the animals. So scientists fi https://socialmedia.xdme.com/tony/videos-book20/page-071.mp4 https://www.youtube.com/embed/v6WHan4ea5Q 121 2026-10-05T06:01:53+00:00 yes https://xdme.com/watch-book20-q072.html https://xdme.com/book20-thumbs/page-072.jpg Why Do Flies Matter So Much to High-Mountain Flowers? Flies matter so much to high-mountain flowers because they are the main visitors! At high altitudes, there are fewer bees, but there are plenty of flies. So flies do much of the po https://socialmedia.xdme.com/tony/videos-book20/page-072.mp4 https://www.youtube.com/embed/Up-qQvQn2fE 117 2026-10-05T06:01:54+00:00 yes https://xdme.com/watch-book20-q073.html https://xdme.com/book20-thumbs/page-073.jpg Which Animals Live in the Canadian Rockies? The Canadian Rockies are home to lots of amazing wild animals! Each animal lives in the zone that suits it best. Some like forests, some like meadows, and some like high rocky slop https://socialmedia.xdme.com/tony/videos-book20/page-073.mp4 https://www.youtube.com/embed/gD_3qks5_sQ 115 2026-10-05T06:02:41+00:00 yes https://xdme.com/watch-book20-q074.html https://xdme.com/book20-thumbs/page-074.jpg Why Do Wolverines Wander So Far Across the Mountains? Wolverines wander far across the mountains because food is scattered! They are tough, powerful members of the weasel family. A wolverine may travel dozens of miles in a day. https://socialmedia.xdme.com/tony/videos-book20/page-074.mp4 https://www.youtube.com/embed/nN-EuL229Wk 113 2026-10-05T06:03:55+00:00 yes https://xdme.com/watch-book20-q075.html https://xdme.com/book20-thumbs/page-075.jpg How Does a Bird Help Plant Mountain Forests? A bird called Clark's nutcracker helps plant mountain forests! It hides seeds in the ground, and some are never found again. Those forgotten seeds grow into new trees. https://socialmedia.xdme.com/tony/videos-book20/page-075.mp4 https://www.youtube.com/embed/C3V2HtiI3JQ 120 2026-10-05T06:07:27+00:00 yes https://xdme.com/watch-book20-q076.html https://xdme.com/book20-thumbs/page-076.jpg Why Does Air Pressure Drop as You Go Up a Mountain? Air pressure drops as you go up a mountain because there is less air above you! Air has weight, even though you cannot see it. The higher you climb, the less air is stacked on top https://socialmedia.xdme.com/tony/videos-book20/page-076.mp4 https://www.youtube.com/embed/nx_b-GhwxaY 110 2026-10-05T03:09:12+00:00 yes https://xdme.com/watch-book20-q077.html https://xdme.com/book20-thumbs/page-077.jpg How Much Air Is There at the Top of Mount Everest? The air at the top of Mount Everest has the same kind of mix as air at the beach! It is still about 21 percent oxygen. The difference is that the air is so thin. https://socialmedia.xdme.com/tony/videos-book20/page-077.mp4 https://www.youtube.com/embed/lPql9MulHHM 114 2026-10-05T03:09:13+00:00 yes https://xdme.com/watch-book20-q078.html https://xdme.com/book20-thumbs/page-078.jpg Why Do Snack Bags Puff Up When You Drive Into the Mountains? Snack bags puff up in the mountains because the air outside gets thinner! A sealed bag keeps the air it had when it was packed. So when the pressure outside drops, the air inside p https://socialmedia.xdme.com/tony/videos-book20/page-078.mp4 https://www.youtube.com/embed/MAzP-rKC9eE 109 2026-10-05T03:09:30+00:00 yes https://xdme.com/watch-book20-q079.html https://xdme.com/book20-thumbs/page-079.jpg How Can a Watch Tell How High You Are? A watch can tell how high you are by feeling the air! Many hiking watches and phones have a tiny sensor called a barometer. It measures air pressure. https://socialmedia.xdme.com/tony/videos-book20/page-079.mp4 https://www.youtube.com/embed/6JxWSafFgeo 114 2026-10-05T03:10:33+00:00 yes https://xdme.com/watch-book20-q080.html https://xdme.com/book20-thumbs/page-080.jpg Why Do You Sunburn Faster in the Mountains? You sunburn faster in the mountains because the Sun's UV light is stronger up high! There is less air above you to block it. And snow makes it even stronger. https://socialmedia.xdme.com/tony/videos-book20/page-080.mp4 https://www.youtube.com/embed/fZ-KOY7tU0A 115 2026-10-05T03:10:34+00:00 yes https://xdme.com/watch-book20-q081.html https://xdme.com/book20-thumbs/page-081.jpg Why Does Wind Roar Through Mountain Passes? Wind roars through mountain passes because the air gets squeezed through a narrow gap! A pass is a low spot between two peaks. It acts like a funnel for the wind. https://socialmedia.xdme.com/tony/videos-book20/page-081.mp4 https://www.youtube.com/embed/b4x-L0IuJpQ 109 2026-10-05T03:10:36+00:00 yes https://xdme.com/watch-book20-q082.html https://xdme.com/book20-thumbs/page-082.jpg Why Does the Wind Blow Uphill During the Day and Downhill at Night? Mountain winds switch directions between day and night! In the day, the wind often blows uphill. At night, it flows downhill. Mountain breezes at night can feel cold on a valley fl https://socialmedia.xdme.com/tony/videos-book20/page-082.mp4 https://www.youtube.com/embed/T0VBu8L4jqI 115 2026-10-05T03:10:38+00:00 yes https://xdme.com/watch-book20-q083.html https://xdme.com/book20-thumbs/page-083.jpg What Is a Lenticular Cloud? A lenticular cloud is a smooth, round cloud shaped like a lens! Some people think it looks like a flying saucer. It forms when wind makes waves in the air over a mountain. https://socialmedia.xdme.com/tony/videos-book20/page-083.mp4 https://www.youtube.com/embed/qnuGQA4v0Vs 110 2026-10-05T03:10:40+00:00 yes https://xdme.com/watch-book20-q084.html https://xdme.com/book20-thumbs/page-084.jpg What Is a Banner Cloud? A banner cloud streams from a mountain peak like a flag flying in the wind! It appears on one side of a steep, pointed mountain. The cloud looks like it is waving. https://socialmedia.xdme.com/tony/videos-book20/page-084.mp4 https://www.youtube.com/embed/qfn1kJm3EnE 108 2026-10-05T03:10:41+00:00 yes https://xdme.com/watch-book20-q085.html https://xdme.com/book20-thumbs/page-085.jpg Why Do Hikers Start Early to Avoid Afternoon Storms? Hikers start early to avoid afternoon storms that build in the mountains! Mornings are usually calm and clear. The air has had all night to settle down. https://socialmedia.xdme.com/tony/videos-book20/page-085.mp4 https://www.youtube.com/embed/aS9wxexuaFc 118 2026-10-05T03:10:55+00:00 yes https://xdme.com/watch-book20-q086.html https://xdme.com/book20-thumbs/page-086.jpg How Does a Mountain Range Squeeze the Rain Out of the Wind? A mountain range squeezes the rain out of the wind like squeezing a wet sponge! Moist wind is forced to climb up the mountains. By the time it comes down the other side, it has los https://socialmedia.xdme.com/tony/videos-book20/page-086.mp4 https://www.youtube.com/embed/B8DsWTY-cLA 110 2026-10-05T03:10:56+00:00 yes https://xdme.com/watch-book20-q087.html https://xdme.com/book20-thumbs/page-087.jpg What Is the “Snow Eater” Wind That Melts Snow in Hours? The snow eater wind is called a chinook, and it melts snow in hours! A chinook is a warm, dry wind that blows down the eastern side of the Rocky Mountains. The word chinook means s https://socialmedia.xdme.com/tony/videos-book20/page-087.mp4 https://www.youtube.com/embed/Y8M0RetXHuk 119 2026-10-05T03:10:58+00:00 yes https://xdme.com/watch-book20-q088.html https://xdme.com/book20-thumbs/page-088.jpg Why Can Mountain Weather Change So Fast? Mountain weather can change fast because mountains stir up the air! Air is forced to rise, sink, and swirl around peaks and valleys. That makes the weather very changeable. https://socialmedia.xdme.com/tony/videos-book20/page-088.mp4 https://www.youtube.com/embed/fzjUVyrRKAI 117 2026-10-05T03:10:59+00:00 yes https://xdme.com/watch-book20-q089.html https://xdme.com/book20-thumbs/page-089.jpg Why Can a Valley Be Colder than the Slope Above It? A valley can be colder than the slope above it because cold air flows downhill! Cold air is heavy, so it slides down and pools in the valley. It is like water filling a bowl. https://socialmedia.xdme.com/tony/videos-book20/page-089.mp4 https://www.youtube.com/embed/EcremywNGBk 110 2026-10-05T03:11:33+00:00 yes https://xdme.com/watch-book20-q090.html https://xdme.com/book20-thumbs/page-090.jpg Why Does It Snow So Much More in the Mountains than in the Valleys? It snows so much more in the mountains because rising air cools and drops its water! Mountains push moist air upward. Higher up, it is colder, so more falls as snow. https://socialmedia.xdme.com/tony/videos-book20/page-090.mp4 https://www.youtube.com/embed/7hK_3Mkovn4 112 2026-10-05T03:13:35+00:00 yes https://xdme.com/watch-book20-q091.html https://xdme.com/book20-thumbs/page-091.jpg What Is a Mountain Weather Station? A mountain weather station is a robot helper that measures the weather for us! It sits on a peak or slope, powered by the Sun. It sends its measurements by radio. https://socialmedia.xdme.com/tony/videos-book20/page-091.mp4 https://www.youtube.com/embed/sh95nmypacY 119 2026-10-05T03:16:52+00:00 yes https://xdme.com/watch-book20-q092.html https://xdme.com/book20-thumbs/page-092.jpg Why Can It Snow in July on a Mountain? It can snow in July on a mountain because the air up high can be freezing, even in summer! The higher you go, the colder it gets. A passing storm can turn rain into snow. https://socialmedia.xdme.com/tony/videos-book20/page-092.mp4 https://www.youtube.com/embed/NJrr87d7Abw 111 2026-10-05T03:19:54+00:00 yes https://xdme.com/watch-book20-q093.html https://xdme.com/book20-thumbs/page-093.jpg What Is Alpenglow? Alpenglow is the pink-orange glow on snowy peaks just before sunrise or after sunset! It is one of the prettiest sights in the mountains, and it has been enjoyed for ages. And it o https://socialmedia.xdme.com/tony/videos-book20/page-093.mp4 https://www.youtube.com/embed/H_mS_B65eak 115 2026-10-05T03:22:31+00:00 yes https://xdme.com/watch-book20-q094.html https://xdme.com/book20-thumbs/page-094.jpg What Is a Brocken Spectre? A Brocken spectre is a giant shadow of you, cast on a cloud! It sounds spooky, but it is only science. The shadow is yours, made of light and mist. https://socialmedia.xdme.com/tony/videos-book20/page-094.mp4 https://www.youtube.com/embed/milXURQ_m7E 110 2026-10-05T03:25:05+00:00 yes https://xdme.com/watch-book20-q095.html https://xdme.com/book20-thumbs/page-095.jpg Why Is a Mountaintop a Bad Place to Be in a Thunderstorm? A mountaintop is a bad place to be in a thunderstorm because lightning strikes tall, high places! On a bare peak, a person may be the tallest thing around. So the safe plan is to b https://socialmedia.xdme.com/tony/videos-book20/page-095.mp4 https://www.youtube.com/embed/vBKPfLldptU 111 2026-10-05T03:28:11+00:00 yes https://xdme.com/watch-book20-q096.html https://xdme.com/book20-thumbs/page-096.jpg Can You Walk Inside a Cloud? Yes, you can walk inside a cloud! A cloud is just a mass of tiny water droplets, the same as fog. So when a cloud rolls over a mountain trail, you are inside it. https://socialmedia.xdme.com/tony/videos-book20/page-096.mp4 https://www.youtube.com/embed/Vv12iimmXqI 115 2026-10-05T03:30:42+00:00 yes https://xdme.com/watch-book20-q097.html https://xdme.com/book20-thumbs/page-097.jpg Why Does a Ball Fly Farther at High Altitude? A ball flies farther at high altitude because the air is thinner! Air pushes back on anything that moves through it. Up high, there is less air to push back. https://socialmedia.xdme.com/tony/videos-book20/page-097.mp4 https://www.youtube.com/embed/8fo14Lz4mhw 108 2026-10-05T03:33:52+00:00 yes https://xdme.com/watch-book20-q098.html https://xdme.com/book20-thumbs/page-098.jpg Why Do Airplanes Need Longer Runways at High Airports? Airplanes need longer runways at high airports because the air is thin! Planes need to reach a certain speed to lift off. In thin air, that takes longer. https://socialmedia.xdme.com/tony/videos-book20/page-098.mp4 https://www.youtube.com/embed/ZBeRoZHkPzE 115 2026-10-05T03:37:08+00:00 yes https://xdme.com/watch-book20-q099.html https://xdme.com/book20-thumbs/page-099.jpg Why Is It So Hard to Forecast Mountain Weather? Mountain weather is hard to forecast because mountains make big changes in a short distance! A sunny valley and a stormy ridge may be only a few miles apart. Even experts can be su https://socialmedia.xdme.com/tony/videos-book20/page-099.mp4 https://www.youtube.com/embed/fbQkJpWiTu4 117 2026-10-05T03:39:48+00:00 yes https://xdme.com/watch-book20-q100.html https://xdme.com/book20-thumbs/page-100.jpg What Are the Tiny White Pellets That Fall in Mountain Storms? The tiny white pellets that fall in mountain storms are called graupel! They look like tiny foam balls, and they are soft and crumbly. Graupel is common in cool mountain showers. https://socialmedia.xdme.com/tony/videos-book20/page-100.mp4 https://www.youtube.com/embed/_GKNvKGdB-U 115 2026-10-05T03:42:50+00:00 yes https://xdme.com/watch-book20-q101.html https://xdme.com/book20-thumbs/page-101.jpg How Does Snow Pile Up Into Layers on a Mountain? Snow piles up into layers because every storm adds a new one! Between storms, wind, sunshine, and cold change the snow's surface. Then new snow buries it, and the whole stack is ca https://socialmedia.xdme.com/tony/videos-book20/page-101.mp4 https://www.youtube.com/embed/RFwNkEzKj5o 112 2026-10-05T03:45:57+00:00 yes https://xdme.com/watch-book20-q102.html https://xdme.com/book20-thumbs/page-102.jpg Why Do Snow Scientists Dig Pits in the Snow? Snow scientists dig pits so they can see inside the snowpack! A pit works like a window, because the wall shows every layer in a cross-section. Only trained experts dig and test in https://socialmedia.xdme.com/tony/videos-book20/page-102.mp4 https://www.youtube.com/embed/_VhZGayGwZ4 111 2026-10-05T03:48:34+00:00 yes https://xdme.com/watch-book20-q103.html https://xdme.com/book20-thumbs/page-103.jpg Why Does a Whole Layer of Snow Sometimes Let Go and Slide? Sometimes a whole layer of snow lets go because it is sitting on a weak layer underneath. When it slides all at once, that is called an avalanche. Let's talk about it calmly, becau https://socialmedia.xdme.com/tony/videos-book20/page-103.mp4 https://www.youtube.com/embed/nz2mwzuTAFI 117 2026-10-05T03:51:44+00:00 yes https://xdme.com/watch-book20-q104.html https://xdme.com/book20-thumbs/page-104.jpg How Do Avalanche Forecasters Keep People Safe? Avalanche forecasters keep people safe by studying the snow and the weather. Then they tell everyone how dangerous the mountains are that day. It is like a weather forecast, but fo https://socialmedia.xdme.com/tony/videos-book20/page-104.mp4 https://www.youtube.com/embed/Waa5wSohaTI 116 2026-10-05T03:54:18+00:00 yes https://xdme.com/watch-book20-q105.html https://xdme.com/book20-thumbs/page-105.jpg What Is a Cornice? A cornice is a big overhanging lip of snow that wind builds along a mountain ridge. It looks a bit like a frozen ocean wave, curling out into the air. Cornices can break off withou https://socialmedia.xdme.com/tony/videos-book20/page-105.mp4 https://www.youtube.com/embed/qN70Wj2PuSk 112 2026-10-05T03:57:08+00:00 yes https://xdme.com/watch-book20-q106.html https://xdme.com/book20-thumbs/page-106.jpg How Does a Glacier Form High on a Mountain? A glacier forms in high places where more snow falls in winter than melts in summer. Year after year, the snow piles up and gets squashed by its own weight. Eventually it turns int https://socialmedia.xdme.com/tony/videos-book20/page-106.mp4 https://www.youtube.com/embed/K3tVw0xZ0rg 120 2026-10-05T04:00:44+00:00 yes https://xdme.com/watch-book20-q107.html https://xdme.com/book20-thumbs/page-107.jpg What Carved the Giant Bowls Near Mountaintops? Glaciers carve bowl-shaped hollows near mountaintops, and the bowls are called cirques. They look like giant armchairs carved right into the mountain. Ice moves very slowly, yet it https://socialmedia.xdme.com/tony/videos-book20/page-107.mp4 https://www.youtube.com/embed/4wdAs3UCPkQ 114 2026-10-05T04:05:48+00:00 yes https://xdme.com/watch-book20-q108.html https://xdme.com/book20-thumbs/page-108.jpg What Are Moraines, the Rubble Ridges Left by Melting Glaciers? Moraines are rubble ridges left behind by glaciers. As a glacier moves, it carries stones, gravel, and dust. When it melts or stops, it drops everything it was carrying. https://socialmedia.xdme.com/tony/videos-book20/page-108.mp4 https://www.youtube.com/embed/D69eKNXzEv0 112 2026-10-05T04:09:22+00:00 yes https://xdme.com/watch-book20-q109.html https://xdme.com/book20-thumbs/page-109.jpg How Do Scientists Measure Whether a Mountain Glacier Is Growing or Shrinking? Scientists can tell if a mountain glacier is growing or shrinking by keeping careful track of its ice. They use stakes, photos, GPS, and even lasers on airplanes. It is like checki https://socialmedia.xdme.com/tony/videos-book20/page-109.mp4 https://www.youtube.com/embed/LQIxh_oKqrs 112 2026-10-05T04:13:03+00:00 yes https://xdme.com/watch-book20-q110.html https://xdme.com/book20-thumbs/page-110.jpg Why Do Cliffs Have Piles of Broken Rock at Their Feet? Cliffs have piles of broken rock at their feet because pieces keep falling off the cliff above. The pieces collect in sloping piles called scree or talus. It is the mountain slowly https://socialmedia.xdme.com/tony/videos-book20/page-110.mp4 https://www.youtube.com/embed/uKD5FMm2f1s 112 2026-10-05T04:16:38+00:00 yes https://xdme.com/watch-book20-q111.html https://xdme.com/book20-thumbs/page-111.jpg Why Do Big Granite Domes Peel Like Onions? Big granite domes peel like onions because the rock swells and cracks into curved sheets. Scientists call this peeling exfoliation. It happens very slowly, over thousands of years. https://socialmedia.xdme.com/tony/videos-book20/page-111.mp4 https://www.youtube.com/embed/YrSKM575miU 112 2026-10-05T04:17:12+00:00 yes https://xdme.com/watch-book20-q112.html https://xdme.com/book20-thumbs/page-112.jpg Why Do Some Mountain Rocks Look Like Wavy Ribbons? Some mountain rocks look like wavy ribbons because their layers were folded. Earth's crust squeezed them from the sides, like pushing on a rug. It happened slowly, over millions of https://socialmedia.xdme.com/tony/videos-book20/page-112.mp4 https://www.youtube.com/embed/cR9h_zekwU4 113 2026-10-05T04:17:13+00:00 yes https://xdme.com/watch-book20-q113.html https://xdme.com/book20-thumbs/page-113.jpg How Did a Giant Boulder Get to a Place Where It Doesn’t Belong? A giant boulder can end up far from home because a glacier carried it there. When the ice melted, the boulder was dropped, all alone. These lonely boulders are called erratics. https://socialmedia.xdme.com/tony/videos-book20/page-113.mp4 https://www.youtube.com/embed/_9xXw8GZAQ8 117 2026-10-05T04:19:50+00:00 yes https://xdme.com/watch-book20-q114.html https://xdme.com/book20-thumbs/page-114.jpg Why Are Some Mountain Cliffs Red, Green, or Yellow? Mountain cliffs can be red, green, or yellow because of the minerals inside the rock. Different minerals make different colors. Layers of rock can show up as colorful stripes. https://socialmedia.xdme.com/tony/videos-book20/page-114.mp4 https://www.youtube.com/embed/7uDiZa2vodU 112 2026-10-05T04:23:32+00:00 yes https://xdme.com/watch-book20-q115.html https://xdme.com/book20-thumbs/page-115.jpg What Are Hoodoos? Hoodoos are tall, skinny towers of rock with a harder cap on top. Rain, ice, and wind carve them slowly. They take thousands of years to form, so each one is very old. https://socialmedia.xdme.com/tony/videos-book20/page-115.mp4 https://www.youtube.com/embed/eBUsSDOfti0 110 2026-10-05T04:28:06+00:00 yes https://xdme.com/watch-book20-q116.html https://xdme.com/book20-thumbs/page-116.jpg Why Do Rocks Sometimes Tumble Off Cliffs? Rocks sometimes tumble off cliffs because water, roots, and gravity slowly loosen them. Rockfalls are a normal part of how mountains change, but they can be dangerous. https://socialmedia.xdme.com/tony/videos-book20/page-116.mp4 https://www.youtube.com/embed/7c-4yvxNuCM 115 2026-10-05T04:31:40+00:00 yes https://xdme.com/watch-book20-q117.html https://xdme.com/book20-thumbs/page-117.jpg What Is a Rock Glacier? A rock glacier is a slow-moving river of broken rock and ice, shaped like a tongue. It creeps downhill just a few inches or feet each year. From far away, it looks like a giant pil https://socialmedia.xdme.com/tony/videos-book20/page-117.mp4 https://www.youtube.com/embed/QpI7UeebatE 107 2026-10-05T04:32:25+00:00 yes https://xdme.com/watch-book20-q118.html https://xdme.com/book20-thumbs/page-118.jpg Why Do Some Mountain Forests Have Bare Stripes? Some mountain forests have long, bare stripes running through them. These stripes are avalanche paths, where snow slides down often and clears away the trees. https://socialmedia.xdme.com/tony/videos-book20/page-118.mp4 https://www.youtube.com/embed/e2Uo1ov2n1w 111 2026-10-05T04:40:18+00:00 yes https://xdme.com/watch-book20-q119.html https://xdme.com/book20-thumbs/page-119.jpg Where Is the Line Above Which Snow Never Melts Away? The snow line is the height above which snow stays on the ground all year. On a mountain, you may see a clear line where bare ground meets white snow in summer. https://socialmedia.xdme.com/tony/videos-book20/page-119.mp4 https://www.youtube.com/embed/Coh6zresyiE 105 2026-10-05T05:30:21+00:00 yes https://xdme.com/watch-book20-q120.html https://xdme.com/book20-thumbs/page-120.jpg Why Is Snow in the Rockies So Light and Fluffy? Snow in the Rockies is often light and fluffy because the air there is very cold and dry. Skiers love it, and they call it powder, because it feels almost like flour. https://socialmedia.xdme.com/tony/videos-book20/page-120.mp4 https://www.youtube.com/embed/vDM4sNCJpQg 108 2026-10-05T05:30:22+00:00 yes https://xdme.com/watch-book20-q121.html https://xdme.com/book20-thumbs/page-121.jpg Why Are Mountains Called Water Towers? Mountains are called water towers because they store water high up, like a tower. They hold winter snow and release it later as it melts. That water flows down to rivers, farms, an https://socialmedia.xdme.com/tony/videos-book20/page-121.mp4 https://www.youtube.com/embed/Mfl_kr6-DJo 114 2026-10-05T05:55:14+00:00 yes https://xdme.com/watch-book20-q122.html https://xdme.com/book20-thumbs/page-122.jpg How Can Scientists Measure Snow in Inches of Water? Scientists can measure snow in inches of water because snow is mostly air. They find out how much water is hidden inside the snow. This is called snow water equivalent. https://socialmedia.xdme.com/tony/videos-book20/page-122.mp4 https://www.youtube.com/embed/Hrn3EBb34k0 109 2026-10-05T05:55:17+00:00 yes https://xdme.com/watch-book20-q123.html https://xdme.com/book20-thumbs/page-123.jpg Why Do Mountain Streams Run Higher in the Late Afternoon? Mountain streams run higher in the late afternoon because the Sun melts snow and ice all day. The meltwater takes time to flow down the slopes. So the stream rises long after the m https://socialmedia.xdme.com/tony/videos-book20/page-123.mp4 https://www.youtube.com/embed/i-mdQAJaCQI 110 2026-10-05T05:55:20+00:00 yes https://xdme.com/watch-book20-q124.html https://xdme.com/book20-thumbs/page-124.jpg Why Are Some of the Oldest Weird Animal Fossils Found High in the Rocky Mountains? Some of the oldest, weirdest animal fossils are found high in the Rocky Mountains. The Burgess Shale, in Yoho National Park, holds fossils about 508 million years old. How did sea https://socialmedia.xdme.com/tony/videos-book20/page-124.mp4 https://www.youtube.com/embed/Fzta7E61Xoo 116 2026-10-05T05:55:21+00:00 yes https://xdme.com/watch-book20-q125.html https://xdme.com/book20-thumbs/page-125.jpg How Can You Read a Mountain’s History From Its Shape? You can read a mountain's history from its shape, because every shape is a clue. It is like reading a book written in rock, with no words at all. Let's learn the clues. https://socialmedia.xdme.com/tony/videos-book20/page-125.mp4 https://www.youtube.com/embed/gC0laM2ZRpI 110 2026-10-05T05:55:22+00:00 yes https://xdme.com/watch-book20-q126.html https://xdme.com/book20-thumbs/page-126.jpg Why Do Mountain Trails Zigzag Back and Forth? Mountain trails zigzag back and forth because a straight climb up a steep slope would be exhausting. The zigzags are called switchbacks. They make the climb gentler for legs, lungs https://socialmedia.xdme.com/tony/videos-book20/page-126.mp4 https://www.youtube.com/embed/_03u-gQ90oA 111 2026-10-05T05:55:27+00:00 yes https://xdme.com/watch-book20-q127.html https://xdme.com/book20-thumbs/page-127.jpg How Does a Contour Map Show a Mountain? A contour map shows a mountain's height using curvy lines. Each line connects places that are the same height. Hikers read contour lines to picture the land, even before they arriv https://socialmedia.xdme.com/tony/videos-book20/page-127.mp4 https://www.youtube.com/embed/SQyVMSBFBnE 112 2026-10-05T05:55:29+00:00 yes https://xdme.com/watch-book20-q128.html https://xdme.com/book20-thumbs/page-128.jpg What Are Cairns and Trail Blazes? Cairns and trail blazes are markers that help hikers stay on the path. A cairn is a small pile of stacked rocks. A blaze is a painted mark on a tree. https://socialmedia.xdme.com/tony/videos-book20/page-128.mp4 https://www.youtube.com/embed/ud8MGkuSde0 109 2026-10-05T05:55:30+00:00 yes https://xdme.com/watch-book20-q129.html https://xdme.com/book20-thumbs/page-129.jpg How Does a Gondola Lift Get Up the Mountain? A gondola lift gets up the mountain by hanging cabins from a moving cable loop. A big electric motor keeps the cable moving. It is like a giant clothesline that carries people uphi https://socialmedia.xdme.com/tony/videos-book20/page-129.mp4 https://www.youtube.com/embed/zxQV0o81CAc 107 2026-10-05T05:55:38+00:00 yes https://xdme.com/watch-book20-q130.html https://xdme.com/book20-thumbs/page-130.jpg How Does a Chairlift Work? A chairlift is a loop of cable with chairs attached. A motor turns the cable at a steady speed. It carries skiers and hikers up the mountain, so nobody has to climb the slope. https://socialmedia.xdme.com/tony/videos-book20/page-130.mp4 https://www.youtube.com/embed/4ZXMoEYX6cM 110 2026-10-05T05:55:39+00:00 yes https://xdme.com/watch-book20-q131.html https://xdme.com/book20-thumbs/page-131.jpg How Do Cog Railways and Funiculars Climb Slopes That Normal Trains Can’t? Cog railways and funiculars climb slopes that normal trains cannot. Normal train wheels would slip on a steep track, like boots on wet ice. So these railways use clever tricks to g https://socialmedia.xdme.com/tony/videos-book20/page-131.mp4 https://www.youtube.com/embed/9CedbforD1I 112 2026-10-05T05:55:40+00:00 yes https://xdme.com/watch-book20-q132.html https://xdme.com/book20-thumbs/page-132.jpg How Do Ski Areas Make Snow? Ski areas make snow with machines called snow guns. They spray tiny droplets of water into very cold air. The droplets freeze into small ice crystals before they land, just like na https://socialmedia.xdme.com/tony/videos-book20/page-132.mp4 https://www.youtube.com/embed/Ox9kSn3dCKI 112 2026-10-05T06:01:55+00:00 yes https://xdme.com/watch-book20-q133.html https://xdme.com/book20-thumbs/page-133.jpg Why Do Skis Slide So Well on Snow? Skis slide so well on snow because of a very thin layer of water. It forms on the surface where the ski rubs the snow. That slippery film works a bit like oil on a bike chain. https://socialmedia.xdme.com/tony/videos-book20/page-133.mp4 https://www.youtube.com/embed/lkQ-U1wZ0yA 105 2026-10-05T06:02:00+00:00 yes https://xdme.com/watch-book20-q134.html https://xdme.com/book20-thumbs/page-134.jpg How Do Trains Spiral Inside a Mountain? Trains can spiral inside a mountain by riding through curved tunnels that loop around. In 1909, builders in the Canadian Rockies dug two spiral tunnels at Kicking Horse Pass. https://socialmedia.xdme.com/tony/videos-book20/page-134.mp4 https://www.youtube.com/embed/VLcBOvEUlFc 108 2026-10-05T06:02:02+00:00 yes https://xdme.com/watch-book20-q135.html https://xdme.com/book20-thumbs/page-135.jpg Why Do Some Mountain Highways Have Long Roofs Called Snow Sheds? Some mountain highways have long roofs called snow sheds. They protect the road from snow that slides down steep slopes, so cars and trucks can keep moving. https://socialmedia.xdme.com/tony/videos-book20/page-135.mp4 https://www.youtube.com/embed/1JTmPOmirUY 113 2026-10-05T06:02:04+00:00 yes https://xdme.com/watch-book20-q136.html https://xdme.com/book20-thumbs/page-136.jpg Why Is It Important to Drink Water and Snack on a Mountain Hike? It is important to drink water and snack on a mountain hike, because your body works hard up there. You lose water, and you use lots of energy on the climb. https://socialmedia.xdme.com/tony/videos-book20/page-136.mp4 https://www.youtube.com/embed/07UUw1885kE 109 2026-10-05T06:02:05+00:00 yes https://xdme.com/watch-book20-q137.html https://xdme.com/book20-thumbs/page-137.jpg Why Do Hikers Carry the “Ten Essentials”? Hikers carry the ten essentials because they help everyone stay safe if plans change. They are small items that can matter a lot, and they all fit in a daypack. Kids hike with grow https://socialmedia.xdme.com/tony/videos-book20/page-137.mp4 https://www.youtube.com/embed/7bP1trFoAXY 112 2026-10-05T06:02:06+00:00 yes https://xdme.com/watch-book20-q138.html https://xdme.com/book20-thumbs/page-138.jpg Why Do Mountain Trails Have Steps, Boardwalks, and Little Ditches? Mountain trails have steps, boardwalks, and little ditches to protect the land. Busy trails can wear away, because thousands of boots and lots of rain push the soil around. Trail b https://socialmedia.xdme.com/tony/videos-book20/page-138.mp4 https://www.youtube.com/embed/pccPnHKCi9o 114 2026-10-05T06:02:08+00:00 yes https://xdme.com/watch-book20-q139.html https://xdme.com/book20-thumbs/page-139.jpg Why Is Alpine Tundra So Easily Damaged? Alpine tundra is easily damaged because the plants grow very slowly. Summers are short, and the soils are thin and rocky. A trampled plant can take years, even decades, to recover. https://socialmedia.xdme.com/tony/videos-book20/page-139.mp4 https://www.youtube.com/embed/vv3qTlnMTnA 111 2026-10-05T06:02:10+00:00 yes https://xdme.com/watch-book20-q140.html https://xdme.com/book20-thumbs/page-140.jpg What Does “Leave No Trace” Mean? Leave no trace means visiting nature without leaving signs that you were there. It helps the outdoors stay wild and beautiful for animals, plants, and the next visitors. Here are t https://socialmedia.xdme.com/tony/videos-book20/page-140.mp4 https://www.youtube.com/embed/UMsr5ckuCa4 107 2026-10-05T06:02:42+00:00 yes https://xdme.com/watch-book20-q141.html https://xdme.com/book20-thumbs/page-141.jpg How Do Hikers Stay Safe Around Mountain Wildlife? Hikers stay safe around mountain wildlife by giving animals plenty of space. Wild animals need room to eat, rest, and raise their young, and they can be unpredictable. Here is how https://socialmedia.xdme.com/tony/videos-book20/page-141.mp4 https://www.youtube.com/embed/EPCeVJlaWmY 118 2026-10-05T06:02:43+00:00 yes https://xdme.com/watch-book20-q142.html https://xdme.com/book20-thumbs/page-142.jpg Why Do Hikers Set a Turnaround Time? Hikers set a turnaround time to help everyone get home safely. It is a clock time when the group agrees to head back, even if they have not reached the top. That is a smart plan, n https://socialmedia.xdme.com/tony/videos-book20/page-142.mp4 https://www.youtube.com/embed/kHEFxpWCGlk 105 2026-10-05T06:02:44+00:00 yes https://xdme.com/watch-book20-q143.html https://xdme.com/book20-thumbs/page-143.jpg What Jobs Help Keep Mountains Safe and Fun? Lots of different jobs help keep mountains safe and fun. Each person helps visitors enjoy the mountains and helps protect the land, the plants, and the animals. Let's meet some of https://socialmedia.xdme.com/tony/videos-book20/page-143.mp4 https://www.youtube.com/embed/sEQOqwcTl6o 116 2026-10-05T06:02:46+00:00 yes https://xdme.com/watch-book20-q144.html https://xdme.com/book20-thumbs/page-144.jpg How Do Mountain Huts Stay Warm and Stocked? Remote mountain huts stay warm and stocked with help from people and machines. A hut is a small cabin where hikers can sleep and eat. https://socialmedia.xdme.com/tony/videos-book20/page-144.mp4 https://www.youtube.com/embed/9_lgjrGSOAM 110 2026-10-05T06:02:48+00:00 yes https://xdme.com/watch-book20-q145.html https://xdme.com/book20-thumbs/page-145.jpg Why Do Mountains Look Closer than They Really Are? Mountains look closer than they really are because of clear mountain air and their huge size. Your eyes can be fooled by big things that are far away, and that is perfectly normal. https://socialmedia.xdme.com/tony/videos-book20/page-145.mp4 https://www.youtube.com/embed/lQ-QF4p_MKo 105 2026-10-05T06:02:50+00:00 yes https://xdme.com/watch-book20-q146.html https://xdme.com/book20-thumbs/page-146.jpg What Should a Kid Do If They Get Separated From Their Group on a Trail? If a kid gets separated from their group on a trail, the most important rule is to stop and stay put. Staying calm and staying where you are helps grown-ups find you quickly. Let's https://socialmedia.xdme.com/tony/videos-book20/page-146.mp4 https://www.youtube.com/embed/Zm1H3bkdom4 107 2026-10-05T06:02:51+00:00 yes https://xdme.com/watch-book20-q147.html https://xdme.com/book20-thumbs/page-147.jpg How Can You Enjoy Mountains in Every Season? You can enjoy mountains in every season, because each season shows something different. With the right clothes, a plan, and a grown-up, there is always something to discover. https://socialmedia.xdme.com/tony/videos-book20/page-147.mp4 https://www.youtube.com/embed/vpTMYCVIhBA 118 2026-10-05T06:02:52+00:00 yes https://xdme.com/watch-book20-q148.html https://xdme.com/book20-thumbs/page-148.jpg How Do Wolves and Bears Get Across the Trans-Canada Highway in Banff? Wolves and bears get across the Trans-Canada Highway in Banff by using wildlife crossings. There are tunnels under the road and grassy bridges over it. https://socialmedia.xdme.com/tony/videos-book20/page-148.mp4 https://www.youtube.com/embed/ce-k1uNsvzc 120 2026-10-05T06:02:54+00:00 yes https://xdme.com/watch-book20-q149.html https://xdme.com/book20-thumbs/page-149.jpg How Can You Be a Mountain Scientist? You can be a mountain scientist, and you can start anywhere! You do not need a mountain to begin, only curiosity and a notebook, and a backyard or park works great. Here are three https://socialmedia.xdme.com/tony/videos-book20/page-149.mp4 https://www.youtube.com/embed/-NDhmoKC4f8 112 2026-10-05T06:03:56+00:00 yes https://xdme.com/watch-book20-q150.html https://xdme.com/book20-thumbs/page-150.jpg What Mountain Puzzles Are Left to Solve? Mountains still hold mysteries that scientists have not solved yet. There are big puzzles waiting for curious people, in every range, from the Rockies to the Himalayas. Maybe you w https://socialmedia.xdme.com/tony/videos-book20/page-150.mp4 https://www.youtube.com/embed/Lc8Y281L4_0 119 2026-10-05T06:07:29+00:00 yes https://xdme.com/watch-book21-q001.html https://xdme.com/book21-thumbs/page-001.jpg What Is a Magnetic Field, and Why Can’t We See It? A magnetic field is the invisible space around a magnet where its push and pull can reach. You cannot see it, because it is not made of light or of anything you can touch. But we c https://socialmedia.xdme.com/tony/videos-book21/page-001.mp4 https://www.youtube.com/embed/Sj2uQf4-C6I 114 2026-10-05T06:10:15+00:00 yes https://xdme.com/watch-book21-q002.html https://xdme.com/book21-thumbs/page-002.jpg Why Do Magnets Have Two Ends Called Poles? Every magnet has two poles, called north and south. They are the places where its pulling power is strongest. Every magnet has exactly two poles. https://socialmedia.xdme.com/tony/videos-book21/page-002.mp4 https://www.youtube.com/embed/0M3DD75a7WQ 109 2026-10-05T06:11:18+00:00 yes https://xdme.com/watch-book21-q003.html https://xdme.com/book21-thumbs/page-003.jpg Why Do Opposite Poles Attract but Matching Poles Push Apart? Opposite poles pull together, but matching poles push apart. The secret is in the direction of a magnet's field. Electric charges follow a similar rule: opposite charges attract. https://socialmedia.xdme.com/tony/videos-book21/page-003.mp4 https://www.youtube.com/embed/ubSynpdKGxU 115 2026-10-05T06:11:19+00:00 yes https://xdme.com/watch-book21-q004.html https://xdme.com/book21-thumbs/page-004.jpg What Happens If You Cut a Magnet in Half? If you cut a magnet in half, you do not get a north piece and a south piece. You get two smaller magnets, and each one has its own north and south pole! https://socialmedia.xdme.com/tony/videos-book21/page-004.mp4 https://www.youtube.com/embed/xahzE_xZhiI 108 2026-10-05T06:11:20+00:00 yes https://xdme.com/watch-book21-q005.html https://xdme.com/book21-thumbs/page-005.jpg Why Is a Magnet’s Pull Strongest at Its Ends? A bar magnet pulls hardest at its two ends and weakest in its middle. That happens because of what the tiny groups inside are doing. https://socialmedia.xdme.com/tony/videos-book21/page-005.mp4 https://www.youtube.com/embed/-ZJX-jHLZjA 110 2026-10-05T06:12:03+00:00 yes https://xdme.com/watch-book21-q006.html https://xdme.com/book21-thumbs/page-006.jpg How Far Away Can a Magnet Reach? A magnet's field never stops all at once, but it fades very quickly with distance. A small fridge magnet might only reach a paper clip a few inches away. https://socialmedia.xdme.com/tony/videos-book21/page-006.mp4 https://www.youtube.com/embed/vXm_be7FrXc 111 2026-10-05T06:14:37+00:00 yes https://xdme.com/watch-book21-q007.html https://xdme.com/book21-thumbs/page-007.jpg Why Can a Magnet Work Through Paper, Water, and Even Your Hand? A magnetic field passes right through most things that are not magnetic. That includes paper, plastic, wood, glass, water, and even your skin. https://socialmedia.xdme.com/tony/videos-book21/page-007.mp4 https://www.youtube.com/embed/G_qv46uKYA0 112 2026-10-05T06:20:14+00:00 yes https://xdme.com/watch-book21-q008.html https://xdme.com/book21-thumbs/page-008.jpg What Are Magnetic Field Lines? Magnetic field lines are imaginary curved lines that scientists draw. They show the shape and direction of a magnetic field. Think of them as a map of the invisible. https://socialmedia.xdme.com/tony/videos-book21/page-008.mp4 https://www.youtube.com/embed/bh9D7jJ3M_Q 108 2026-10-05T06:24:17+00:00 yes https://xdme.com/watch-book21-q009.html https://xdme.com/book21-thumbs/page-009.jpg How Can Iron Filings Show the Shape of a Magnet’s Field? Iron filings are tiny slivers of iron, like very fine metal dust. Around a magnet, they line up to draw the shape of its field. Photographs of iron-filing patterns have helped peop https://socialmedia.xdme.com/tony/videos-book21/page-009.mp4 https://www.youtube.com/embed/0SIQWQ0bE1M 111 2026-10-05T06:27:20+00:00 yes https://xdme.com/watch-book21-q010.html https://xdme.com/book21-thumbs/page-010.jpg How Can a Magnet Turn a Paper Clip Into a Tiny Magnet? Paper clips are steel, and steel has iron in it. Next to a magnet, it can become a tiny magnet itself! A paper clip is made of steel, which contains iron. https://socialmedia.xdme.com/tony/videos-book21/page-010.mp4 https://www.youtube.com/embed/lf2rGdVvXKs 111 2026-10-05T06:30:23+00:00 yes https://xdme.com/watch-book21-q011.html https://xdme.com/book21-thumbs/page-011.jpg What Tiny Neighborhoods Inside Iron Decide If It Is a Magnet? Inside a piece of iron are tiny neighborhoods called domains. Each domain holds millions of atoms that all point their magnetic directions the same way. Whether the iron is a magne https://socialmedia.xdme.com/tony/videos-book21/page-011.mp4 https://www.youtube.com/embed/HT-emfloyX8 116 2026-10-05T06:33:56+00:00 yes https://xdme.com/watch-book21-q012.html https://xdme.com/book21-thumbs/page-012.jpg Why Do Some Magnets Lose Their Power Over Time? Magnets do not last forever. A magnet gets weaker when the domains inside it get scrambled. Many fridge magnets last for years. But a dropped or heated one can weaken fast. https://socialmedia.xdme.com/tony/videos-book21/page-012.mp4 https://www.youtube.com/embed/A5TwV7y2mbw 115 2026-10-05T06:36:59+00:00 yes https://xdme.com/watch-book21-q013.html https://xdme.com/book21-thumbs/page-013.jpg What Is the Difference Between a Permanent Magnet and a Temporary Magnet? A permanent magnet keeps its magnetism for a long time. A temporary magnet acts like a magnet only while another magnet is nearby. Let's meet them both! https://socialmedia.xdme.com/tony/videos-book21/page-013.mp4 https://www.youtube.com/embed/CJm6dj-p1Jo 117 2026-10-05T06:40:02+00:00 yes https://xdme.com/watch-book21-q014.html https://xdme.com/book21-thumbs/page-014.jpg How Do Scientists Measure How Strong a Magnet Is? Scientists have special tools that measure how strong a magnetic field is. They read the strength in units called gauss or tesla. You can compare magnets at home too, using nothing https://socialmedia.xdme.com/tony/videos-book21/page-014.mp4 https://www.youtube.com/embed/2Ae5UukPWO8 115 2026-10-05T06:43:04+00:00 yes https://xdme.com/watch-book21-q015.html https://xdme.com/book21-thumbs/page-015.jpg Why Do Two Magnets Seem to Jump Together at the Last Moment? Have you ever felt two magnets jump together at the last moment? A magnet's pull grows stronger very quickly as the magnets get closer. https://socialmedia.xdme.com/tony/videos-book21/page-015.mp4 https://www.youtube.com/embed/ZBNeyFnudUM 111 2026-10-05T06:46:07+00:00 yes https://xdme.com/watch-book21-q016.html https://xdme.com/book21-thumbs/page-016.jpg Why Does One Magnet Seem to Float Above Another? When you stack ring magnets with matching poles facing, the top one seems to float! The magnets push each other apart, and that push holds the top one up. https://socialmedia.xdme.com/tony/videos-book21/page-016.mp4 https://www.youtube.com/embed/J_8foD9sKfU 113 2026-10-05T06:49:10+00:00 yes https://xdme.com/watch-book21-q017.html https://xdme.com/book21-thumbs/page-017.jpg Can a Magnet Have Only One Pole? So far, no one has ever found a magnet with just one pole. Every magnet ever made or found has both a north and a south pole. A single magnetic pole is called a monopole. https://socialmedia.xdme.com/tony/videos-book21/page-017.mp4 https://www.youtube.com/embed/guOAwk7iGGo 106 2026-10-05T06:52:12+00:00 yes https://xdme.com/watch-book21-q018.html https://xdme.com/book21-thumbs/page-018.jpg How Did the Poles of a Magnet Get the Names North and South? The names north pole and south pole come from how a magnet points on Earth. Long ago, people noticed something about a magnet that could swing freely. Their clue turned into the na https://socialmedia.xdme.com/tony/videos-book21/page-018.mp4 https://www.youtube.com/embed/9rXdqNZRVTM 116 2026-10-05T06:55:14+00:00 yes https://xdme.com/watch-book21-q019.html https://xdme.com/book21-thumbs/page-019.jpg How Is Magnetic Force Different From Gravity? Magnetic force and gravity are both invisible forces, but they act in different ways. Gravity only pulls, while magnetism can pull or push. Gravity keeps your feet on the ground, a https://socialmedia.xdme.com/tony/videos-book21/page-019.mp4 https://www.youtube.com/embed/GSm8D0oRVTo 123 2026-10-05T06:58:47+00:00 yes https://xdme.com/watch-book21-q020.html https://xdme.com/book21-thumbs/page-020.jpg Why Does the Pull of a Magnet Get Stronger When It Is Closer? A magnet pulls harder when it is closer for the same reason a flashlight looks brighter up close. Magnetic fields spread out in all directions as they leave the poles. https://socialmedia.xdme.com/tony/videos-book21/page-020.mp4 https://www.youtube.com/embed/zCzMSDVaSlY 111 2026-10-05T07:01:50+00:00 yes https://xdme.com/watch-book21-q021.html https://xdme.com/book21-thumbs/page-021.jpg Is Magnetism the Same as Electricity? Magnetism and electricity are two sides of one force, called electromagnetism. They are closely connected, but they are not the same thing. A fridge magnet, for example, needs no w https://socialmedia.xdme.com/tony/videos-book21/page-021.mp4 https://www.youtube.com/embed/G2itE9oPhFA 121 2026-10-05T07:05:01+00:00 yes https://xdme.com/watch-book21-q022.html https://xdme.com/book21-thumbs/page-022.jpg What Are the Strongest Magnets in the World? Some magnets are small enough to fit in your hand, and some are as big as a room. The strongest everyday magnets are made of neodymium, iron, and boron. Let's climb a ladder of mag https://socialmedia.xdme.com/tony/videos-book21/page-022.mp4 https://www.youtube.com/embed/u6PcJ-oufYc 119 2026-10-05T07:09:16+00:00 yes https://xdme.com/watch-book21-q023.html https://xdme.com/book21-thumbs/page-023.jpg Why Do Two Magnets Pushing Apart Feel Like Pressing on a Springy Cushion? Push two magnets together with matching poles facing, and something strange happens. It feels like you are pressing on a springy cushion, even though nothing is touching! https://socialmedia.xdme.com/tony/videos-book21/page-023.mp4 https://www.youtube.com/embed/DBzEB2QUYaY 111 2026-10-05T07:11:19+00:00 yes https://xdme.com/watch-book21-q024.html https://xdme.com/book21-thumbs/page-024.jpg How Do Factories Make Magnets? Magnets are made in factories, and the recipe starts with metal. Workers pour, press, and shape the metal into the form they want. Then comes the most important step. https://socialmedia.xdme.com/tony/videos-book21/page-024.mp4 https://www.youtube.com/embed/xqw5HHmB52Q 118 2026-10-05T07:14:22+00:00 yes https://xdme.com/watch-book21-q025.html https://xdme.com/book21-thumbs/page-025.jpg What Happens When You Bring a Magnet Near a Compass? A compass needle is a small magnet that can spin freely. It points along the strongest magnetic field nearby. A compass needle is a tiny magnet. https://socialmedia.xdme.com/tony/videos-book21/page-025.mp4 https://www.youtube.com/embed/bQtFlfsyw5c 113 2026-10-05T07:17:24+00:00 yes https://xdme.com/watch-book21-q026.html https://xdme.com/book21-thumbs/page-026.jpg Is All Stainless Steel Magnetic? Is stainless steel always magnetic? No! Stainless steel is iron mixed with chromium and sometimes nickel. Recyclers use magnets to help sort different types of steel. https://socialmedia.xdme.com/tony/videos-book21/page-026.mp4 https://www.youtube.com/embed/WPSDy5sczIU 119 2026-10-05T07:21:07+00:00 yes https://xdme.com/watch-book21-q027.html https://xdme.com/book21-thumbs/page-027.jpg Why Do Magnets Stick to Some Coins but Not Others? Take a magnet and test a handful of coins, and you may get a surprise. Some coins stick, some do not, and some stick just a little. The secret is in what the coin is made of. https://socialmedia.xdme.com/tony/videos-book21/page-027.mp4 https://www.youtube.com/embed/7mYy_t8FeUQ 117 2026-10-05T07:24:10+00:00 yes https://xdme.com/watch-book21-q028.html https://xdme.com/book21-thumbs/page-028.jpg What Is Lodestone, the Natural Magnet? Long ago, people found strange rocks in the ground that could attract iron. We call them lodestones, and they are natural magnets. https://socialmedia.xdme.com/tony/videos-book21/page-028.mp4 https://www.youtube.com/embed/y-GXUJvZFd0 117 2026-10-05T07:27:13+00:00 yes https://xdme.com/watch-book21-q029.html https://xdme.com/book21-thumbs/page-029.jpg Why Won’t Magnets Stick to Wood, Glass, or Plastic? Magnets are picky. They stick to only a few kinds of materials. Wood, glass, and plastic are not on the list. Only iron, nickel, and cobalt respond strongly. https://socialmedia.xdme.com/tony/videos-book21/page-029.mp4 https://www.youtube.com/embed/GKC8sXmtXPU 117 2026-10-05T07:30:46+00:00 yes https://xdme.com/watch-book21-q030.html https://xdme.com/book21-thumbs/page-030.jpg Why Do Magnets Cling to Steel Doors but Not to Walls? Magnets love to cling to a steel fridge door, but they will not cling to a wall. A fridge door usually has a thin steel layer hiding under its paint or plastic. https://socialmedia.xdme.com/tony/videos-book21/page-030.mp4 https://www.youtube.com/embed/aNc7_iDlooY 114 2026-10-05T07:34:08+00:00 yes https://xdme.com/watch-book21-q031.html https://xdme.com/book21-thumbs/page-031.jpg How Can a Magnet Tell a Steel Can From an Aluminum Can? A magnet can sort cans without even looking at them. Food cans are usually steel, and many soda cans are aluminum. A magnet can lift tons of steel at a recycling plant. https://socialmedia.xdme.com/tony/videos-book21/page-031.mp4 https://www.youtube.com/embed/4AWtFTAiw4U 110 2026-10-05T07:37:11+00:00 yes https://xdme.com/watch-book21-q032.html https://xdme.com/book21-thumbs/page-032.jpg Why Can a Magnet Pull Black Grains Out of Beach Sand? Walk along some beaches and you might spot dark streaks in the sand. Those streaks hide tiny black grains that a magnet can pull right out. https://socialmedia.xdme.com/tony/videos-book21/page-032.mp4 https://www.youtube.com/embed/ic-Yz-SVUA0 112 2026-10-05T07:40:13+00:00 yes https://xdme.com/watch-book21-q033.html https://xdme.com/book21-thumbs/page-033.jpg Is There Really Iron in Breakfast Cereal? Many breakfast cereals are fortified, which means iron was added to them. The iron helps people stay healthy, and it is mixed in as a fine metal powder. https://socialmedia.xdme.com/tony/videos-book21/page-033.mp4 https://www.youtube.com/embed/9ceT4veViT4 110 2026-10-05T07:43:16+00:00 yes https://xdme.com/watch-book21-q034.html https://xdme.com/book21-thumbs/page-034.jpg Is Rust Magnetic? Is rust magnetic? Ordinary rust is a reddish iron oxide, and it is only very weakly magnetic. A magnet can still stick to a rusty nail, though. https://socialmedia.xdme.com/tony/videos-book21/page-034.mp4 https://www.youtube.com/embed/9H4mZYMBZTo 112 2026-10-05T07:46:50+00:00 yes https://xdme.com/watch-book21-q035.html https://xdme.com/book21-thumbs/page-035.jpg What Is Ferrofluid, the Liquid That Grows Spikes? Ferrofluid is a strange liquid that grows spikes when a magnet comes near. It is full of magnetic particles so tiny that they float like dust in sunlight. https://socialmedia.xdme.com/tony/videos-book21/page-035.mp4 https://www.youtube.com/embed/EXXySQD1NpI 114 2026-10-05T07:50:05+00:00 yes https://xdme.com/watch-book21-q036.html https://xdme.com/book21-thumbs/page-036.jpg Why Does a Magnet Stop Working When It Gets Very Hot? Heat can make a strong magnet stop working. When atoms get hot, they jiggle faster and faster. This one is for learning about only, never for trying at home! https://socialmedia.xdme.com/tony/videos-book21/page-036.mp4 https://www.youtube.com/embed/ZpL_wXGesy8 122 2026-10-05T07:52:37+00:00 yes https://xdme.com/watch-book21-q037.html https://xdme.com/book21-thumbs/page-037.jpg Can Anything Block a Magnetic Field? Is there any way to block a magnetic field? Nothing blocks it completely, but some materials can redirect it. Engineers use that trick to protect delicate equipment, like very sens https://socialmedia.xdme.com/tony/videos-book21/page-037.mp4 https://www.youtube.com/embed/LR3Pe3NdYqE 118 2026-10-05T07:56:12+00:00 yes https://xdme.com/watch-book21-q038.html https://xdme.com/book21-thumbs/page-038.jpg Why Do Flexible Fridge Magnets Have Stripes? Flexible fridge magnets have a secret hidden inside them. They are made of rubber mixed with magnetic powder, and they are magnetized in thin stripes. https://socialmedia.xdme.com/tony/videos-book21/page-038.mp4 https://www.youtube.com/embed/aj5uAg0zBVw 114 2026-10-05T07:59:13+00:00 yes https://xdme.com/watch-book21-q039.html https://xdme.com/book21-thumbs/page-039.jpg Is Everything a Little Bit Magnetic? Is everything a little bit magnetic? In a way, yes! Everything reacts to a very strong magnetic field, even a pencil, a banana, or you, just a tiny bit. https://socialmedia.xdme.com/tony/videos-book21/page-039.mp4 https://www.youtube.com/embed/g6iEZSLWN78 113 2026-10-05T08:02:16+00:00 yes https://xdme.com/watch-book21-q040.html https://xdme.com/book21-thumbs/page-040.jpg How Do Click-Together Magnetic Building Tiles Work? Click-together magnetic tiles snap into shapes and come apart with a flip. Hidden inside each tile are small magnets, set in a pattern. https://socialmedia.xdme.com/tony/videos-book21/page-040.mp4 https://www.youtube.com/embed/3lHBa_3M3A4 114 2026-10-05T08:05:17+00:00 yes https://xdme.com/watch-book21-q041.html https://xdme.com/book21-thumbs/page-041.jpg How Do Magnetic Drawing Boards Work? A magnetic drawing board lets you draw a picture and erase it with one swipe. It looks like magic, but it is really a clever trick with magnets and tiny cells of powder. https://socialmedia.xdme.com/tony/videos-book21/page-041.mp4 https://www.youtube.com/embed/9_VZz5LIL2Y 109 2026-10-05T08:08:21+00:00 yes https://xdme.com/watch-book21-q042.html https://xdme.com/book21-thumbs/page-042.jpg How Does Magnetic Putty Swallow a Magnet? Magnetic putty seems to gobble up a magnet, like a very slow monster. It is a stretchy putty that is mixed with fine iron powder. Magnetic putty flows like a very thick liquid. https://socialmedia.xdme.com/tony/videos-book21/page-042.mp4 https://www.youtube.com/embed/mRgHnrV2Lj4 110 2026-10-05T08:10:51+00:00 yes https://xdme.com/watch-book21-q043.html https://xdme.com/book21-thumbs/page-043.jpg How Can You Find the Poles of a Magnet That Has No Label? Imagine you find a magnet with no label at all, and you need to know which end is north. A compass can solve the mystery. A compass is a handy pole detector. https://socialmedia.xdme.com/tony/videos-book21/page-043.mp4 https://www.youtube.com/embed/-8jmFtEsKF8 109 2026-10-05T08:13:53+00:00 yes https://xdme.com/watch-book21-q044.html https://xdme.com/book21-thumbs/page-044.jpg Why Does a Magnet Stick Harder to Thick Steel than to Thin Steel? A magnet sticks harder to a thick piece of steel than to a thin one. It all comes down to how much magnetic field the steel can carry. https://socialmedia.xdme.com/tony/videos-book21/page-044.mp4 https://www.youtube.com/embed/TGVDB4vvGdw 106 2026-10-05T08:16:55+00:00 yes https://xdme.com/watch-book21-q045.html https://xdme.com/book21-thumbs/page-045.jpg How Can a Magnet Make a Paper Clip Hover in the Air? Can a paper clip hover in the air, held up by an invisible pull? Yes, with a thread, a magnet, and a little patience. The magnet's field passes through the air and the card. https://socialmedia.xdme.com/tony/videos-book21/page-045.mp4 https://www.youtube.com/embed/bdev1CGdVA8 105 2026-10-05T08:20:28+00:00 yes https://xdme.com/watch-book21-q046.html https://xdme.com/book21-thumbs/page-046.jpg Can Magnets Help Find Rocks That Fell From Space? Some rocks fall from space, and they are called meteorites. Many of them contain iron and nickel, which means a magnet may help find them. Let's go on a meteorite hunt, and find ou https://socialmedia.xdme.com/tony/videos-book21/page-046.mp4 https://www.youtube.com/embed/FsBH_1rZ2Tw 114 2026-10-05T08:23:31+00:00 yes https://xdme.com/watch-book21-q047.html https://xdme.com/book21-thumbs/page-047.jpg How Does a Magnet Sweeper Pick Up Scattered Nails? Imagine a workshop floor covered in sharp nails, tacks, and screws. A magnet sweeper can clean it up, with no pricked fingers at all. https://socialmedia.xdme.com/tony/videos-book21/page-047.mp4 https://www.youtube.com/embed/RD_0AMHi9ZA 107 2026-10-05T08:26:33+00:00 yes https://xdme.com/watch-book21-q048.html https://xdme.com/book21-thumbs/page-048.jpg Why Do Some Fridge Magnets Slide Down the Door? Have you ever seen a fridge magnet slowly slide down the door? A fridge magnet pulls straight into the door, but gravity pulls it straight down. https://socialmedia.xdme.com/tony/videos-book21/page-048.mp4 https://www.youtube.com/embed/pU7ABqIVsBM 108 2026-10-05T08:29:35+00:00 yes https://xdme.com/watch-book21-q049.html https://xdme.com/book21-thumbs/page-049.jpg Why Do Magnets Ignore Real Gold and Silver? Gold and silver are beautiful, but magnets just ignore them. These shiny metals are not magnetic at all. Pure iron is much more magnetic than any common jewelry metal. https://socialmedia.xdme.com/tony/videos-book21/page-049.mp4 https://www.youtube.com/embed/TMqwrTXdbMs 116 2026-10-05T08:33:09+00:00 yes https://xdme.com/watch-book21-q050.html https://xdme.com/book21-thumbs/page-050.jpg How Can You Sort a Mystery Pile of Objects with Only a Magnet? You have a mystery pile of small objects, and only a magnet to sort them. A magnet is a great tool for splitting any pile into two groups. https://socialmedia.xdme.com/tony/videos-book21/page-050.mp4 https://www.youtube.com/embed/nKe7v08ClG4 113 2026-10-05T08:35:40+00:00 yes https://xdme.com/watch-book21-q051.html https://xdme.com/book21-thumbs/page-051.jpg Why Is Earth Like a Giant Bar Magnet? Earth has a magnetic field that looks a lot like the field around a giant bar magnet. It has a north end and a south end, and it reaches every place on the planet. But there is no https://socialmedia.xdme.com/tony/videos-book21/page-051.mp4 https://www.youtube.com/embed/Gv3M0VVoHi8 114 2026-10-05T08:38:43+00:00 yes https://xdme.com/watch-book21-q052.html https://xdme.com/book21-thumbs/page-052.jpg How Does Swirling Liquid Metal Deep Inside Earth Make a Magnet? Deep under your feet, a layer of melted metal swirls around and around. That swirling is what makes Earth's magnetic field. The outer core is about 1,400 miles thick. https://socialmedia.xdme.com/tony/videos-book21/page-052.mp4 https://www.youtube.com/embed/r_x5u8w3ah4 118 2026-10-05T08:42:15+00:00 yes https://xdme.com/watch-book21-q053.html https://xdme.com/book21-thumbs/page-053.jpg Why Does Earth’s Inner Core Stay Solid Even Though It Is So Hot? At the very center of Earth sits a ball of iron and nickel as hot as the surface of the Sun. Even so, it is solid! The inner core is a little smaller than the Moon. https://socialmedia.xdme.com/tony/videos-book21/page-053.mp4 https://www.youtube.com/embed/-lEqRdcKC7s 109 2026-10-05T08:45:00+00:00 yes https://xdme.com/watch-book21-q054.html https://xdme.com/book21-thumbs/page-054.jpg What Does the Magnetic Shield Around Our Planet Do? Our planet has an invisible shield wrapped all around it. It is Earth's magnetic field, and it protects us from a stream of particles flying out from the Sun. https://socialmedia.xdme.com/tony/videos-book21/page-054.mp4 https://www.youtube.com/embed/z_9shYJsiKw 112 2026-10-05T08:48:03+00:00 yes https://xdme.com/watch-book21-q055.html https://xdme.com/book21-thumbs/page-055.jpg What Happens When the Solar Wind Hits Earth’s Magnetic Shield? The Sun is always blowing a wind of tiny charged particles out into space. It is called the solar wind, and it blasts past Earth all the time. https://socialmedia.xdme.com/tony/videos-book21/page-055.mp4 https://www.youtube.com/embed/4W3aELsQJp4 110 2026-10-05T08:51:23+00:00 yes https://xdme.com/watch-book21-q056.html https://xdme.com/book21-thumbs/page-056.jpg What Is the Magnetosphere? Earth's magnetic field does more than point your compass north. It builds a huge bubble in space, and our planet sits right in the middle. https://socialmedia.xdme.com/tony/videos-book21/page-056.mp4 https://www.youtube.com/embed/gymW8S-KQLY 113 2026-10-05T08:54:38+00:00 yes https://xdme.com/watch-book21-q057.html https://xdme.com/book21-thumbs/page-057.jpg Why Is Earth’s Magnetic Bubble Shaped Like a Comet? Earth's magnetic bubble is not round like a ball. It is squeezed on one side and stretched on the other, a bit like a comet. The night-side tail can reach hundreds of thousands of https://socialmedia.xdme.com/tony/videos-book21/page-057.mp4 https://www.youtube.com/embed/QLo9WCFEIms 107 2026-10-05T08:57:10+00:00 yes https://xdme.com/watch-book21-q058.html https://xdme.com/book21-thumbs/page-058.jpg Why Do Magnetic North and True North Point Different Ways? A compass needle does not point exactly to the North Pole. It points toward a different spot, called magnetic north. Maps for hikers often show the local declination. https://socialmedia.xdme.com/tony/videos-book21/page-058.mp4 https://www.youtube.com/embed/nlQvnib7dMk 115 2026-10-05T09:00:45+00:00 yes https://xdme.com/watch-book21-q059.html https://xdme.com/book21-thumbs/page-059.jpg Is the Magnetic North Pole Really Moving? Earth's magnetic north pole is not staying still. It wanders across the Arctic year after year. The pole moved fastest in the early 2000s. https://socialmedia.xdme.com/tony/videos-book21/page-059.mp4 https://www.youtube.com/embed/zAy9j4BDRdQ 118 2026-10-05T09:03:48+00:00 yes https://xdme.com/watch-book21-q060.html https://xdme.com/book21-thumbs/page-060.jpg Which Scientists Track the Pole as It Travels? Because the magnetic poles keep moving, someone has to keep track of them. Teams of scientists around the world do exactly that. Let's meet these pole trackers, who work on the gro https://socialmedia.xdme.com/tony/videos-book21/page-060.mp4 https://www.youtube.com/embed/7prO6X4NyHA 118 2026-10-05T09:06:49+00:00 yes https://xdme.com/watch-book21-q061.html https://xdme.com/book21-thumbs/page-061.jpg Did the North and South Magnetic Poles Ever Swap Places? Here is a surprising fact: Earth's north and south magnetic poles have swapped places before! Rocks tell us it has happened hundreds of times in the past, though at irregular times https://socialmedia.xdme.com/tony/videos-book21/page-061.mp4 https://www.youtube.com/embed/BLZCxfe_yZw 117 2026-10-05T09:09:53+00:00 yes https://xdme.com/watch-book21-q062.html https://xdme.com/book21-thumbs/page-062.jpg How Do Cooled Lava Rocks Keep a Record of the Old Field? Rocks can remember! When lava cools, tiny magnetic grains in it line up with Earth's field at that moment. These rocks are nicknamed fossil compasses. https://socialmedia.xdme.com/tony/videos-book21/page-062.mp4 https://www.youtube.com/embed/iiRlXIGhyLk 111 2026-10-05T09:12:56+00:00 yes https://xdme.com/watch-book21-q063.html https://xdme.com/book21-thumbs/page-063.jpg What Tools Measure the Pull of Earth’s Magnet? How do scientists measure the pull of Earth's magnet? They use special sensors called magnetometers. You even have one in your pocket, if you own a phone! https://socialmedia.xdme.com/tony/videos-book21/page-063.mp4 https://www.youtube.com/embed/3JiaOeTlkMU 114 2026-10-05T09:15:58+00:00 yes https://xdme.com/watch-book21-q064.html https://xdme.com/book21-thumbs/page-064.jpg Why Is There a Weak Spot Over the South Atlantic Ocean? Earth's magnetic field is strong in some places and weak in others. Over South America and the South Atlantic Ocean, it is weaker than almost anywhere else. https://socialmedia.xdme.com/tony/videos-book21/page-064.mp4 https://www.youtube.com/embed/YwvS57qBfgs 113 2026-10-05T09:19:16+00:00 yes https://xdme.com/watch-book21-q065.html https://xdme.com/book21-thumbs/page-065.jpg What Would Life Be Like If Earth’s Shield Vanished? Imagine waking up one morning, and Earth's magnetic shield was gone. What would happen to life on Earth? Let's think it through, step by step, like real scientists do. https://socialmedia.xdme.com/tony/videos-book21/page-065.mp4 https://www.youtube.com/embed/1iEWs0-zhco 111 2026-10-05T09:22:20+00:00 yes https://xdme.com/watch-book21-q066.html https://xdme.com/book21-thumbs/page-066.jpg Why Did Mars Lose Its Magnetic Field? Mars once had a magnetic field, a bit like Earth's. Today it is gone. Old magnetism is still locked in some Mars rocks. Mars is small, so it cooled faster than Earth. https://socialmedia.xdme.com/tony/videos-book21/page-066.mp4 https://www.youtube.com/embed/IkoMlSfNHcs 110 2026-10-05T09:25:26+00:00 yes https://xdme.com/watch-book21-q067.html https://xdme.com/book21-thumbs/page-067.jpg Do Other Planets Have Magnetic Fields? Does Earth have the only magnetic field in space? Not at all! Many planets have magnetic fields, and some are very strange. Ganymede, a moon of Jupiter, has its own magnetic field. https://socialmedia.xdme.com/tony/videos-book21/page-067.mp4 https://www.youtube.com/embed/vQCLUqp4PLs 118 2026-10-05T09:28:58+00:00 yes https://xdme.com/watch-book21-q068.html https://xdme.com/book21-thumbs/page-068.jpg Why Does Jupiter Have Such a Huge Magnetic Field? Jupiter has the most powerful magnetic field of any planet. Its magnetic bubble is so huge that, if we could see it from Earth, it would look bigger than the full Moon! https://socialmedia.xdme.com/tony/videos-book21/page-068.mp4 https://www.youtube.com/embed/_3Q0hD5EA2I 116 2026-10-05T09:32:03+00:00 yes https://xdme.com/watch-book21-q069.html https://xdme.com/book21-thumbs/page-069.jpg Why Do Scientists Call the Sun a Giant Magnet? We usually think of the Sun as a ball of fire and light. Scientists also call it a giant magnet! And remember, never look at the Sun directly, because it can hurt your eyes. https://socialmedia.xdme.com/tony/videos-book21/page-069.mp4 https://www.youtube.com/embed/6SlkDR6Quf4 110 2026-10-05T09:35:04+00:00 yes https://xdme.com/watch-book21-q070.html https://xdme.com/book21-thumbs/page-070.jpg What Are Sunspots, and What Do Magnets Have to Do with Them? Some days, the Sun has dark patches on its surface called sunspots. They look like tiny freckles, but some are bigger than Earth! Some sunspots are larger than Earth. https://socialmedia.xdme.com/tony/videos-book21/page-070.mp4 https://www.youtube.com/embed/O9XIyIsC0pg 116 2026-10-05T09:38:08+00:00 yes https://xdme.com/watch-book21-q071.html https://xdme.com/book21-thumbs/page-071.jpg Why Do Compass Needles Wiggle During a Magnetic Storm? Sometimes the Sun throws out a giant burst of charged particles. When they hit Earth's magnetic field, they shake it, and that can make a compass needle wiggle. https://socialmedia.xdme.com/tony/videos-book21/page-071.mp4 https://www.youtube.com/embed/vDECP-FsuzM 111 2026-10-05T09:41:12+00:00 yes https://xdme.com/watch-book21-q072.html https://xdme.com/book21-thumbs/page-072.jpg Is Earth’s Magnet Stronger than a Fridge Magnet? Which is stronger, the magnet in your hand or the magnet under your feet? The answer is a surprise. Earth's field is much weaker than a fridge magnet's, but it is also much, much b https://socialmedia.xdme.com/tony/videos-book21/page-072.mp4 https://www.youtube.com/embed/vO_A3tMipBk 110 2026-10-05T09:44:14+00:00 yes https://xdme.com/watch-book21-q073.html https://xdme.com/book21-thumbs/page-073.jpg Could Astronauts Use a Compass on the Moon? Imagine walking on the Moon with a compass in your hand. Which way would the needle point? The answer might surprise you! Spacecraft found weak patches of magnetism on the Moon's s https://socialmedia.xdme.com/tony/videos-book21/page-073.mp4 https://www.youtube.com/embed/klnzZL2i_uU 107 2026-10-05T09:47:21+00:00 yes https://xdme.com/watch-book21-q074.html https://xdme.com/book21-thumbs/page-074.jpg Why Does a Hanging Magnet Tilt Downward Near the Poles? Earth's magnetic field lines do not just run across the ground. Near the poles, they dive straight down into the planet! Compass makers build different compasses for different part https://socialmedia.xdme.com/tony/videos-book21/page-074.mp4 https://www.youtube.com/embed/lAGfAaKLSrc 108 2026-10-05T09:50:34+00:00 yes https://xdme.com/watch-book21-q075.html https://xdme.com/book21-thumbs/page-075.jpg Is Earth’s Magnetism the Same Strength Everywhere? Earth's magnetic field is not the same strength everywhere you go. It is stronger in some places and weaker in others. Northern Canada's field is much stronger than the equator's. https://socialmedia.xdme.com/tony/videos-book21/page-075.mp4 https://www.youtube.com/embed/56nk8sa-UhA 114 2026-10-05T09:53:37+00:00 yes https://xdme.com/watch-book21-q076.html https://xdme.com/book21-thumbs/page-076.jpg How Did People First Discover the Compass? The compass is one of the greatest tools ever invented. But nobody knows the exact day it was discovered. Here is the story of how people probably found it. https://socialmedia.xdme.com/tony/videos-book21/page-076.mp4 https://www.youtube.com/embed/jqZkioMVRb4 112 2026-10-05T06:11:23+00:00 yes https://xdme.com/watch-book21-q077.html https://xdme.com/book21-thumbs/page-077.jpg What Do the Letters and Numbers on a Compass Mean? A compass is covered with letters and numbers. They are not decorations, they are a secret code for finding your way. Let's crack the code and learn to read the dial like a real ex https://socialmedia.xdme.com/tony/videos-book21/page-077.mp4 https://www.youtube.com/embed/8GAJv4bC-gE 118 2026-10-05T06:11:24+00:00 yes https://xdme.com/watch-book21-q078.html https://xdme.com/book21-thumbs/page-078.jpg Why Is the Needle in Many Compasses Floating in Liquid? Look closely at many compasses, and you will see something strange. The needle floats in a clear liquid! The liquid inside a compass is usually a clear oil or alcohol. https://socialmedia.xdme.com/tony/videos-book21/page-078.mp4 https://www.youtube.com/embed/GfqmkVTTDl8 107 2026-10-05T06:11:26+00:00 yes https://xdme.com/watch-book21-q079.html https://xdme.com/book21-thumbs/page-079.jpg How Can You Walk in a Straight Line Using a Compass? Have you ever tried to walk in a straight line without a path? It is much harder than you think! A compass can help you stay on track. https://socialmedia.xdme.com/tony/videos-book21/page-079.mp4 https://www.youtube.com/embed/TTuFnPH5Vvo 104 2026-10-05T06:11:32+00:00 yes https://xdme.com/watch-book21-q080.html https://xdme.com/book21-thumbs/page-080.jpg What Can Fool a Compass? A compass seems simple, but lots of things can fool it. Anything magnetic, or any electric current nearby, can pull on a compass needle. https://socialmedia.xdme.com/tony/videos-book21/page-080.mp4 https://www.youtube.com/embed/2ZfTnnah354 109 2026-10-05T06:12:05+00:00 yes https://xdme.com/watch-book21-q081.html https://xdme.com/book21-thumbs/page-081.jpg How Can You Build a Simple Compass at Home? You can build your very own compass at home with just a few simple things. All you need is a steel pin or paper clip, a magnet, and a bowl of water. Let's build one together, with https://socialmedia.xdme.com/tony/videos-book21/page-081.mp4 https://www.youtube.com/embed/Oa-cDjCXgpE 110 2026-10-05T06:14:41+00:00 yes https://xdme.com/watch-book21-q082.html https://xdme.com/book21-thumbs/page-082.jpg Do Compasses Work the Same in the Southern Hemisphere? Does a compass work the same way in the Southern Hemisphere? Yes, it still points toward magnetic north! But there is a tricky detail that compass makers have to think about. https://socialmedia.xdme.com/tony/videos-book21/page-082.mp4 https://www.youtube.com/embed/K5ODdWGJxok 107 2026-10-05T06:20:16+00:00 yes https://xdme.com/watch-book21-q083.html https://xdme.com/book21-thumbs/page-083.jpg How Did Sailors Steer Before GPS? Long ago, sailors crossed whole oceans without GPS. They did it by combining many simple tools, and a lot of careful thinking. There were no satellites, no screens, and no maps on https://socialmedia.xdme.com/tony/videos-book21/page-083.mp4 https://www.youtube.com/embed/ZPzmgE9Rwwk 117 2026-10-05T06:24:19+00:00 yes https://xdme.com/watch-book21-q084.html https://xdme.com/book21-thumbs/page-084.jpg Why Do Iron Ships Need Compass Corrections? Big iron and steel ships have a problem with compasses. The ship itself becomes a little magnetic, and that fools the needle! A compass can get confused by the very ship it is sitt https://socialmedia.xdme.com/tony/videos-book21/page-084.mp4 https://www.youtube.com/embed/DcnA1qqrCEY 110 2026-10-05T06:27:21+00:00 yes https://xdme.com/watch-book21-q085.html https://xdme.com/book21-thumbs/page-085.jpg How Does a Gyrocompass Find North Without a Magnet? Is there a compass that works without any magnet at all? Yes! It is called a gyrocompass. A spinning bicycle wheel is also hard to tilt, for the same reason. https://socialmedia.xdme.com/tony/videos-book21/page-085.mp4 https://www.youtube.com/embed/l8XD62OZmXE 115 2026-10-05T06:30:24+00:00 yes https://xdme.com/watch-book21-q086.html https://xdme.com/book21-thumbs/page-086.jpg Why Do We Still Need Compasses When We Have GPS? GPS is amazing, but it does not always work. So smart hikers still carry a compass. A compass can still work when a phone battery is dead. https://socialmedia.xdme.com/tony/videos-book21/page-086.mp4 https://www.youtube.com/embed/ImlFHMgKScQ 109 2026-10-05T06:33:58+00:00 yes https://xdme.com/watch-book21-q087.html https://xdme.com/book21-thumbs/page-087.jpg What Is Orienteering? Imagine a race where your map and compass matter as much as your legs. That is orienteering! Orienteering courses come in many levels, from easy beginner paths to expert ones. https://socialmedia.xdme.com/tony/videos-book21/page-087.mp4 https://www.youtube.com/embed/S6deROGUqGI 108 2026-10-05T06:37:00+00:00 yes https://xdme.com/watch-book21-q088.html https://xdme.com/book21-thumbs/page-088.jpg Why Does a Phone Ask You to Draw a Figure Eight to Fix Its Compass? Sometimes a phone asks you to wave it in a figure eight to fix its compass. It might seem like a silly dance. But it is really clever science, and here is why. https://socialmedia.xdme.com/tony/videos-book21/page-088.mp4 https://www.youtube.com/embed/GGK8O03-6So 108 2026-10-05T06:40:03+00:00 yes https://xdme.com/watch-book21-q089.html https://xdme.com/book21-thumbs/page-089.jpg Can a Compass Work Underwater? Can a compass really work underwater? It sounds tricky, because water changes so many things. But magnets and water get along just fine! https://socialmedia.xdme.com/tony/videos-book21/page-089.mp4 https://www.youtube.com/embed/yJw5olTPzJ0 114 2026-10-05T06:43:06+00:00 yes https://xdme.com/watch-book21-q090.html https://xdme.com/book21-thumbs/page-090.jpg What Is a Compass Rose on a Map? Look at a map, and you may see a pretty little star or flower in one corner. That is a compass rose! The points look like petals, which gives the rose its name. https://socialmedia.xdme.com/tony/videos-book21/page-090.mp4 https://www.youtube.com/embed/rABPuxM_2g4 111 2026-10-05T06:46:08+00:00 yes https://xdme.com/watch-book21-q091.html https://xdme.com/book21-thumbs/page-091.jpg How Do Pilots Use Compass Headings, and Why Do Runways Have Numbers? When pilots fly, they need to know exactly which way to go. They use compass headings, and airports even put those numbers on the runways! https://socialmedia.xdme.com/tony/videos-book21/page-091.mp4 https://www.youtube.com/embed/3fVurRX86DE 117 2026-10-05T06:49:41+00:00 yes https://xdme.com/watch-book21-q092.html https://xdme.com/book21-thumbs/page-092.jpg How Do People Find Their Way in the Arctic When Compasses Wobble? The Arctic is a land of ice and snow, and it is also close to the magnetic north pole. That makes a regular compass act strangely. https://socialmedia.xdme.com/tony/videos-book21/page-092.mp4 https://www.youtube.com/embed/nHuOkCG3OUY 115 2026-10-05T06:52:43+00:00 yes https://xdme.com/watch-book21-q093.html https://xdme.com/book21-thumbs/page-093.jpg Does Moss Really Grow Only on the North Side of Trees? You might have heard that moss grows only on the north side of trees. Is it true? Let's put on our science hats and find out, and see what a real explorer should trust. https://socialmedia.xdme.com/tony/videos-book21/page-093.mp4 https://www.youtube.com/embed/c6bNU0Jigz0 109 2026-10-05T06:55:16+00:00 yes https://xdme.com/watch-book21-q094.html https://xdme.com/book21-thumbs/page-094.jpg How Did Pacific Wayfinders Cross Oceans Without a Compass? Thousands of years ago, brave sailors crossed huge oceans in canoes. They had no compasses, and no maps, and yet they found tiny islands in the Pacific. https://socialmedia.xdme.com/tony/videos-book21/page-094.mp4 https://www.youtube.com/embed/yIRWf7Lyvww 118 2026-10-05T06:58:49+00:00 yes https://xdme.com/watch-book21-q095.html https://xdme.com/book21-thumbs/page-095.jpg Why Do Most Maps Put North at the Top? Look at almost any map, and north is at the top. But there is no law of nature that says it has to be! The word orient comes from the old habit of putting east at the top. https://socialmedia.xdme.com/tony/videos-book21/page-095.mp4 https://www.youtube.com/embed/AGeKPLMAlCw 106 2026-10-05T07:01:51+00:00 yes https://xdme.com/watch-book21-q096.html https://xdme.com/book21-thumbs/page-096.jpg What Should You Do If You Get Lost on a Trail? Getting lost on a trail can feel scary. But if you know the right steps, you can stay safe. Let's learn what to do, and then practice with a grown-up. https://socialmedia.xdme.com/tony/videos-book21/page-096.mp4 https://www.youtube.com/embed/7jwjBZUAXdE 106 2026-10-05T07:05:03+00:00 yes https://xdme.com/watch-book21-q097.html https://xdme.com/book21-thumbs/page-097.jpg How Can a Watch and the Sun Show You Which Way Is South? Here is a cool trick for finding south with nothing but a watch and the Sun. It works in the Northern Hemisphere with an old-style watch that has hands. Let's learn how. https://socialmedia.xdme.com/tony/videos-book21/page-097.mp4 https://www.youtube.com/embed/2QRjKcftdaE 109 2026-10-05T07:09:17+00:00 yes https://xdme.com/watch-book21-q098.html https://xdme.com/book21-thumbs/page-098.jpg What Is Dead Reckoning? Imagine you are lost at sea, with no GPS and no landmarks anywhere. How could you figure out where you are? Navigators use a clever method called dead reckoning. https://socialmedia.xdme.com/tony/videos-book21/page-098.mp4 https://www.youtube.com/embed/yuXjmLosVcY 108 2026-10-05T07:11:20+00:00 yes https://xdme.com/watch-book21-q099.html https://xdme.com/book21-thumbs/page-099.jpg How Do Geocachers Use Coordinates to Find Hidden Treasure? Imagine a treasure hunt where the treasure is hidden somewhere in the real world. It is called geocaching, and people play it all over the globe. https://socialmedia.xdme.com/tony/videos-book21/page-099.mp4 https://www.youtube.com/embed/trPKa9GZplw 115 2026-10-05T07:14:23+00:00 yes https://xdme.com/watch-book21-q100.html https://xdme.com/book21-thumbs/page-100.jpg How Can Sunrise and Sunset Help You Find Directions? The Sun can be a natural compass. It rises in one place and sets in another. In summer in Canada, the Sun rises well north of east. https://socialmedia.xdme.com/tony/videos-book21/page-100.mp4 https://www.youtube.com/embed/C9K84vvQCKQ 111 2026-10-05T07:17:56+00:00 yes https://xdme.com/watch-book21-q101.html https://xdme.com/book21-thumbs/page-101.jpg How Does a Fridge Door Stay Sealed Without a Latch? Have you ever noticed that a fridge door closes tight without any latch or lock? The secret is a magnet hidden in the rubber seal around the edge. https://socialmedia.xdme.com/tony/videos-book21/page-101.mp4 https://www.youtube.com/embed/MlA_pOL7OKk 109 2026-10-05T07:21:08+00:00 yes https://xdme.com/watch-book21-q102.html https://xdme.com/book21-thumbs/page-102.jpg How Do Cabinet Doors Click Shut with Magnets? Push a cabinet door almost closed, and it clicks shut all by itself. There is no spring, no hook, and no latch. Just a small magnet and a bit of steel working together! https://socialmedia.xdme.com/tony/videos-book21/page-102.mp4 https://www.youtube.com/embed/E7qj5Ga3SV8 104 2026-10-05T07:23:39+00:00 yes https://xdme.com/watch-book21-q103.html https://xdme.com/book21-thumbs/page-103.jpg How Does an Electromagnet Switch on and Off? Imagine a magnet you can switch on and off, like a light. It is called an electromagnet! An electromagnet is often strong enough to lift a car when it is built large enough. https://socialmedia.xdme.com/tony/videos-book21/page-103.mp4 https://www.youtube.com/embed/tRhoSpJwysE 110 2026-10-05T07:26:42+00:00 yes https://xdme.com/watch-book21-q104.html https://xdme.com/book21-thumbs/page-104.jpg How Does a Giant Magnet Lift Cars and Scrap Steel? At a scrap yard, a giant crane lifts a huge pile of steel with no hooks or ropes around it. It uses a giant electromagnet instead. Nothing is tied on, and nothing is hooked. https://socialmedia.xdme.com/tony/videos-book21/page-104.mp4 https://www.youtube.com/embed/5t6I-fLhjHc 110 2026-10-05T07:30:47+00:00 yes https://xdme.com/watch-book21-q105.html https://xdme.com/book21-thumbs/page-105.jpg How Do Magnets Help an Electric Motor Spin? Inside a fan, a toy car, or even your phone, a small motor is spinning. And magnets are the secret to how it works. A tiny motor in a phone makes it buzz. https://socialmedia.xdme.com/tony/videos-book21/page-105.mp4 https://www.youtube.com/embed/TTSmtVvpU1g 104 2026-10-05T07:34:10+00:00 yes https://xdme.com/watch-book21-q106.html https://xdme.com/book21-thumbs/page-106.jpg How Can Spinning a Magnet Make Electricity? A spinning magnet can make electricity! That is how most of the power that lights your home gets made. A bicycle light often uses a small generator called a dynamo. https://socialmedia.xdme.com/tony/videos-book21/page-106.mp4 https://www.youtube.com/embed/wp677YchL5o 108 2026-10-05T07:37:12+00:00 yes https://xdme.com/watch-book21-q107.html https://xdme.com/book21-thumbs/page-107.jpg Why Must Metal Stay Out of the Room with an Mri Machine? In a hospital, there is a room with a very special rule: no metal allowed! It holds an MRI machine, with one of the strongest magnets people have ever used in a hospital. https://socialmedia.xdme.com/tony/videos-book21/page-107.mp4 https://www.youtube.com/embed/7lIiY5HCreI 110 2026-10-05T07:40:15+00:00 yes https://xdme.com/watch-book21-q108.html https://xdme.com/book21-thumbs/page-108.jpg How Do the Stripes on Some Cards Store Information? Turn over a gift card or a hotel key card, and you might see a dark stripe. It looks like plain brown tape, but it hides a secret code made from tiny magnets. https://socialmedia.xdme.com/tony/videos-book21/page-108.mp4 https://www.youtube.com/embed/n0mpYIbucns 111 2026-10-05T07:43:18+00:00 yes https://xdme.com/watch-book21-q109.html https://xdme.com/book21-thumbs/page-109.jpg How Do Tapes and Hard Drives Store Information with Magnets? Old cassette tapes and computer hard drives look very different. But they share a secret: both store information using tiny magnetic patterns. One saves music, and the other saves https://socialmedia.xdme.com/tony/videos-book21/page-109.mp4 https://www.youtube.com/embed/F9EcCU6P0k4 114 2026-10-05T07:46:51+00:00 yes https://xdme.com/watch-book21-q110.html https://xdme.com/book21-thumbs/page-110.jpg How Does a Magnet Help a Window Alarm Know When It Opens? A window alarm can tell the moment a window opens, even though it has no eyes. The secret is a magnet and a tiny glass switch. Doors use the same trick. A reed switch has no moving https://socialmedia.xdme.com/tony/videos-book21/page-110.mp4 https://www.youtube.com/embed/SJiiuPIKr30 110 2026-10-05T07:49:22+00:00 yes https://xdme.com/watch-book21-q111.html https://xdme.com/book21-thumbs/page-111.jpg How Does a Bike Computer Count Wheel Turns? A bike computer can tell you how fast you are going and how far you have ridden. But it never touches the wheel! The trick is a tiny magnet and a sensor that notice each turn. https://socialmedia.xdme.com/tony/videos-book21/page-111.mp4 https://www.youtube.com/embed/rEmiZvYFtFc 106 2026-10-05T07:52:39+00:00 yes https://xdme.com/watch-book21-q112.html https://xdme.com/book21-thumbs/page-112.jpg How Can a Train Float on Magnets? Imagine a train that floats just above its track, with no wheels touching at all. It is called a maglev train, and it really exists! https://socialmedia.xdme.com/tony/videos-book21/page-112.mp4 https://www.youtube.com/embed/AOClzsmav-I 112 2026-10-05T07:55:40+00:00 yes https://xdme.com/watch-book21-q113.html https://xdme.com/book21-thumbs/page-113.jpg How Can Magnets Slow Down a Roller Coaster Without Touching It? At the end of some roller coasters, the cars slow to a smooth stop without anything touching them. The secret is magnets! The faster the coaster goes, the stronger this magnetic br https://socialmedia.xdme.com/tony/videos-book21/page-113.mp4 https://www.youtube.com/embed/fetb9EfYwLo 112 2026-10-05T07:59:14+00:00 yes https://xdme.com/watch-book21-q114.html https://xdme.com/book21-thumbs/page-114.jpg Why Does a Magnet Fall Slowly Through a Copper Pipe? Drop a magnet through a plastic pipe, and it falls fast. Drop it through a copper pipe, and it falls slowly, as if something invisible is catching it! https://socialmedia.xdme.com/tony/videos-book21/page-114.mp4 https://www.youtube.com/embed/z1cnSCKQVhM 109 2026-10-05T08:02:16+00:00 yes https://xdme.com/watch-book21-q115.html https://xdme.com/book21-thumbs/page-115.jpg How Can a Cooktop Heat a Pot Without a Flame? Some stoves can cook your dinner without a single flame. They use an invisible magnetic field to heat the pot. A grown-up should always do the cooking! https://socialmedia.xdme.com/tony/videos-book21/page-115.mp4 https://www.youtube.com/embed/2mRyEGzHggU 111 2026-10-05T08:05:19+00:00 yes https://xdme.com/watch-book21-q116.html https://xdme.com/book21-thumbs/page-116.jpg How Can a Fire Door Stay Open and Still Close by Itself? In some school hallways, heavy fire doors stay wide open all day. But when there is a fire alarm, they swing closed all by themselves! https://socialmedia.xdme.com/tony/videos-book21/page-116.mp4 https://www.youtube.com/embed/kZUd3S4QtcQ 107 2026-10-05T08:07:50+00:00 yes https://xdme.com/watch-book21-q117.html https://xdme.com/book21-thumbs/page-117.jpg How Can a Lamp or Globe Float Above Its Base? In some shops and homes, a lamp or a globe floats in the air above its base. It seems like magic, but it is really clever engineering. https://socialmedia.xdme.com/tony/videos-book21/page-117.mp4 https://www.youtube.com/embed/cK__BEow3TA 111 2026-10-05T08:10:52+00:00 yes https://xdme.com/watch-book21-q118.html https://xdme.com/book21-thumbs/page-118.jpg How Do Metal Detectors Find Hidden Metal? Metal detectors can find coins, keys, and treasure hidden under sand or soil. They work with an invisible magnetic field. Some detectors can tell different metals apart by how they https://socialmedia.xdme.com/tony/videos-book21/page-118.mp4 https://www.youtube.com/embed/KjqEqqIk91g 114 2026-10-05T08:13:54+00:00 yes https://xdme.com/watch-book21-q119.html https://xdme.com/book21-thumbs/page-119.jpg How Does a Laptop Know When Its Lid Closes? Close your laptop, and the screen turns off at once. Open it, and the laptop wakes up. There is no button to push, so how does it know? https://socialmedia.xdme.com/tony/videos-book21/page-119.mp4 https://www.youtube.com/embed/djhUm9rrncI 103 2026-10-05T08:16:56+00:00 yes https://xdme.com/watch-book21-q120.html https://xdme.com/book21-thumbs/page-120.jpg Why Is Some Money Printed with Magnetic Ink? Some paper money and bank checks have a secret ingredient in their ink: tiny magnetic particles! You cannot see the magnetism, but machines can sense it. https://socialmedia.xdme.com/tony/videos-book21/page-120.mp4 https://www.youtube.com/embed/8ZdciSehH1k 108 2026-10-05T08:20:29+00:00 yes https://xdme.com/watch-book21-q121.html https://xdme.com/book21-thumbs/page-121.jpg How Do Pinball Flippers Flick the Ball? Press the button on a pinball machine, and the flipper snaps up in a flash. Inside, an electromagnet is hard at work, even though you cannot see it. https://socialmedia.xdme.com/tony/videos-book21/page-121.mp4 https://www.youtube.com/embed/0VXzBkr4Nl0 109 2026-10-05T08:23:32+00:00 yes https://xdme.com/watch-book21-q122.html https://xdme.com/book21-thumbs/page-122.jpg How Does an Electric Guitar Turn Plucked Strings Into Sound? An electric guitar does not have a big hollow body to make its sound louder. Instead, it has magnets and thin wire hiding under the strings. https://socialmedia.xdme.com/tony/videos-book21/page-122.mp4 https://www.youtube.com/embed/XZvjHP3jGXI 114 2026-10-05T08:26:34+00:00 yes https://xdme.com/watch-book21-q123.html https://xdme.com/book21-thumbs/page-123.jpg Why Can a Spinning Top Float Above a Magnetic Base? Some toys have a spinning top that floats in the air above a magnetic base. It seems to defy gravity! It looks like a magic trick, but it is real science. https://socialmedia.xdme.com/tony/videos-book21/page-123.mp4 https://www.youtube.com/embed/GL0j2otSSUU 103 2026-10-05T08:29:36+00:00 yes https://xdme.com/watch-book21-q124.html https://xdme.com/book21-thumbs/page-124.jpg How Do Food Factories Catch Stray Bits of Metal? Food factories work hard to keep every bite safe. Sometimes a tiny bit of metal, like a screw end or a wire piece, breaks off a machine. Magnets help to catch those stray bits! https://socialmedia.xdme.com/tony/videos-book21/page-124.mp4 https://www.youtube.com/embed/SWpSevPltQ0 108 2026-10-05T08:32:38+00:00 yes https://xdme.com/watch-book21-q125.html https://xdme.com/book21-thumbs/page-125.jpg How Do Toy Train Cars Link Up with Magnets? Wooden toy trains can link together without any hooks or buckles. The secret is hidden magnets in the ends of each car. Hidden magnets in toys must be sealed in tightly so little o https://socialmedia.xdme.com/tony/videos-book21/page-125.mp4 https://www.youtube.com/embed/cu2ZN2L9ST0 104 2026-10-05T08:35:42+00:00 yes https://xdme.com/watch-book21-q126.html https://xdme.com/book21-thumbs/page-126.jpg How Do Sea Turtles Use Earth’s Magnet to Find Their Way? A baby sea turtle hatches on a beach, swims out to sea, and years later returns to lay its eggs on the very same beach. How does it find its way across a huge ocean? It may use Ear https://socialmedia.xdme.com/tony/videos-book21/page-126.mp4 https://www.youtube.com/embed/b11aayJxjAY 111 2026-10-05T08:38:44+00:00 yes https://xdme.com/watch-book21-q127.html https://xdme.com/book21-thumbs/page-127.jpg Do Birds Really Have a Built-In Compass? Every year, many birds fly thousands of miles to warmer places and then back again. They do not use maps or GPS. Do birds really have a built-in compass? https://socialmedia.xdme.com/tony/videos-book21/page-127.mp4 https://www.youtube.com/embed/boN0OwG2YJg 113 2026-10-05T08:42:20+00:00 yes https://xdme.com/watch-book21-q128.html https://xdme.com/book21-thumbs/page-128.jpg Can Sharks Use a Magnetic Map to Swim Home? Sharks swim across huge oceans and somehow find their way home. Scientists wondered if they might use a magnetic map. Here is how they tested some small sharks to find out! https://socialmedia.xdme.com/tony/videos-book21/page-128.mp4 https://www.youtube.com/embed/8tRD_qzd_Uk 107 2026-10-05T08:45:02+00:00 yes https://xdme.com/watch-book21-q129.html https://xdme.com/book21-thumbs/page-129.jpg How Might Salmon Use Earth’s Magnet to Return to Their Home River? Salmon begin their lives in a small river. They swim out to the ocean for years, and then return to the very same river where they were born. How do they find it? https://socialmedia.xdme.com/tony/videos-book21/page-129.mp4 https://www.youtube.com/embed/PSKxJfCAmPw 114 2026-10-05T08:48:07+00:00 yes https://xdme.com/watch-book21-q130.html https://xdme.com/book21-thumbs/page-130.jpg Do Cows and Deer Really Face North and South? In 2008, some scientists made a surprising claim. They said cows and deer might line up north and south when they graze or rest. Scientists use the word replicate for repeating an https://socialmedia.xdme.com/tony/videos-book21/page-130.mp4 https://www.youtube.com/embed/DYGGNkk0dNk 108 2026-10-05T08:51:35+00:00 yes https://xdme.com/watch-book21-q131.html https://xdme.com/book21-thumbs/page-131.jpg Which Tiny Living Things Carry Their Own Compass Needles? Some of the tiniest living things on Earth carry their own compass needles. They are so small that you need a powerful microscope to see them. Let's meet these magnetic bacteria! https://socialmedia.xdme.com/tony/videos-book21/page-131.mp4 https://www.youtube.com/embed/3zOO876O7as 106 2026-10-05T08:54:07+00:00 yes https://xdme.com/watch-book21-q132.html https://xdme.com/book21-thumbs/page-132.jpg How Do Spiny Lobsters Use a Magnetic Map? Spiny lobsters can crawl a long way across the ocean floor and still find their way home. They do not have eyes that work in the dark depths. Scientists wondered if they use a magn https://socialmedia.xdme.com/tony/videos-book21/page-132.mp4 https://www.youtube.com/embed/quOPBva_Cbc 111 2026-10-05T08:57:41+00:00 yes https://xdme.com/watch-book21-q133.html https://xdme.com/book21-thumbs/page-133.jpg How Do Monarch Butterflies Use a Magnetic Compass? Every fall, monarch butterflies fly thousands of miles to Mexico. Even though they are tiny, they find their way to the very same forests. https://socialmedia.xdme.com/tony/videos-book21/page-133.mp4 https://www.youtube.com/embed/TwmcuZhq2rQ 108 2026-10-05T09:00:13+00:00 yes https://xdme.com/watch-book21-q134.html https://xdme.com/book21-thumbs/page-134.jpg Why Don’t Our Bodies Sense Magnets the Way They Sense Heat? Birds, turtles, and sharks seem to sense magnets. But can you feel a magnet from far away? Humans cannot, and scientists are curious about why. https://socialmedia.xdme.com/tony/videos-book21/page-134.mp4 https://www.youtube.com/embed/36NtVpfdrMs 106 2026-10-05T09:03:17+00:00 yes https://xdme.com/watch-book21-q135.html https://xdme.com/book21-thumbs/page-135.jpg How Do Mole-Rats Use Magnetism Underground? Deep underground, there are animals that live in total darkness. Ansell's mole-rats in Africa live in dark tunnels and have very poor eyesight. How do they know which way to go? https://socialmedia.xdme.com/tony/videos-book21/page-135.mp4 https://www.youtube.com/embed/DngEcmT-a1g 108 2026-10-05T09:06:52+00:00 yes https://xdme.com/watch-book21-q136.html https://xdme.com/book21-thumbs/page-136.jpg How Do Scientists Test Whether an Animal Can Sense Magnetism? How can a scientist find out whether an animal can sense magnetism? The animal cannot tell us, so scientists must be clever. Scientists must keep the experiment free of metal that https://socialmedia.xdme.com/tony/videos-book21/page-136.mp4 https://www.youtube.com/embed/LxvXmg7Rj4o 109 2026-10-05T09:09:55+00:00 yes https://xdme.com/watch-book21-q137.html https://xdme.com/book21-thumbs/page-137.jpg Could Bees or Ants Use Magnetism to Find Their Way? Honeybees and ants are tiny, but they are great at finding their way home. Could magnetism be part of their secret? Bees can also sense the polarized pattern of light in the sky. https://socialmedia.xdme.com/tony/videos-book21/page-137.mp4 https://www.youtube.com/embed/rFHqqRrMOoM 105 2026-10-05T09:12:57+00:00 yes https://xdme.com/watch-book21-q138.html https://xdme.com/book21-thumbs/page-138.jpg What Is a Magnetar? Far out in space, there is a star with the strongest magnetic field anyone has ever found. It is called a magnetar. Magnetars sometimes release huge bursts of energy that astronome https://socialmedia.xdme.com/tony/videos-book21/page-138.mp4 https://www.youtube.com/embed/7HohgYQsUf8 112 2026-10-05T09:16:15+00:00 yes https://xdme.com/watch-book21-q139.html https://xdme.com/book21-thumbs/page-139.jpg Why Do Mars Rovers Carry Magnets? Robots on Mars have carried small magnets, and it was not to stick things on a fridge. They used the magnets to catch dust from the air. https://socialmedia.xdme.com/tony/videos-book21/page-139.mp4 https://www.youtube.com/embed/dlF7VuoeCyo 109 2026-10-05T09:19:18+00:00 yes https://xdme.com/watch-book21-q140.html https://xdme.com/book21-thumbs/page-140.jpg Do Magnets Work on the Space Station? Do magnets still work when you float far above the ground in space? Yes, they do! There is even a giant magnet on the International Space Station. https://socialmedia.xdme.com/tony/videos-book21/page-140.mp4 https://www.youtube.com/embed/xz5j4mKMfno 114 2026-10-05T09:22:21+00:00 yes https://xdme.com/watch-book21-q141.html https://xdme.com/book21-thumbs/page-141.jpg How Do Satellites Use Magnets to Turn Without Fuel? How do you turn a satellite in space, where there is nothing to push against? One answer is magnets! It sounds like a trick, but engineers really use it. https://socialmedia.xdme.com/tony/videos-book21/page-141.mp4 https://www.youtube.com/embed/ZRm_Egq4JFg 118 2026-10-05T09:25:57+00:00 yes https://xdme.com/watch-book21-q142.html https://xdme.com/book21-thumbs/page-142.jpg Do Auroras Glow on Jupiter and Saturn Too? You may have heard of the auroras on Earth, the colorful northern and southern lights. But they are not only on Earth! Let's visit other planets to see their glowing skies, and fin https://socialmedia.xdme.com/tony/videos-book21/page-142.mp4 https://www.youtube.com/embed/IeQZ_vsyBAM 110 2026-10-05T09:29:00+00:00 yes https://xdme.com/watch-book21-q143.html https://xdme.com/book21-thumbs/page-143.jpg Why Are Small Magnets Dangerous If Swallowed? Small magnets are fun to play with, but they have a dangerous side. If you swallow them, they can hurt you. This is one of the most important safety lessons of all, so let's listen https://socialmedia.xdme.com/tony/videos-book21/page-143.mp4 https://www.youtube.com/embed/0VBf2HBoBCo 104 2026-10-05T09:31:31+00:00 yes https://xdme.com/watch-book21-q144.html https://xdme.com/book21-thumbs/page-144.jpg Why Should You Keep Strong Magnets Away From Phones and Bank Cards? Strong magnets are amazing, but they do not belong next to your favorite gadgets. A magnet can scramble a bank card or confuse a phone. https://socialmedia.xdme.com/tony/videos-book21/page-144.mp4 https://www.youtube.com/embed/rWfTzcVAjrE 114 2026-10-05T09:35:06+00:00 yes https://xdme.com/watch-book21-q145.html https://xdme.com/book21-thumbs/page-145.jpg Why Can Strong Magnets Pinch Fingers and Shatter? Super-strong neodymium magnets are not toys. They can pinch a finger badly, and they can even shatter like glass. Let's learn why, and how to stay safe. https://socialmedia.xdme.com/tony/videos-book21/page-145.mp4 https://www.youtube.com/embed/9zyPf6qrZgQ 113 2026-10-05T09:38:09+00:00 yes https://xdme.com/watch-book21-q146.html https://xdme.com/book21-thumbs/page-146.jpg Why Must Some People Stay Away From Strong Magnets? Some people have special medical devices inside their bodies that help them stay healthy. Strong magnets can affect those devices. https://socialmedia.xdme.com/tony/videos-book21/page-146.mp4 https://www.youtube.com/embed/Z08ojKroQAI 114 2026-10-05T09:41:13+00:00 yes https://xdme.com/watch-book21-q147.html https://xdme.com/book21-thumbs/page-147.jpg How Should You Store Magnets? You have learned lots of cool things about magnets. Now here is how to take care of them. Storing magnets the right way keeps them strong, and keeps everyone safe. https://socialmedia.xdme.com/tony/videos-book21/page-147.mp4 https://www.youtube.com/embed/RD8mwgyaQYE 107 2026-10-05T09:44:20+00:00 yes https://xdme.com/watch-book21-q148.html https://xdme.com/book21-thumbs/page-148.jpg How Can You Tell If a Magnet Toy Is a Safe Choice? Magnet toys can be great fun, but not every magnet toy is right for every age. How can you tell if one is a safe choice? Let's learn the checklist that grown-ups use! https://socialmedia.xdme.com/tony/videos-book21/page-148.mp4 https://www.youtube.com/embed/OIpvcLCO4f0 104 2026-10-05T09:47:23+00:00 yes https://xdme.com/watch-book21-q149.html https://xdme.com/book21-thumbs/page-149.jpg What Are the Safe Rules for Magnet Experiments? Magnet experiments are great fun, and they are safe when you follow the rules. Think of the rules as the science lab's safety net. Real scientists follow rules like these every sin https://socialmedia.xdme.com/tony/videos-book21/page-149.mp4 https://www.youtube.com/embed/CuwPGnGe_8Y 113 2026-10-05T09:50:36+00:00 yes https://xdme.com/watch-book21-q150.html https://xdme.com/book21-thumbs/page-150.jpg What Magnet Mysteries Are Scientists Still Trying to Solve? You have learned a lot about magnets in this journey. But scientists still have big magnet mysteries to solve. Some of the strongest magnets in the world are built to study new mat https://socialmedia.xdme.com/tony/videos-book21/page-150.mp4 https://www.youtube.com/embed/swrfJoPUHIk 109 2026-10-05T09:53:38+00:00 yes https://xdme.com/watch-book22-q001.html https://xdme.com/book22-thumbs/page-001.jpg What Exactly Is Energy? Energy is the ability to make something change or move. It is what lets a ball roll, a plant grow, a bulb glow, and a kid run. You cannot hold it in your hand, but you can see what https://socialmedia.xdme.com/tony/videos-book22/page-001.mp4 https://www.youtube.com/embed/XqO1pO-f9-A 114 2026-10-05T10:09:50+00:00 yes https://xdme.com/watch-book22-q002.html https://xdme.com/book22-thumbs/page-002.jpg How Can You Tell Energy Is There When You Can’t See It? Energy is never seen on its own. It is a bit like wind, which you only see in the leaves it moves. So how do we know energy is there? https://socialmedia.xdme.com/tony/videos-book22/page-002.mp4 https://www.youtube.com/embed/Y8UAaxnalPU 107 2026-10-05T10:09:51+00:00 yes https://xdme.com/watch-book22-q003.html https://xdme.com/book22-thumbs/page-003.jpg What Kinds of Energy Are There? Energy comes in many forms. Moving things, hot things, light, sound, and electricity are all energy. Let's meet the family! All the forms of energy can change from one into another https://socialmedia.xdme.com/tony/videos-book22/page-003.mp4 https://www.youtube.com/embed/Ygv8jIAm8js 119 2026-10-05T10:09:53+00:00 yes https://xdme.com/watch-book22-q004.html https://xdme.com/book22-thumbs/page-004.jpg How Is Stored Energy Different From Moving Energy? Stored energy is energy that is waiting to be used. Moving energy is energy that is happening right now. And one can turn into the other! https://socialmedia.xdme.com/tony/videos-book22/page-004.mp4 https://www.youtube.com/embed/JxrvRP6F6co 112 2026-10-05T10:09:55+00:00 yes https://xdme.com/watch-book22-q005.html https://xdme.com/book22-thumbs/page-005.jpg Why Can Energy Never Be Made or Destroyed? Scientists have tested this for more than a hundred and fifty years. Energy is never made from nothing, and it never disappears. It only changes form! https://socialmedia.xdme.com/tony/videos-book22/page-005.mp4 https://www.youtube.com/embed/dGhW1tNcNOk 110 2026-10-05T10:09:57+00:00 yes https://xdme.com/watch-book22-q006.html https://xdme.com/book22-thumbs/page-006.jpg Where Does a Ball’s Energy Go When It Stops Rolling? A rolling ball slowly slows down and stops. But the ball's energy does not simply disappear. So where does it go? Friction always turns some motion energy into heat. https://socialmedia.xdme.com/tony/videos-book22/page-006.mp4 https://www.youtube.com/embed/UkQe2gh-_Uk 110 2026-10-05T10:11:53+00:00 yes https://xdme.com/watch-book22-q007.html https://xdme.com/book22-thumbs/page-007.jpg What Does It Mean to “Use Up” Energy? People often say they use up energy. But energy never really vanishes. So what are we really using up? Energy does not vanish when a battery runs flat. https://socialmedia.xdme.com/tony/videos-book22/page-007.mp4 https://www.youtube.com/embed/xLtTJvXH6CI 110 2026-10-05T10:13:55+00:00 yes https://xdme.com/watch-book22-q008.html https://xdme.com/book22-thumbs/page-008.jpg Why Does a Stretched Rubber Band Hold Energy? A stretched rubber band can fling a paper ball across a room. That is because stretching stores energy. A stretched rubber band stores energy just like a coiled spring. https://socialmedia.xdme.com/tony/videos-book22/page-008.mp4 https://www.youtube.com/embed/oUTZ8nDETY4 111 2026-10-05T10:16:57+00:00 yes https://xdme.com/watch-book22-q009.html https://xdme.com/book22-thumbs/page-009.jpg Why Does a Book on a High Shelf Hold Energy? A book sitting on a high shelf looks very still. But it is secretly holding energy! Here is why. The higher the shelf, the more energy the book stores. https://socialmedia.xdme.com/tony/videos-book22/page-009.mp4 https://www.youtube.com/embed/Vo6bJjLtNro 109 2026-10-05T10:20:12+00:00 yes https://xdme.com/watch-book22-q010.html https://xdme.com/book22-thumbs/page-010.jpg What Is the Energy Hiding in Food, Fuel, and Batteries? Food, fuel, and batteries all have energy hiding inside. It is called chemical energy. A single spoonful of sugar holds enough chemical energy for a short walk. https://socialmedia.xdme.com/tony/videos-book22/page-010.mp4 https://www.youtube.com/embed/m1Pt7RE2hUg 118 2026-10-05T10:23:15+00:00 yes https://xdme.com/watch-book22-q011.html https://xdme.com/book22-thumbs/page-011.jpg Why Do Scientists Call Heat Energy on the Move? Heat is energy that moves from a warmer thing to a cooler thing. That is why scientists call it energy on the move. Let's watch it travel! https://socialmedia.xdme.com/tony/videos-book22/page-011.mp4 https://www.youtube.com/embed/HelElN6BTQc 110 2026-10-05T10:26:17+00:00 yes https://xdme.com/watch-book22-q012.html https://xdme.com/book22-thumbs/page-012.jpg How Does Energy Change From One Form Into Another? Energy changes form whenever something happens. A toaster, a battery, a plant, and your muscles all do it. Let's follow the changes! https://socialmedia.xdme.com/tony/videos-book22/page-012.mp4 https://www.youtube.com/embed/T1tCvYzSmU0 116 2026-10-05T10:29:20+00:00 yes https://xdme.com/watch-book22-q013.html https://xdme.com/book22-thumbs/page-013.jpg How Can You Follow Energy From the Sun to Your Toast? The toast on your plate holds energy that started in the Sun. Sunlight traveled a very long way to get there. Let's follow the whole path! https://socialmedia.xdme.com/tony/videos-book22/page-013.mp4 https://www.youtube.com/embed/7ZMJmJIzffk 108 2026-10-05T10:32:22+00:00 yes https://xdme.com/watch-book22-q014.html https://xdme.com/book22-thumbs/page-014.jpg Why Do Machines Waste Some Energy? In every machine, some energy turns into heat that nobody wanted. Engineers call that wasted energy. A gasoline car engine turns only about a quarter of the fuel's energy into moti https://socialmedia.xdme.com/tony/videos-book22/page-014.mp4 https://www.youtube.com/embed/NJutyUK7cLE 112 2026-10-05T10:35:25+00:00 yes https://xdme.com/watch-book22-q015.html https://xdme.com/book22-thumbs/page-015.jpg What Does “Work” Mean in Science? In everyday talk, work means a job or a task. But in science, work has a special meaning. In science, work happens only when a force moves something. https://socialmedia.xdme.com/tony/videos-book22/page-015.mp4 https://www.youtube.com/embed/ElLE3hpNg2c 111 2026-10-05T10:38:28+00:00 yes https://xdme.com/watch-book22-q016.html https://xdme.com/book22-thumbs/page-016.jpg What Is Power, and How Is It Different From Energy? Energy is the total amount, and power is how fast energy is used. Two people can use the same energy at different speeds. Let's compare them! https://socialmedia.xdme.com/tony/videos-book22/page-016.mp4 https://www.youtube.com/embed/7oOEWW2TsZg 112 2026-10-05T10:42:02+00:00 yes https://xdme.com/watch-book22-q017.html https://xdme.com/book22-thumbs/page-017.jpg How Do We Count Energy? Energy can be counted with several different units. Scientists, food labels, and electric companies each choose their own. Let's compare them! https://socialmedia.xdme.com/tony/videos-book22/page-017.mp4 https://www.youtube.com/embed/OiCLhQIq1Cw 117 2026-10-05T10:45:35+00:00 yes https://xdme.com/watch-book22-q018.html https://xdme.com/book22-thumbs/page-018.jpg How Did James Joule Show That Motion Can Turn Into Heat? Long ago, a scientist named James Joule had a big question. Could motion turn into heat? He built a clever machine to find out! James Joule did his famous work in the 1840s. https://socialmedia.xdme.com/tony/videos-book22/page-018.mp4 https://www.youtube.com/embed/2cvwSiqcExQ 105 2026-10-05T10:49:09+00:00 yes https://xdme.com/watch-book22-q019.html https://xdme.com/book22-thumbs/page-019.jpg Do Rocks and Mountains Have Energy? A rock sitting on the ground looks completely still. But does it have energy? The answer is yes! Even a cold rock holds lots of thermal energy because its atoms never stop moving. https://socialmedia.xdme.com/tony/videos-book22/page-019.mp4 https://www.youtube.com/embed/v0al1YkHP5Y 108 2026-10-05T10:52:11+00:00 yes https://xdme.com/watch-book22-q020.html https://xdme.com/book22-thumbs/page-020.jpg Why Do People Say “Save Energy” If Energy Never Disappears? Energy never disappears, so why do people say save energy? It is because useful energy can run out. Energy is never destroyed, but the useful kind can run out. https://socialmedia.xdme.com/tony/videos-book22/page-020.mp4 https://www.youtube.com/embed/GwW9coRjML4 114 2026-10-05T10:55:23+00:00 yes https://xdme.com/watch-book22-q021.html https://xdme.com/book22-thumbs/page-021.jpg What Happens to Energy When Two Things Bump? Energy can hop from one thing to another when they bump. A moving ball, a warm hand, and even a sound all pass it along. Energy is always handed on! https://socialmedia.xdme.com/tony/videos-book22/page-021.mp4 https://www.youtube.com/embed/v_GC9HtL_xE 108 2026-10-05T10:58:26+00:00 yes https://xdme.com/watch-book22-q022.html https://xdme.com/book22-thumbs/page-022.jpg Why Does It Take Energy to Make Something Move, Even a Little? A still object likes to stay still. To get it moving, you must give it some energy. Even a small push counts! A big truck needs a lot more energy than a bike to get going. https://socialmedia.xdme.com/tony/videos-book22/page-022.mp4 https://www.youtube.com/embed/vssxBrm2MEg 111 2026-10-05T11:01:28+00:00 yes https://xdme.com/watch-book22-q023.html https://xdme.com/book22-thumbs/page-023.jpg Is There Energy Inside Atoms? Atoms are unbelievably tiny. But there is energy inside them in more than one way. Let's peek inside! Atoms hold energy in many different ways. https://socialmedia.xdme.com/tony/videos-book22/page-023.mp4 https://www.youtube.com/embed/5bkrVoerOl0 110 2026-10-05T11:04:31+00:00 yes https://xdme.com/watch-book22-q024.html https://xdme.com/book22-thumbs/page-024.jpg Can a Wave Carry Energy Without Carrying Stuff Along? A wave carries energy from one place to another. But the stuff it moves through barely travels at all. A duck on a lake bobs up and down while the waves roll past. https://socialmedia.xdme.com/tony/videos-book22/page-024.mp4 https://www.youtube.com/embed/mHBLBUyzhwQ 107 2026-10-05T11:07:36+00:00 yes https://xdme.com/watch-book22-q025.html https://xdme.com/book22-thumbs/page-025.jpg Why Can’t We Build a Machine That Runs Forever? Imagine a machine that runs forever with no fuel at all. People have dreamed about it for hundreds of years. But it can never work! https://socialmedia.xdme.com/tony/videos-book22/page-025.mp4 https://www.youtube.com/embed/KsQ-vancns8 114 2026-10-05T11:11:09+00:00 yes https://xdme.com/watch-book22-q026.html https://xdme.com/book22-thumbs/page-026.jpg What Is Kinetic Energy, the Energy of Motion? Kinetic energy is the energy of motion. Anything that moves has it. The word kinetic comes from a Greek word that means moving. Anything that moves has kinetic energy. https://socialmedia.xdme.com/tony/videos-book22/page-026.mp4 https://www.youtube.com/embed/IEyv8QeBo-E 114 2026-10-05T11:14:19+00:00 yes https://xdme.com/watch-book22-q027.html https://xdme.com/book22-thumbs/page-027.jpg Why Does a Diver on a High Board Hold Potential Energy? A diver on a high board is standing still. But she is holding a lot of energy! It is called potential energy. Potential energy can be stored for years and released in a second. https://socialmedia.xdme.com/tony/videos-book22/page-027.mp4 https://www.youtube.com/embed/RZTxPj43IIs 112 2026-10-05T11:17:53+00:00 yes https://xdme.com/watch-book22-q028.html https://xdme.com/book22-thumbs/page-028.jpg Why Does Speed Matter So Much for Moving Energy? A moving thing's energy grows fast with its speed. Double the speed, and the energy does not just double. It becomes four times bigger! https://socialmedia.xdme.com/tony/videos-book22/page-028.mp4 https://www.youtube.com/embed/I4xdG3CoI5I 110 2026-10-05T11:20:55+00:00 yes https://xdme.com/watch-book22-q029.html https://xdme.com/book22-thumbs/page-029.jpg Why Does a Heavy Truck Have So Much More Moving Energy than a Bicycle? A heavy truck and a bicycle can roll at the same speed. But the truck carries far more moving energy. A fully loaded truck can weigh twenty times more than a family car. https://socialmedia.xdme.com/tony/videos-book22/page-029.mp4 https://www.youtube.com/embed/usUAomcTRd8 108 2026-10-05T11:24:30+00:00 yes https://xdme.com/watch-book22-q030.html https://xdme.com/book22-thumbs/page-030.jpg How Does a Roller Coaster Trade Height for Speed? A roller coaster climbs a big hill very slowly. Then it zooms down at top speed! The tallest hill on many coasters is right at the start. https://socialmedia.xdme.com/tony/videos-book22/page-030.mp4 https://www.youtube.com/embed/dNL45fYnxvQ 107 2026-10-05T11:27:32+00:00 yes https://xdme.com/watch-book22-q031.html https://xdme.com/book22-thumbs/page-031.jpg Why Does a Pendulum Swing Back and Forth? A pendulum is just a weight hanging from a string. Yet it swings back and forth in a steady rhythm. A pendulum takes almost the same time for each swing, no matter how wide the swi https://socialmedia.xdme.com/tony/videos-book22/page-031.mp4 https://www.youtube.com/embed/oZCzxVBHdlI 111 2026-10-05T11:31:05+00:00 yes https://xdme.com/watch-book22-q032.html https://xdme.com/book22-thumbs/page-032.jpg Why Does a Ball Speed Up Faster on a Steeper Hill? A ball rolling down a steep hill speeds up fast. On a gentle hill, it speeds up slowly. Galileo rolled balls down ramps about four hundred years ago to study how things speed up. https://socialmedia.xdme.com/tony/videos-book22/page-032.mp4 https://www.youtube.com/embed/Y4C0f4YMzdI 105 2026-10-05T11:34:08+00:00 yes https://xdme.com/watch-book22-q033.html https://xdme.com/book22-thumbs/page-033.jpg Where Does a Squashed Spring’s Stored Energy Go When You Let Go? Squeezing or stretching a spring puts energy into it. Let go, and it springs right back! Where does that stored energy go? Springs inside a car help smooth out bumps by squeezing a https://socialmedia.xdme.com/tony/videos-book22/page-033.mp4 https://www.youtube.com/embed/f9T_LeXJuis 110 2026-10-05T11:37:41+00:00 yes https://xdme.com/watch-book22-q034.html https://xdme.com/book22-thumbs/page-034.jpg How Does a Wind-Up Toy Store Energy? A wind-up toy walks, hops, or rolls without a battery. The secret is a twisted metal spring inside. Let's open it up! Wind-up clocks and music boxes have used springs for hundreds https://socialmedia.xdme.com/tony/videos-book22/page-034.mp4 https://www.youtube.com/embed/BRNYkopywU0 108 2026-10-05T11:40:46+00:00 yes https://xdme.com/watch-book22-q035.html https://xdme.com/book22-thumbs/page-035.jpg Why Does Falling From Higher Up Hurt More? Falling from higher up hurts more than falling from low. Energy is the reason. Soft surfaces spread the stopping out over a longer time, which lowers the force. https://socialmedia.xdme.com/tony/videos-book22/page-035.mp4 https://www.youtube.com/embed/lzMwUWJ2fVQ 108 2026-10-05T11:43:48+00:00 yes https://xdme.com/watch-book22-q036.html https://xdme.com/book22-thumbs/page-036.jpg How Does a Moving Bowling Ball Pass Energy to the Pins? A rolling bowling ball is full of moving energy. When it crashes into the pins, they fly everywhere. Let's follow the energy! Pins are lighter than the ball, so they speed up when https://socialmedia.xdme.com/tony/videos-book22/page-036.mp4 https://www.youtube.com/embed/_FzPQLSF3eM 106 2026-10-05T11:47:21+00:00 yes https://xdme.com/watch-book22-q037.html https://xdme.com/book22-thumbs/page-037.jpg Why Can One Domino Knock Over a Whole Row? Line up lots of dominoes and tip the first one. Click, click, click, they all fall down! How does one domino topple them all? Each domino can topple one about one and a half times https://socialmedia.xdme.com/tony/videos-book22/page-037.mp4 https://www.youtube.com/embed/Fr0RgFGCuPY 108 2026-10-05T11:50:24+00:00 yes https://xdme.com/watch-book22-q038.html https://xdme.com/book22-thumbs/page-038.jpg Where Does the Energy Come From When You Jump? When you jump, you go up in the air all by yourself. Where does the energy for that come from? Your muscles and your lunch! On the Moon, the same jump would take you about six time https://socialmedia.xdme.com/tony/videos-book22/page-038.mp4 https://www.youtube.com/embed/4D88yqvzPII 105 2026-10-05T11:53:39+00:00 yes https://xdme.com/watch-book22-q039.html https://xdme.com/book22-thumbs/page-039.jpg How Does a Toy Catapult Launch Things? A toy catapult can toss a soft pom-pom across the room. It does that with stored energy. Let's build the idea! The arm of a catapult is a lever, which makes the throw faster. https://socialmedia.xdme.com/tony/videos-book22/page-039.mp4 https://www.youtube.com/embed/i9G96-X04mY 109 2026-10-05T11:57:11+00:00 yes https://xdme.com/watch-book22-q040.html https://xdme.com/book22-thumbs/page-040.jpg How Does a Cyclist Use Energy to Climb a Hill and Then Coast? Pedaling uphill is hard work. But coasting down feels like magic. Let's follow the energy! Coasting downhill can be faster than pedaling on flat ground. https://socialmedia.xdme.com/tony/videos-book22/page-040.mp4 https://www.youtube.com/embed/lwj5w6Yhmnk 113 2026-10-05T12:00:44+00:00 yes https://xdme.com/watch-book22-q041.html https://xdme.com/book22-thumbs/page-041.jpg Where Does the Energy Go When Bike Brakes Stop You? When you squeeze bike brakes, you slow down quickly. But the moving energy does not just vanish. It turns into something else! The faster you go, the more heat the brakes have to c https://socialmedia.xdme.com/tony/videos-book22/page-041.mp4 https://www.youtube.com/embed/akBVHXJHelE 109 2026-10-05T12:03:48+00:00 yes https://xdme.com/watch-book22-q042.html https://xdme.com/book22-thumbs/page-042.jpg How Do Electric and Hybrid Cars Save Energy While Braking? Most brakes turn a car's moving energy into wasted heat. But electric and hybrid cars have a clever trick. They save the energy to use again! https://socialmedia.xdme.com/tony/videos-book22/page-042.mp4 https://www.youtube.com/embed/FyX9NDNm_pQ 116 2026-10-05T12:07:21+00:00 yes https://xdme.com/watch-book22-q043.html https://xdme.com/book22-thumbs/page-043.jpg How Does a Flywheel Store Energy? A flywheel is just a heavy wheel that spins. Once it gets going, it just keeps on spinning. That makes it a great energy store! Some old buses ran on large spinning flywheels. https://socialmedia.xdme.com/tony/videos-book22/page-043.mp4 https://www.youtube.com/embed/O_2Omb22Usg 106 2026-10-05T12:10:56+00:00 yes https://xdme.com/watch-book22-q044.html https://xdme.com/book22-thumbs/page-044.jpg How Does a Hand-Crank Flashlight Work Without Batteries? A hand-crank flashlight has no batteries to replace. You just turn the crank, and the light comes on. How does that work? Hand-crank radios and chargers use the same idea. https://socialmedia.xdme.com/tony/videos-book22/page-044.mp4 https://www.youtube.com/embed/l6Hj1j3Q_cI 115 2026-10-05T12:14:04+00:00 yes https://xdme.com/watch-book22-q045.html https://xdme.com/book22-thumbs/page-045.jpg How Does a Yo-Yo Store Spinning Energy? A yo-yo drops, spins, and climbs right back up your hand. The secret is spinning energy. Let's watch it work! A well-made yo-yo can sleep at the end of the string, spinning for man https://socialmedia.xdme.com/tony/videos-book22/page-045.mp4 https://www.youtube.com/embed/igD3dKQH5hI 108 2026-10-05T12:17:07+00:00 yes https://xdme.com/watch-book22-q046.html https://xdme.com/book22-thumbs/page-046.jpg How Does a Balloon Rocket Use Stored Energy? A blown-up balloon holds energy in the air inside it. Let it go, and it zooms around the room! Let's learn the secret. A balloon filled with more air flies farther. https://socialmedia.xdme.com/tony/videos-book22/page-046.mp4 https://www.youtube.com/embed/Zx1MuymhPSk 107 2026-10-05T12:20:42+00:00 yes https://xdme.com/watch-book22-q047.html https://xdme.com/book22-thumbs/page-047.jpg Why Does a Pogo Stick Make You Bounce? A pogo stick lets you bounce up and down like a kangaroo. The secret is a strong spring. Kangaroos have springy tendons in their legs that store energy for each hop. https://socialmedia.xdme.com/tony/videos-book22/page-047.mp4 https://www.youtube.com/embed/zDabYWRPQlY 110 2026-10-05T12:24:25+00:00 yes https://xdme.com/watch-book22-q048.html https://xdme.com/book22-thumbs/page-048.jpg How Does a Zipline Turn Height Into Speed? A zipline sends riders gliding along a cable. They start high and end low. Longer ziplines can have a drop of hundreds of feet. Height at the start turns into speed on the way down https://socialmedia.xdme.com/tony/videos-book22/page-048.mp4 https://www.youtube.com/embed/asO4y6-n0Zo 109 2026-10-05T12:28:08+00:00 yes https://xdme.com/watch-book22-q049.html https://xdme.com/book22-thumbs/page-049.jpg Why Is a Heavy Box Harder to Push than an Empty One? A heavy box is harder to push than an empty one. You may think it is only because it weighs more. But friction has a big part in it! https://socialmedia.xdme.com/tony/videos-book22/page-049.mp4 https://www.youtube.com/embed/_WJJEuRNbQQ 106 2026-10-05T12:30:40+00:00 yes https://xdme.com/watch-book22-q050.html https://xdme.com/book22-thumbs/page-050.jpg How Do Helmets and Padding Soak Up Moving Energy? A helmet has soft foam inside. When something hits it, the foam squashes. That squashing protects your head! Padding spreads the force of an impact over a wider area. https://socialmedia.xdme.com/tony/videos-book22/page-050.mp4 https://www.youtube.com/embed/VQLXj1JGesA 113 2026-10-05T12:34:17+00:00 yes https://xdme.com/watch-book22-q051.html https://xdme.com/book22-thumbs/page-051.jpg How Does the Sun’s Energy Cross Empty Space to Reach Us? The space between the Sun and Earth is almost completely empty. There is no air to carry heat across it. So how does sunshine get here? https://socialmedia.xdme.com/tony/videos-book22/page-051.mp4 https://www.youtube.com/embed/KnL6SBbd2A8 109 2026-10-05T12:37:19+00:00 yes https://xdme.com/watch-book22-q052.html https://xdme.com/book22-thumbs/page-052.jpg What Makes the Sun Give Off So Much Energy? The Sun gives off an amazing amount of energy every single second. Where does it all come from? Deep inside, something powerful is happening! https://socialmedia.xdme.com/tony/videos-book22/page-052.mp4 https://www.youtube.com/embed/2Zi-7AKly94 117 2026-10-05T12:40:53+00:00 yes https://xdme.com/watch-book22-q053.html https://xdme.com/book22-thumbs/page-053.jpg How Much of the Sun’s Energy Does Earth Actually Catch? The Sun sends its light out in every direction. Earth is a small target, far away. So how much do we actually catch? Earth catches only about one two-billionth of the Sun's energy. https://socialmedia.xdme.com/tony/videos-book22/page-053.mp4 https://www.youtube.com/embed/_0R3ZmSo02I 108 2026-10-05T12:44:26+00:00 yes https://xdme.com/watch-book22-q054.html https://xdme.com/book22-thumbs/page-054.jpg How Can Heat Travel From Place to Place? Heat does not stay in one place. It moves in three different ways. Let's learn all three! Radiation is the only way heat can travel through empty space. https://socialmedia.xdme.com/tony/videos-book22/page-054.mp4 https://www.youtube.com/embed/D_hfb-tpkso 117 2026-10-05T12:47:27+00:00 yes https://xdme.com/watch-book22-q055.html https://xdme.com/book22-thumbs/page-055.jpg Which Holds More Heat: a Cup of Hot Tea or a Tub of Warm Water? Which holds more heat, a small cup of hot tea or a big tub of warm water? Most people guess the tea. The real answer may surprise you! https://socialmedia.xdme.com/tony/videos-book22/page-055.mp4 https://www.youtube.com/embed/1pZFDhIRj-0 108 2026-10-05T12:50:30+00:00 yes https://xdme.com/watch-book22-q056.html https://xdme.com/book22-thumbs/page-056.jpg How Does a Blanket Keep You Warm If It Makes No Heat? A blanket feels so warm and cozy. But a blanket makes no heat at all! So how does it keep you warm? Fluffy blankets trap more air and keep you warmer than thin ones. https://socialmedia.xdme.com/tony/videos-book22/page-056.mp4 https://www.youtube.com/embed/NDX5u29DQeE 108 2026-10-05T12:54:03+00:00 yes https://xdme.com/watch-book22-q057.html https://xdme.com/book22-thumbs/page-057.jpg How Does a Leaf Turn Sunshine Into Food? A green leaf is a tiny food factory. It runs on sunshine! A leaf stores only a few percent of the sunlight that hits it. The sugar stores that energy as chemical energy. https://socialmedia.xdme.com/tony/videos-book22/page-057.mp4 https://www.youtube.com/embed/C-XRZgfFdd4 111 2026-10-05T12:58:06+00:00 yes https://xdme.com/watch-book22-q058.html https://xdme.com/book22-thumbs/page-058.jpg How Is a Solar Water Heater Different From a Solar Panel? Rooftops can use the Sun in two different ways. One makes hot water, and the other makes electricity. Many warm countries have solar water heaters on rooftops. https://socialmedia.xdme.com/tony/videos-book22/page-058.mp4 https://www.youtube.com/embed/9eBmzHTtUjE 114 2026-10-05T13:01:42+00:00 yes https://xdme.com/watch-book22-q059.html https://xdme.com/book22-thumbs/page-059.jpg What Is Infrared Light? Beyond the red light you can see, there is another kind of light. Your eyes cannot see it. But your skin can feel it! Some snakes can sense infrared light from warm animals. https://socialmedia.xdme.com/tony/videos-book22/page-059.mp4 https://www.youtube.com/embed/4QpD1YL-xwY 112 2026-10-05T13:05:47+00:00 yes https://xdme.com/watch-book22-q060.html https://xdme.com/book22-thumbs/page-060.jpg Why Does a Parked Car Get So Hot with the Windows Closed? A parked car can get dangerously hot, even on a mild day. Sunlight gets in easily. But the heat has trouble getting out! On a warm day, a closed car can heat up by twenty degrees F https://socialmedia.xdme.com/tony/videos-book22/page-060.mp4 https://www.youtube.com/embed/1lDSJxz2PQY 113 2026-10-05T13:09:20+00:00 yes https://xdme.com/watch-book22-q061.html https://xdme.com/book22-thumbs/page-061.jpg Why Do Very Hot Things Glow? When something gets hot enough, it begins to glow. The hotter it gets, the more the color changes. Let's watch the colors climb! The wire in an old light bulb reaches about forty-f https://socialmedia.xdme.com/tony/videos-book22/page-061.mp4 https://www.youtube.com/embed/9wRGyk3vdo4 110 2026-10-05T13:16:01+00:00 yes https://xdme.com/watch-book22-q062.html https://xdme.com/book22-thumbs/page-062.jpg Why Does Sand Heat Up Faster than Water? On a sunny beach, the sand feels scorching hot. But the water feels cool, even after the same hours of sun. Why do they heat up so differently? https://socialmedia.xdme.com/tony/videos-book22/page-062.mp4 https://www.youtube.com/embed/wIAU0T1yXe8 110 2026-10-05T13:19:03+00:00 yes https://xdme.com/watch-book22-q063.html https://xdme.com/book22-thumbs/page-063.jpg How Does the Sun’s Energy Keep Water Moving Around the Planet? The Sun does not only light our days. It also keeps water moving around the whole planet. Let's follow a drop on its trip! Every day, the Sun lifts enough water into the air to fil https://socialmedia.xdme.com/tony/videos-book22/page-063.mp4 https://www.youtube.com/embed/bt7anMzBiNE 111 2026-10-05T13:22:07+00:00 yes https://xdme.com/watch-book22-q064.html https://xdme.com/book22-thumbs/page-064.jpg What Invisible Rays Does the Sun Send Us? Sunlight is more than the light we can see. It also carries invisible rays. Some feel warm, and some can hurt! UV light can pass through clouds, so you can burn on a cloudy day. https://socialmedia.xdme.com/tony/videos-book22/page-064.mp4 https://www.youtube.com/embed/4NzKz_smGTA 120 2026-10-05T13:25:40+00:00 yes https://xdme.com/watch-book22-q065.html https://xdme.com/book22-thumbs/page-065.jpg How Much Power Does Sunshine Bring to One Square Meter? Sunshine brings real power to the ground. Let's measure how much lands on one square meter. A square meter is about the size of a small table top. https://socialmedia.xdme.com/tony/videos-book22/page-065.mp4 https://www.youtube.com/embed/hWK4GXYwpvk 108 2026-10-05T13:29:14+00:00 yes https://xdme.com/watch-book22-q066.html https://xdme.com/book22-thumbs/page-066.jpg How Did People Long Ago Put Sunshine to Work? People have used the Sun's energy for thousands of years. Long before electric power, they put sunshine to work. Remember, sun-dried bricks called adobe are still used in warm, dry https://socialmedia.xdme.com/tony/videos-book22/page-066.mp4 https://www.youtube.com/embed/TJtNie_lr9U 122 2026-10-05T13:32:47+00:00 yes https://xdme.com/watch-book22-q067.html https://xdme.com/book22-thumbs/page-067.jpg How Much Power Does a Solar Panel Lose When Clouds Roll In? Solar panels love sunshine. But clouds sometimes roll in and cover the sky. So what happens to the power? Some countries with cloudy weather still use lots of solar power. https://socialmedia.xdme.com/tony/videos-book22/page-067.mp4 https://www.youtube.com/embed/q5_RfWC_Wl4 108 2026-10-05T13:36:23+00:00 yes https://xdme.com/watch-book22-q068.html https://xdme.com/book22-thumbs/page-068.jpg How Does a Thermos Keep Soup Warm? A thermos keeps soup hot for hours. It can also keep a cold drink cold. The thermos was invented in the 1890s by a scientist named James Dewar. https://socialmedia.xdme.com/tony/videos-book22/page-068.mp4 https://www.youtube.com/embed/X_cwz7gobnU 111 2026-10-05T13:39:55+00:00 yes https://xdme.com/watch-book22-q069.html https://xdme.com/book22-thumbs/page-069.jpg How Does a Hot-Water Radiator Warm a Room? A radiator can warm a whole room. It does it without any fan or blowing. A radiator heats a room mostly by moving warm air around. https://socialmedia.xdme.com/tony/videos-book22/page-069.mp4 https://www.youtube.com/embed/K2LMWhNmurs 111 2026-10-05T13:42:58+00:00 yes https://xdme.com/watch-book22-q070.html https://xdme.com/book22-thumbs/page-070.jpg What Happens to Light When Something Swallows It? When light hits something, it can bounce off or get swallowed. Swallowed light turns into heat. That is why a black shirt feels so warm in the sun! https://socialmedia.xdme.com/tony/videos-book22/page-070.mp4 https://www.youtube.com/embed/9XhHq_KlOeY 113 2026-10-05T13:46:32+00:00 yes https://xdme.com/watch-book22-q071.html https://xdme.com/book22-thumbs/page-071.jpg What Are the Tiny Packets of Energy in a Sunbeam? Light travels as a wave. But it also comes in tiny packets of energy called photons. Let's meet them! A single light bulb sends out trillions upon trillions of photons every second https://socialmedia.xdme.com/tony/videos-book22/page-071.mp4 https://www.youtube.com/embed/vXCTAQRHiFM 118 2026-10-05T13:50:36+00:00 yes https://xdme.com/watch-book22-q072.html https://xdme.com/book22-thumbs/page-072.jpg How Much Heat Does a Person Give Off? Sitting still, your body is giving off heat. In fact, you are about as warm as a bright light bulb! A group of twenty people in a room gives off about as much heat as twenty light https://socialmedia.xdme.com/tony/videos-book22/page-072.mp4 https://www.youtube.com/embed/YHVWTOZ7YNk 105 2026-10-05T13:54:09+00:00 yes https://xdme.com/watch-book22-q073.html https://xdme.com/book22-thumbs/page-073.jpg How Hot Is the Sun’s Surface, and How Hot Is Its Core? The Sun is a ball of glowing gas. But different parts of it have wildly different temperatures. The Sun's core is about twenty-seven hundred times hotter than its surface. https://socialmedia.xdme.com/tony/videos-book22/page-073.mp4 https://www.youtube.com/embed/5K0XkFVO29s 118 2026-10-05T13:57:42+00:00 yes https://xdme.com/watch-book22-q074.html https://xdme.com/book22-thumbs/page-074.jpg How Do Astronauts Keep Cool in Space Where There Is No Air? In space, there is no air at all. That means no breeze to cool an astronaut. So how do they keep from overheating? Parts of a spacecraft in the Sun can get hot, while parts in the https://socialmedia.xdme.com/tony/videos-book22/page-074.mp4 https://www.youtube.com/embed/rJofqwaS9QE 115 2026-10-05T18:21:01+00:00 yes https://xdme.com/watch-book22-q075.html https://xdme.com/book22-thumbs/page-075.jpg Why Doesn’t Earth Keep Getting Hotter If the Sun Keeps Sending Energy? The Sun keeps sending energy to Earth every day. So why doesn't our planet keep getting hotter and hotter? The answer is balance! Without any air, Earth would be much colder than i https://socialmedia.xdme.com/tony/videos-book22/page-075.mp4 https://www.youtube.com/embed/yF03aruvoWM 115 2026-10-05T18:23:34+00:00 yes https://xdme.com/watch-book22-q076.html https://xdme.com/book22-thumbs/page-076.jpg How Do Scientists Find Out How Much Energy Is in a Peanut? How could anyone measure the energy in a peanut? Scientists use a clever device. It is called a calorimeter! Peanuts are rich in fat, which stores lots of energy. https://socialmedia.xdme.com/tony/videos-book22/page-076.mp4 https://www.youtube.com/embed/GAsXACqHKNg 114 2026-10-05T10:09:58+00:00 yes https://xdme.com/watch-book22-q077.html https://xdme.com/book22-thumbs/page-077.jpg Why Is the Calorie on a Food Label Spelled with a Capital C? Food labels list Calories. You may have noticed that the word starts with a capital C. That is not a mistake! Many countries use kilojoules on food labels instead of Calories. https://socialmedia.xdme.com/tony/videos-book22/page-077.mp4 https://www.youtube.com/embed/l5NjqqDAk2g 110 2026-10-05T10:11:17+00:00 yes https://xdme.com/watch-book22-q078.html https://xdme.com/book22-thumbs/page-078.jpg How Does Your Body Get Energy Out of Food? Food has energy locked inside. Your body has to unlock it. The adventure starts in your mouth! Remember, your body can store extra glucose in your liver and muscles for later. https://socialmedia.xdme.com/tony/videos-book22/page-078.mp4 https://www.youtube.com/embed/bs8vM1nxnmU 114 2026-10-05T10:11:19+00:00 yes https://xdme.com/watch-book22-q079.html https://xdme.com/book22-thumbs/page-079.jpg How Do Your Cells Burn Food Without Fire? Your cells burn food, but there is no flame. There is no smoke or fire at all. So how do they do it? Mitochondria are often called the power plants of the cell. https://socialmedia.xdme.com/tony/videos-book22/page-079.mp4 https://www.youtube.com/embed/I6T6QbtWK_w 113 2026-10-05T10:11:20+00:00 yes https://xdme.com/watch-book22-q080.html https://xdme.com/book22-thumbs/page-080.jpg Why Does Your Body Make Its Own Heat? Your body makes its own heat. That is why you stay warm even when it is chilly outside. Let's learn how! Your brain, liver, and muscles make most of your heat. https://socialmedia.xdme.com/tony/videos-book22/page-080.mp4 https://www.youtube.com/embed/oDta49YaWr0 110 2026-10-05T10:11:21+00:00 yes https://xdme.com/watch-book22-q081.html https://xdme.com/book22-thumbs/page-081.jpg How Do Muscles Use Food Energy to Move? Every time you lift a spoon or kick a ball, your muscles are working. And muscles run on food energy. Muscles use energy even when you sit still, just less of it. https://socialmedia.xdme.com/tony/videos-book22/page-081.mp4 https://www.youtube.com/embed/Y41tGmRT-2w 111 2026-10-05T10:11:54+00:00 yes https://xdme.com/watch-book22-q082.html https://xdme.com/book22-thumbs/page-082.jpg Why Do Small Animals Eat So Much for Their Size? A tiny shrew eats almost all day long. An elephant eats a lot too, but far less for its size. Why do small animals eat so much? A hummingbird's heart can beat over a thousand times https://socialmedia.xdme.com/tony/videos-book22/page-082.mp4 https://www.youtube.com/embed/wXBUSCpQFWY 109 2026-10-05T10:13:56+00:00 yes https://xdme.com/watch-book22-q083.html https://xdme.com/book22-thumbs/page-083.jpg Why Do Reptiles Need Less Food than Mammals? A lizard sunbathes on a warm rock. Snakes can go weeks between meals. Why do reptiles eat so much less than mammals? A lizard may need about a tenth of the food a mammal of the sam https://socialmedia.xdme.com/tony/videos-book22/page-083.mp4 https://www.youtube.com/embed/7pOjhrbvMhA 108 2026-10-05T10:17:00+00:00 yes https://xdme.com/watch-book22-q084.html https://xdme.com/book22-thumbs/page-084.jpg Where Does Energy Go as It Moves Up a Food Chain? A rabbit eats grass, and a fox eats the rabbit. But energy gets smaller at every step. This is called the ten percent rule. Animals use most of their energy to move and stay warm. https://socialmedia.xdme.com/tony/videos-book22/page-084.mp4 https://www.youtube.com/embed/G65M-fGzPlU 106 2026-10-05T10:20:13+00:00 yes https://xdme.com/watch-book22-q085.html https://xdme.com/book22-thumbs/page-085.jpg Why Do Ecosystems Have So Many More Plants than Meat-Eaters? A meadow has thousands of grasshoppers. But it has only a few hawks. Energy is the reason! A large wild cat may need hundreds of square miles of land to find enough food. https://socialmedia.xdme.com/tony/videos-book22/page-085.mp4 https://www.youtube.com/embed/ZAuFHiRKKUI 114 2026-10-05T10:23:16+00:00 yes https://xdme.com/watch-book22-q086.html https://xdme.com/book22-thumbs/page-086.jpg How Do Plants Store the Energy They Make? Plants make sugar from sunshine. But they do not use it all at once. They save some for later! Rice, wheat, and corn are seeds packed with starch. https://socialmedia.xdme.com/tony/videos-book22/page-086.mp4 https://www.youtube.com/embed/uhwU71crJ80 111 2026-10-05T10:26:19+00:00 yes https://xdme.com/watch-book22-q087.html https://xdme.com/book22-thumbs/page-087.jpg What Makes Fat Such a Good Energy Bank? Bears, birds, and many other animals pack on fat. They do it before winter or a long trip. Fat is a super energy bank! A gram of fat holds about nine Calories, while a gram of suga https://socialmedia.xdme.com/tony/videos-book22/page-087.mp4 https://www.youtube.com/embed/I0Ayrl4K4ew 110 2026-10-05T10:29:21+00:00 yes https://xdme.com/watch-book22-q088.html https://xdme.com/book22-thumbs/page-088.jpg How Does Hibernating Save Energy? In winter, food is hard to find. Some animals just go to sleep for months. That trick is called hibernation! A hibernating ground squirrel's heart may beat only a few times a minut https://socialmedia.xdme.com/tony/videos-book22/page-088.mp4 https://www.youtube.com/embed/9wf7040jnA4 112 2026-10-05T10:32:23+00:00 yes https://xdme.com/watch-book22-q089.html https://xdme.com/book22-thumbs/page-089.jpg What Is Metabolism? Even when you are fast asleep, your body is busy. All the chemistry that keeps you going has a name. It is called metabolism! Remember, even when you rest, your body uses energy to https://socialmedia.xdme.com/tony/videos-book22/page-089.mp4 https://www.youtube.com/embed/XlZ9iJVvfzw 117 2026-10-05T10:35:26+00:00 yes https://xdme.com/watch-book22-q090.html https://xdme.com/book22-thumbs/page-090.jpg Where Does the Energy in Coal and Oil Come From? Coal and oil are burned to make power. But where did their energy come from in the first place? The answer goes back millions of years! https://socialmedia.xdme.com/tony/videos-book22/page-090.mp4 https://www.youtube.com/embed/YzV7bjkW7sQ 111 2026-10-05T10:38:29+00:00 yes https://xdme.com/watch-book22-q091.html https://xdme.com/book22-thumbs/page-091.jpg Why Does Burning Release Stored Energy? Fire is amazing and dangerous. Fuels like wood and gasoline hold lots of energy inside them. Burning is how they let it out! The leftovers from burning are mainly water vapor and c https://socialmedia.xdme.com/tony/videos-book22/page-091.mp4 https://www.youtube.com/embed/2kz4WdKKSck 115 2026-10-05T10:42:03+00:00 yes https://xdme.com/watch-book22-q092.html https://xdme.com/book22-thumbs/page-092.jpg Why Do Liquid Fuels Pack So Much Energy? A little liquid fuel can carry a huge amount of energy. Think of how far a tank of gasoline can take a car. One gallon of gasoline holds about as much energy as a hundred-watt bulb https://socialmedia.xdme.com/tony/videos-book22/page-092.mp4 https://www.youtube.com/embed/f8q03E4WuJ0 114 2026-10-05T10:45:36+00:00 yes https://xdme.com/watch-book22-q093.html https://xdme.com/book22-thumbs/page-093.jpg How Does a Car Engine Turn Fuel Into Motion? Under a car's hood, small explosions happen again and again. They turn fuel into motion. Let's follow the steps! A typical car engine has four to eight cylinders. https://socialmedia.xdme.com/tony/videos-book22/page-093.mp4 https://www.youtube.com/embed/ab8WZ5VHn-4 111 2026-10-05T10:49:10+00:00 yes https://xdme.com/watch-book22-q094.html https://xdme.com/book22-thumbs/page-094.jpg What Is Biofuel? Some fuel does not come from deep underground. It comes from plants that are growing right now. That is called biofuel! Remember, some buses and ships run on biodiesel. https://socialmedia.xdme.com/tony/videos-book22/page-094.mp4 https://www.youtube.com/embed/PFNFv07MjKo 116 2026-10-05T10:52:22+00:00 yes https://xdme.com/watch-book22-q095.html https://xdme.com/book22-thumbs/page-095.jpg How Did People First Use Wood to Cook and Stay Warm? People have burned wood for a very long time. They used it for cooking, for light, and for warmth. Wood holds energy from sunlight! https://socialmedia.xdme.com/tony/videos-book22/page-095.mp4 https://www.youtube.com/embed/ImM0DQTNbs4 113 2026-10-05T10:55:25+00:00 yes https://xdme.com/watch-book22-q096.html https://xdme.com/book22-thumbs/page-096.jpg How Can Rotting Food Scraps Make Fuel? Banana peels and leftover scraps usually end up as trash. But rotting food can be turned into fuel! Remember, methane is the main part of natural gas. https://socialmedia.xdme.com/tony/videos-book22/page-096.mp4 https://www.youtube.com/embed/7Lx-97YOZu0 115 2026-10-05T10:58:27+00:00 yes https://xdme.com/watch-book22-q097.html https://xdme.com/book22-thumbs/page-097.jpg How Can an Eel’s Body Make Electric Shocks? An electric eel can give a real jolt. It is not a magic power. It is a clever body made of tiny batteries! A big electric eel can make over six hundred volts. https://socialmedia.xdme.com/tony/videos-book22/page-097.mp4 https://www.youtube.com/embed/1I8kHfnLs-c 108 2026-10-05T11:01:30+00:00 yes https://xdme.com/watch-book22-q098.html https://xdme.com/book22-thumbs/page-098.jpg Why Can a Cheetah Sprint Fast but Not for Long? A cheetah is the fastest land animal on Earth. But it cannot run that fast for very long. Energy is the reason! A cheetah may need half an hour to recover after a sprint. https://socialmedia.xdme.com/tony/videos-book22/page-098.mp4 https://www.youtube.com/embed/48xQeiz3on4 111 2026-10-05T11:04:34+00:00 yes https://xdme.com/watch-book22-q099.html https://xdme.com/book22-thumbs/page-099.jpg Why Do Migrating Birds Eat So Much Before a Long Trip? Some birds fly across whole oceans without stopping to eat. That takes a lot of fuel. So they fill up before they go! Fat is the best fuel for long flights because it holds so much https://socialmedia.xdme.com/tony/videos-book22/page-099.mp4 https://www.youtube.com/embed/1ZQYPwCMtBs 117 2026-10-05T11:07:37+00:00 yes https://xdme.com/watch-book22-q100.html https://xdme.com/book22-thumbs/page-100.jpg How Do Deep-Sea Animals Get by with So Little Food? The deep ocean is dark and cold. No sunlight reaches it, so no plants grow. So how do animals down there get by? Some deep-sea fish have stomachs that stretch to hold meals larger https://socialmedia.xdme.com/tony/videos-book22/page-100.mp4 https://www.youtube.com/embed/sk2i0XOXkL0 116 2026-10-05T11:11:10+00:00 yes https://xdme.com/watch-book22-q101.html https://xdme.com/book22-thumbs/page-101.jpg How Does a Power Plant Make Electricity for a Whole Town? A power plant makes electricity for a whole town. The secret is a spinning machine. Remember, a big power plant can make enough electricity for hundreds of thousands of homes. https://socialmedia.xdme.com/tony/videos-book22/page-101.mp4 https://www.youtube.com/embed/S8iQPTSup70 115 2026-10-05T11:14:20+00:00 yes https://xdme.com/watch-book22-q102.html https://xdme.com/book22-thumbs/page-102.jpg What Is the Power Grid? Electricity travels a long way to reach your home. It rides along a giant network of wires. It is called the power grid! The North American power grid is one of the largest machine https://socialmedia.xdme.com/tony/videos-book22/page-102.mp4 https://www.youtube.com/embed/8_zlKt3mjXU 110 2026-10-05T11:17:22+00:00 yes https://xdme.com/watch-book22-q103.html https://xdme.com/book22-thumbs/page-103.jpg Why Do Long-Distance Power Lines Use Such High Voltage? Big power lines carry electricity over long distances. They use very high voltage to do it. Let's learn why! Some long power lines carry hundreds of thousands of volts. https://socialmedia.xdme.com/tony/videos-book22/page-103.mp4 https://www.youtube.com/embed/nK7W7uerbZM 114 2026-10-05T11:20:58+00:00 yes https://xdme.com/watch-book22-q104.html https://xdme.com/book22-thumbs/page-104.jpg Why Do Many Power Plants Burn Fuels Like Coal and Gas? Many power plants burn coal, oil, or natural gas. It is a simple way to get a lot of heat. But there are good and bad sides. Natural gas power plants can start up faster than many https://socialmedia.xdme.com/tony/videos-book22/page-104.mp4 https://www.youtube.com/embed/VUe80F0d4TA 110 2026-10-05T11:24:31+00:00 yes https://xdme.com/watch-book22-q105.html https://xdme.com/book22-thumbs/page-105.jpg What Makes an Energy Source Renewable? Some energy sources keep coming back. Others run out. What makes the difference? The Sun delivers about as much energy to Earth in one hour as people use in a year. https://socialmedia.xdme.com/tony/videos-book22/page-105.mp4 https://www.youtube.com/embed/8O8Sa4QFJZo 123 2026-10-05T11:28:04+00:00 yes https://xdme.com/watch-book22-q106.html https://xdme.com/book22-thumbs/page-106.jpg How Does a Wind Turbine Turn Wind Into Electricity? A giant wind turbine looks like a big pinwheel. It makes electricity from the wind. The tip of a big turbine blade can move over a hundred miles an hour, even though the blades loo https://socialmedia.xdme.com/tony/videos-book22/page-106.mp4 https://www.youtube.com/embed/5lNIVLmNavg 113 2026-10-05T11:31:07+00:00 yes https://xdme.com/watch-book22-q107.html https://xdme.com/book22-thumbs/page-107.jpg Why Do Wind Farms Put Their Turbines So High Up? Wind farms put their turbines way up high. They use tall towers and very long blades. There is a good reason! A single large turbine can power over a thousand homes. https://socialmedia.xdme.com/tony/videos-book22/page-107.mp4 https://www.youtube.com/embed/3y_tjyaYqAI 113 2026-10-05T11:34:09+00:00 yes https://xdme.com/watch-book22-q108.html https://xdme.com/book22-thumbs/page-108.jpg How Do Rooftop Solar Panels Share Power with the Grid? Solar panels on a roof can power a home. But that is not all they do. They can also share power with everyone else! Some homes get credit on their bills for the power they send out https://socialmedia.xdme.com/tony/videos-book22/page-108.mp4 https://www.youtube.com/embed/tH3uar6faI4 113 2026-10-05T11:37:43+00:00 yes https://xdme.com/watch-book22-q109.html https://xdme.com/book22-thumbs/page-109.jpg How Does a Tidal Power Station Use the Ocean? The ocean rises and falls twice every day. That is the tide, and it has a lot of energy. Remember, a tidal station in France has been making electricity since nineteen sixty-six. https://socialmedia.xdme.com/tony/videos-book22/page-109.mp4 https://www.youtube.com/embed/m7CGvc2gTUw 113 2026-10-05T11:41:17+00:00 yes https://xdme.com/watch-book22-q110.html https://xdme.com/book22-thumbs/page-110.jpg How Can Ocean Waves Make Electricity? Ocean waves never stop moving. That motion is energy. Can we turn it into electricity? Waves hold more energy during storms, but machines must survive them. https://socialmedia.xdme.com/tony/videos-book22/page-110.mp4 https://www.youtube.com/embed/3SyubWV_z2M 115 2026-10-05T11:44:20+00:00 yes https://xdme.com/watch-book22-q111.html https://xdme.com/book22-thumbs/page-111.jpg What Is Nuclear Energy, and How Does a Power Plant Use It? Nuclear power plants do not burn anything. They get their heat by splitting atoms. A tiny pellet of uranium fuel holds as much energy as a ton of coal. https://socialmedia.xdme.com/tony/videos-book22/page-111.mp4 https://www.youtube.com/embed/1unSrkSE-eY 118 2026-10-05T11:47:22+00:00 yes https://xdme.com/watch-book22-q112.html https://xdme.com/book22-thumbs/page-112.jpg What Happens to Solar and Wind Power When the Sun Sets or the Wind Stops? Solar panels make no power at night. Wind turbines slow down when the air is calm. So how do we keep the lights on? Wind is often stronger at night, while solar is strongest at noo https://socialmedia.xdme.com/tony/videos-book22/page-112.mp4 https://www.youtube.com/embed/dun_hCu9U6I 117 2026-10-05T11:50:57+00:00 yes https://xdme.com/watch-book22-q113.html https://xdme.com/book22-thumbs/page-113.jpg How Can We Store Extra Electricity? Electricity is very hard to store directly. So we change it into another form of energy. Then we change it back when we need it! The biggest batteries on grids can fill several foo https://socialmedia.xdme.com/tony/videos-book22/page-113.mp4 https://www.youtube.com/embed/nLlG1yVF_Bk 115 2026-10-05T11:54:10+00:00 yes https://xdme.com/watch-book22-q114.html https://xdme.com/book22-thumbs/page-114.jpg How Does Pumped Storage Work Like a Giant Water Battery? Imagine a giant battery made of water. It uses two lakes, one high and one low. That is pumped storage! Some pumped storage plants can run for many hours at a time. https://socialmedia.xdme.com/tony/videos-book22/page-114.mp4 https://www.youtube.com/embed/kJqrvvUfnPg 113 2026-10-05T11:57:13+00:00 yes https://xdme.com/watch-book22-q115.html https://xdme.com/book22-thumbs/page-115.jpg What Is a Kilowatt-Hour on an Electricity Bill? Your family's electricity bill has a strange unit on it. It says kilowatt-hours. Let's decode it! A kilowatt-hour is the same as three point six million joules. https://socialmedia.xdme.com/tony/videos-book22/page-115.mp4 https://www.youtube.com/embed/eSoC8tTWQCY 114 2026-10-05T12:00:47+00:00 yes https://xdme.com/watch-book22-q116.html https://xdme.com/book22-thumbs/page-116.jpg Why Does the Electricity in a Town Sometimes Go Out? Sometimes the lights go out all at once. It can feel a bit spooky. A closed fridge keeps food cold for several hours without power. https://socialmedia.xdme.com/tony/videos-book22/page-116.mp4 https://www.youtube.com/embed/IxXyDvi_jy0 117 2026-10-05T12:03:50+00:00 yes https://xdme.com/watch-book22-q117.html https://xdme.com/book22-thumbs/page-117.jpg How Do Solar Lamps and Small Grids Bring Light to Faraway Places? Some villages are far from any power line. Still, they can have light at night. A small solar lantern does the job! A good solar lantern can run for many hours on one day's charge. https://socialmedia.xdme.com/tony/videos-book22/page-117.mp4 https://www.youtube.com/embed/Cr3I7A5UIPc 111 2026-10-05T12:07:22+00:00 yes https://xdme.com/watch-book22-q118.html https://xdme.com/book22-thumbs/page-118.jpg How Is an Electric Car Charged, and Where Does That Energy Come From? An electric car has no gas tank. It runs on a big battery instead. But where does that energy come from? Electric cars can recover energy when braking. https://socialmedia.xdme.com/tony/videos-book22/page-118.mp4 https://www.youtube.com/embed/b3M8vdi2of0 115 2026-10-05T12:10:25+00:00 yes https://xdme.com/watch-book22-q119.html https://xdme.com/book22-thumbs/page-119.jpg Can Hydrogen Be a Clean Fuel? Hydrogen is a gas that can be a fuel. When it is used in a special device, the only leftover is water. Hydrogen is the most common element in the universe. https://socialmedia.xdme.com/tony/videos-book22/page-119.mp4 https://www.youtube.com/embed/ulkSPS3jyH0 113 2026-10-05T12:14:05+00:00 yes https://xdme.com/watch-book22-q120.html https://xdme.com/book22-thumbs/page-120.jpg How Much Electricity Can You Make by Pedaling? Could you power a light bulb with your own legs? A pedal generator can find out! It would take many people pedaling at once to power a toaster. https://socialmedia.xdme.com/tony/videos-book22/page-120.mp4 https://www.youtube.com/embed/5bnarhpHF6w 104 2026-10-05T12:17:09+00:00 yes https://xdme.com/watch-book22-q121.html https://xdme.com/book22-thumbs/page-121.jpg Why Do Solar Panels in Canada Face South? Rooftop solar panels in Canada usually face south. That is not random. It all comes from where the Sun is in the sky. In the summer, the Sun climbs higher, so a flatter panel works https://socialmedia.xdme.com/tony/videos-book22/page-121.mp4 https://www.youtube.com/embed/OZg9hHs0yB4 111 2026-10-05T12:20:10+00:00 yes https://xdme.com/watch-book22-q122.html https://xdme.com/book22-thumbs/page-122.jpg What Is That Gray Can on the Power Pole? Have you ever noticed a gray can on a power pole? It is not a trash can or a light. It does a very important job! A transformer has no moving parts. https://socialmedia.xdme.com/tony/videos-book22/page-122.mp4 https://www.youtube.com/embed/vpzS7v2Uwak 110 2026-10-05T12:24:26+00:00 yes https://xdme.com/watch-book22-q123.html https://xdme.com/book22-thumbs/page-123.jpg Why Do Some Power Plants Have Giant Cooling Towers? Some power plants have giant towers that look like huge vases. White clouds float up out of them. What are those towers doing? Cooling towers can be taller than a thirty-story buil https://socialmedia.xdme.com/tony/videos-book22/page-123.mp4 https://www.youtube.com/embed/cdWjmDPC4D0 108 2026-10-05T12:27:37+00:00 yes https://xdme.com/watch-book22-q124.html https://xdme.com/book22-thumbs/page-124.jpg Why Does Electricity Use Go Up in the Evening? Every evening, people all come home at the same time. They flip on lights, cook dinner, and watch TV. That makes electricity use shoot up! https://socialmedia.xdme.com/tony/videos-book22/page-124.mp4 https://www.youtube.com/embed/Y8wiICca0WE 115 2026-10-05T12:31:13+00:00 yes https://xdme.com/watch-book22-q125.html https://xdme.com/book22-thumbs/page-125.jpg What Is the Trade-Off with Each Energy Source? Every energy source has good points. And every one has challenges too. Let's weigh them! No energy source is perfect, so engineers look for balance. https://socialmedia.xdme.com/tony/videos-book22/page-125.mp4 https://www.youtube.com/embed/xpF2wNUk8D8 115 2026-10-05T12:34:18+00:00 yes https://xdme.com/watch-book22-q126.html https://xdme.com/book22-thumbs/page-126.jpg What Does Energy Efficiency Mean? Two light bulbs can glow just as bright. But one can use much less electricity. That is called energy efficiency! An LED bulb can use about one-sixth the electricity of an old-styl https://socialmedia.xdme.com/tony/videos-book22/page-126.mp4 https://www.youtube.com/embed/rheMdvvOA68 113 2026-10-05T12:37:52+00:00 yes https://xdme.com/watch-book22-q127.html https://xdme.com/book22-thumbs/page-127.jpg What Do Energy Star and EnerGuide Labels Tell Us? Fridges and washers often wear special labels. These labels tell you how much energy a machine uses. Let's learn to read them! Washing machines have become far more efficient than https://socialmedia.xdme.com/tony/videos-book22/page-127.mp4 https://www.youtube.com/embed/vovoReOftlk 112 2026-10-05T12:40:54+00:00 yes https://xdme.com/watch-book22-q128.html https://xdme.com/book22-thumbs/page-128.jpg Why Do Some Devices Use Power Even When They Are Turned Off? Your TV looks like it is off. But a tiny red light is still glowing. Is it still using power? Standby power can add up to a noticeable share of a home's electricity use. https://socialmedia.xdme.com/tony/videos-book22/page-128.mp4 https://www.youtube.com/embed/wNmZH9AP8aU 112 2026-10-05T12:43:56+00:00 yes https://xdme.com/watch-book22-q129.html https://xdme.com/book22-thumbs/page-129.jpg Why Do Windows Let So Much Heat Escape in Winter? In winter, warmth tries to sneak out of your house. Windows are one of its favorite exits. Triple-pane windows are common in very cold places. https://socialmedia.xdme.com/tony/videos-book22/page-129.mp4 https://www.youtube.com/embed/rI7hIQNTX9U 113 2026-10-05T12:47:29+00:00 yes https://xdme.com/watch-book22-q130.html https://xdme.com/book22-thumbs/page-130.jpg How Does Insulation Keep a House Cozy? A cozy house in winter needs a warm blanket in the walls. It is made of tiny pockets of trapped air. It is called insulation! A wool sweater works like insulation for your body. https://socialmedia.xdme.com/tony/videos-book22/page-130.mp4 https://www.youtube.com/embed/MZMs2RWQ7cU 117 2026-10-05T12:51:01+00:00 yes https://xdme.com/watch-book22-q131.html https://xdme.com/book22-thumbs/page-131.jpg How Does a Thermostat Know When to Turn the Heat On? A thermostat is like a little brain for your heating. It keeps your home at just the right temperature. How does it know when to switch on? https://socialmedia.xdme.com/tony/videos-book22/page-131.mp4 https://www.youtube.com/embed/PSCqrc_ZfSc 107 2026-10-05T12:54:34+00:00 yes https://xdme.com/watch-book22-q132.html https://xdme.com/book22-thumbs/page-132.jpg How Does a Heat Pump Move Heat Instead of Making It? A heat pump does not make heat. It moves heat from one place to another. That is a clever trick! A heat pump can warm a home even when it is well below freezing outside. https://socialmedia.xdme.com/tony/videos-book22/page-132.mp4 https://www.youtube.com/embed/1f-q1DraRu0 107 2026-10-05T12:58:07+00:00 yes https://xdme.com/watch-book22-q133.html https://xdme.com/book22-thumbs/page-133.jpg Why Does Hanging Laundry Outside Save Energy? A clothes dryer uses a lot of energy. A clothesline uses almost none at all. The Sun and the wind do the work! Dryers are one of the biggest energy users among household appliances https://socialmedia.xdme.com/tony/videos-book22/page-133.mp4 https://www.youtube.com/embed/L4KCc71IDcA 112 2026-10-05T13:01:45+00:00 yes https://xdme.com/watch-book22-q134.html https://xdme.com/book22-thumbs/page-134.jpg What Happens If the Fridge Door Stays Open? What if the fridge door stays open? Cold air rushes out into the kitchen. A fridge's door seal is a strip of magnets that holds it tightly closed. https://socialmedia.xdme.com/tony/videos-book22/page-134.mp4 https://www.youtube.com/embed/lj0L-wd3SKQ 108 2026-10-05T13:05:49+00:00 yes https://xdme.com/watch-book22-q135.html https://xdme.com/book22-thumbs/page-135.jpg Why Does Putting a Lid on a Pot Save Energy? Cooking with the lid off lets heat slip away. Putting the lid on is an easy energy saver. Here is why! A pressure cooker uses a tight lid to cook food faster. https://socialmedia.xdme.com/tony/videos-book22/page-135.mp4 https://www.youtube.com/embed/UAKT0afmGBQ 110 2026-10-05T13:09:21+00:00 yes https://xdme.com/watch-book22-q136.html https://xdme.com/book22-thumbs/page-136.jpg Does Taking a Shorter Shower Really Save Energy? A shower feels wonderful on a cold morning. But heating all that water takes lots of energy. So does a shorter shower really help? https://socialmedia.xdme.com/tony/videos-book22/page-136.mp4 https://www.youtube.com/embed/GDma1MomViA 113 2026-10-05T13:16:02+00:00 yes https://xdme.com/watch-book22-q137.html https://xdme.com/book22-thumbs/page-137.jpg How Can Trees Around a House Save Energy? Trees can work like free air conditioners for a house. They also block cold winter wind. The right tree in the right place makes a big difference! https://socialmedia.xdme.com/tony/videos-book22/page-137.mp4 https://www.youtube.com/embed/R5O5WaHUn38 110 2026-10-05T13:19:05+00:00 yes https://xdme.com/watch-book22-q138.html https://xdme.com/book22-thumbs/page-138.jpg What Is Passive Solar Design? Some buildings are designed to catch the Sun's free heat. They do it with no machines at all. That is called passive solar design! https://socialmedia.xdme.com/tony/videos-book22/page-138.mp4 https://www.youtube.com/embed/HBa3x79uLBs 114 2026-10-05T13:22:39+00:00 yes https://xdme.com/watch-book22-q139.html https://xdme.com/book22-thumbs/page-139.jpg Is Biking More Energy-Efficient than Driving? A person on a bike zooms along using only muscles. A car burns lots of fuel to go the same distance. Which one is more efficient? A bicycle is often called the most efficient way p https://socialmedia.xdme.com/tony/videos-book22/page-139.mp4 https://www.youtube.com/embed/CO9ImIFbKtA 109 2026-10-05T13:25:41+00:00 yes https://xdme.com/watch-book22-q140.html https://xdme.com/book22-thumbs/page-140.jpg How Can You Find Drafts in Your Home? Drafts are sneaky little leaks of air in your home. Cold air gets in and warm air gets out. Let's go find them! Remember, even small cracks can add up to the size of an open window https://socialmedia.xdme.com/tony/videos-book22/page-140.mp4 https://www.youtube.com/embed/HpH_vyx0kMA 108 2026-10-05T13:29:16+00:00 yes https://xdme.com/watch-book22-q141.html https://xdme.com/book22-thumbs/page-141.jpg Which Energy-Saving Habits Matter Most? Some energy-saving habits save more than others. Little choices can add up! Remember, switching to LED bulbs is one of the easiest savings. https://socialmedia.xdme.com/tony/videos-book22/page-141.mp4 https://www.youtube.com/embed/MG5rr-3MiFE 119 2026-10-05T13:32:49+00:00 yes https://xdme.com/watch-book22-q142.html https://xdme.com/book22-thumbs/page-142.jpg How Do Motion-Sensor Lights Save Energy? Some lights switch on all by themselves when you walk by. They are called motion-sensor lights. How do they know you are there? Some sensors can tell when a room is empty and switc https://socialmedia.xdme.com/tony/videos-book22/page-142.mp4 https://www.youtube.com/embed/SZ_wx6glNQE 112 2026-10-05T13:36:24+00:00 yes https://xdme.com/watch-book22-q143.html https://xdme.com/book22-thumbs/page-143.jpg Why Does a Phone Charger Feel Warm? Touch a phone charger, and it feels a bit warm. That warmth tells a secret. Some energy is escaping! More efficient chargers waste less heat. https://socialmedia.xdme.com/tony/videos-book22/page-143.mp4 https://www.youtube.com/embed/bD9OLq47Reg 109 2026-10-05T13:39:56+00:00 yes https://xdme.com/watch-book22-q144.html https://xdme.com/book22-thumbs/page-144.jpg Why Does Recycling an Aluminum Can Save Energy? A used soda can goes in the recycling bin. That little act saves a surprising amount of energy. The energy saved by recycling one can could run a TV for a few hours. https://socialmedia.xdme.com/tony/videos-book22/page-144.mp4 https://www.youtube.com/embed/3EklN4i1fsE 113 2026-10-05T13:43:00+00:00 yes https://xdme.com/watch-book22-q145.html https://xdme.com/book22-thumbs/page-145.jpg What New Energy Ideas Are Scientists Testing? Scientists and engineers never stop testing new ideas. Some might power our world someday. Let's peek into the lab! Remember, some experimental solar cells are thin and bendy like https://socialmedia.xdme.com/tony/videos-book22/page-145.mp4 https://www.youtube.com/embed/HXduHhf21G4 117 2026-10-05T13:46:34+00:00 yes https://xdme.com/watch-book22-q146.html https://xdme.com/book22-thumbs/page-146.jpg How Can Your Class Run an Energy-Saving Project? Your class can become a team of energy detectives. You can find wasted energy at school. And then you can fix it! Many schools have saved real money with student energy teams. https://socialmedia.xdme.com/tony/videos-book22/page-146.mp4 https://www.youtube.com/embed/tt09gGu0MMI 112 2026-10-05T13:50:37+00:00 yes https://xdme.com/watch-book22-q147.html https://xdme.com/book22-thumbs/page-147.jpg Can Footsteps on a Special Floor Make Electricity? Could your footsteps make electricity? Special floor tiles say yes, a little. Let's step into the idea! Floor tiles like these have been tested in train stations and playgrounds. https://socialmedia.xdme.com/tony/videos-book22/page-147.mp4 https://www.youtube.com/embed/HoHhwqPTg4s 112 2026-10-05T13:54:10+00:00 yes https://xdme.com/watch-book22-q148.html https://xdme.com/book22-thumbs/page-148.jpg Which Things in a Home Use the Most Energy? Your home uses energy in many ways. Some things use much more than others. Which ones are the big users? A fridge runs all day and night, so it uses lots of energy over a year. https://socialmedia.xdme.com/tony/videos-book22/page-148.mp4 https://www.youtube.com/embed/O9Xwc-Q10ik 113 2026-10-05T13:57:43+00:00 yes https://xdme.com/watch-book22-q149.html https://xdme.com/book22-thumbs/page-149.jpg Why Do Small Energy Savings Add Up? One light turned off saves only a little. But little savings can add up to big ones. If every home switched off one unused light for an hour, a whole city would save a lot of power https://socialmedia.xdme.com/tony/videos-book22/page-149.mp4 https://www.youtube.com/embed/EJgwg-buC5M 109 2026-10-05T18:20:29+00:00 yes https://xdme.com/watch-book22-q150.html https://xdme.com/book22-thumbs/page-150.jpg What Are the Big Ideas to Remember About Energy? We have explored energy in so many ways. Let's gather the big ideas to remember. Then you can go be an energy detective! Energy is what makes everything happen. https://socialmedia.xdme.com/tony/videos-book22/page-150.mp4 https://www.youtube.com/embed/ZuB00r6Sqrg 119 2026-10-05T18:24:05+00:00 yes https://xdme.com/watch-book23-q001.html https://xdme.com/book23-thumbs/page-001.jpg What Are the Four Forces of Flight? Every flying thing is balanced by four forces. Lift, weight, thrust, and drag all push and pull at once. Birds, bees, and kites follow the same four rules! https://socialmedia.xdme.com/tony/videos-book23/page-001.mp4 https://www.youtube.com/embed/nMf7PcWmNnI 111 2026-10-05T19:11:34+00:00 yes https://xdme.com/watch-book23-q002.html https://xdme.com/book23-thumbs/page-002.jpg What Is Lift, and Where Does It Come From? Lift is the upward push on a wing. Without it, nothing heavier than air could fly. Where does it come from? A jumbo jet's wings make enough lift to hold up hundreds of tons. https://socialmedia.xdme.com/tony/videos-book23/page-002.mp4 https://www.youtube.com/embed/0YfrEQvCJ70 106 2026-10-05T19:11:36+00:00 yes https://xdme.com/watch-book23-q003.html https://xdme.com/book23-thumbs/page-003.jpg How Does the Shape of a Wing Help It Climb? A wing is not just a flat board. Its special shape helps it climb into the sky. The shape is called an airfoil! A paper plane with a flat wing can still fly because it tilts up sli https://socialmedia.xdme.com/tony/videos-book23/page-003.mp4 https://www.youtube.com/embed/I2kxs8kprhw 107 2026-10-05T19:11:39+00:00 yes https://xdme.com/watch-book23-q004.html https://xdme.com/book23-thumbs/page-004.jpg What Is Thrust, and How Do Planes Get It? Thrust is the force that moves a plane forward. Without it, a plane would just sit on the runway. How do planes get it? Some small planes are powered by electric motors. https://socialmedia.xdme.com/tony/videos-book23/page-004.mp4 https://www.youtube.com/embed/NAkmfAWzQHE 109 2026-10-05T19:11:40+00:00 yes https://xdme.com/watch-book23-q005.html https://xdme.com/book23-thumbs/page-005.jpg What Is Drag, the Force That Slows Things Down? Drag is the force that slows things down. You feel it when you push against a strong wind. Let's learn how to beat it! Doubling your speed makes drag about four times larger. https://socialmedia.xdme.com/tony/videos-book23/page-005.mp4 https://www.youtube.com/embed/TvCv3OpPy1o 109 2026-10-05T19:11:41+00:00 yes https://xdme.com/watch-book23-q006.html https://xdme.com/book23-thumbs/page-006.jpg How Does Weight Pull on Every Flyer? Weight is Earth's gravity pulling on everything. Even things that fly must deal with it. A hummingbird weighs less than a nickel coin. https://socialmedia.xdme.com/tony/videos-book23/page-006.mp4 https://www.youtube.com/embed/lt3u-VEL4cA 108 2026-10-05T19:11:42+00:00 yes https://xdme.com/watch-book23-q007.html https://xdme.com/book23-thumbs/page-007.jpg What Is the Angle of Attack? A wing can be tilted up a little compared with the air. That tilt is called the angle of attack. It changes how much lift you get! https://socialmedia.xdme.com/tony/videos-book23/page-007.mp4 https://www.youtube.com/embed/P_hGm3h2kJg 107 2026-10-05T19:11:44+00:00 yes https://xdme.com/watch-book23-q008.html https://xdme.com/book23-thumbs/page-008.jpg What Is a Stall, and How Do Pilots Handle It? A stall sounds scary. But it has nothing to do with the engine stopping. Pilots know exactly what to do! Birds also stall when they land, and they use it to slow down. https://socialmedia.xdme.com/tony/videos-book23/page-008.mp4 https://www.youtube.com/embed/kzuvbHNdOIg 106 2026-10-05T19:11:45+00:00 yes https://xdme.com/watch-book23-q009.html https://xdme.com/book23-thumbs/page-009.jpg Why Do Planes Need to Go Fast Before They Can Take Off? A plane cannot just jump into the sky. It has to roll down the runway first. It needs to get going fast! A big jet may use more than two miles of runway on a hot, heavy day. https://socialmedia.xdme.com/tony/videos-book23/page-009.mp4 https://www.youtube.com/embed/LTnOU-e-i-A 107 2026-10-05T19:11:46+00:00 yes https://xdme.com/watch-book23-q010.html https://xdme.com/book23-thumbs/page-010.jpg Why Do Airplanes Take Off Facing Into the Wind? Pilots love taking off and landing into the wind. It might seem backward. But wind helps a plane fly! Airport wind socks show pilots which way the wind is blowing. https://socialmedia.xdme.com/tony/videos-book23/page-010.mp4 https://www.youtube.com/embed/Ik8PvHD53PQ 109 2026-10-05T19:11:47+00:00 yes https://xdme.com/watch-book23-q011.html https://xdme.com/book23-thumbs/page-011.jpg Does a Wing Really Push Air Downward to Go Up? Does a wing really push air downward to go up? Yes, it does! It all comes down to a famous rule of science. A helicopter hovering above water makes a spray of downward-blown air. https://socialmedia.xdme.com/tony/videos-book23/page-011.mp4 https://www.youtube.com/embed/DVFTBj9qkAY 107 2026-10-05T19:11:49+00:00 yes https://xdme.com/watch-book23-q012.html https://xdme.com/book23-thumbs/page-012.jpg How Are Lift and Weight Balanced in Level Flight? When a plane flies straight and level, all the forces balance. Lift matches weight, and thrust matches drag. But the balance keeps changing a little! https://socialmedia.xdme.com/tony/videos-book23/page-012.mp4 https://www.youtube.com/embed/O91XDcVIQEk 108 2026-10-05T19:11:51+00:00 yes https://xdme.com/watch-book23-q013.html https://xdme.com/book23-thumbs/page-013.jpg What Happens to the Four Forces During Takeoff, Cruising, and Landing? A flight has three big parts. Take-off, cruising, and landing. The four forces change in each one! A landing jet touches down at about one hundred fifty miles per hour. https://socialmedia.xdme.com/tony/videos-book23/page-013.mp4 https://www.youtube.com/embed/X1sQF9fciDs 116 2026-10-05T19:11:52+00:00 yes https://xdme.com/watch-book23-q014.html https://xdme.com/book23-thumbs/page-014.jpg How Do Ailerons Help a Plane Roll and Turn? A plane can roll to the left or right in the sky. Little flaps on the wings make that happen. They are called ailerons! Ailerons always move in opposite directions on the two wings https://socialmedia.xdme.com/tony/videos-book23/page-014.mp4 https://www.youtube.com/embed/NMxfQeHlxgk 108 2026-10-05T19:11:54+00:00 yes https://xdme.com/watch-book23-q015.html https://xdme.com/book23-thumbs/page-015.jpg What Do the Rudder and Elevator at the Tail Do? The tail of a plane is not just for looks. It has two important controls. Each one steers in a different direction! Many small planes have rudder pedals that pilots push with their https://socialmedia.xdme.com/tony/videos-book23/page-015.mp4 https://www.youtube.com/embed/TgMZTlEiiuU 107 2026-10-05T19:11:55+00:00 yes https://xdme.com/watch-book23-q016.html https://xdme.com/book23-thumbs/page-016.jpg What Are Pitch, Roll, and Yaw? A plane can turn in three different ways. They have funny names. Pitch, roll, and yaw! Drones and spacecraft also use pitch, roll, and yaw. https://socialmedia.xdme.com/tony/videos-book23/page-016.mp4 https://www.youtube.com/embed/Q4-i9eU34YI 106 2026-10-05T19:14:06+00:00 yes https://xdme.com/watch-book23-q017.html https://xdme.com/book23-thumbs/page-017.jpg Why Does a Plane Tilt to the Side When It Turns? Have you noticed a plane tilts when it turns? It leans into the curve like a bike rider. There is a good reason! Passengers usually feel only a gentle push into their seats during https://socialmedia.xdme.com/tony/videos-book23/page-017.mp4 https://www.youtube.com/embed/izjstkS7PBQ 108 2026-10-05T19:16:39+00:00 yes https://xdme.com/watch-book23-q018.html https://xdme.com/book23-thumbs/page-018.jpg Why Do Some Planes Have Curved-Up Wingtips? Look closely at some airliners' wingtips. They curve up into little fins. They are called winglets! Winglets can save airlines millions of gallons of fuel a year. https://socialmedia.xdme.com/tony/videos-book23/page-018.mp4 https://www.youtube.com/embed/PJElC5l_MYk 115 2026-10-05T19:20:28+00:00 yes https://xdme.com/watch-book23-q019.html https://xdme.com/book23-thumbs/page-019.jpg Why Do Big, Heavy Flyers Need Big Wings? Heavy flyers need big wings. A swan has much larger wings than a sparrow. Lift depends on wing area! The largest flying bird alive by wingspan is the wandering albatross, with wing https://socialmedia.xdme.com/tony/videos-book23/page-019.mp4 https://www.youtube.com/embed/f8u3Lgn_ySQ 112 2026-10-05T19:22:59+00:00 yes https://xdme.com/watch-book23-q020.html https://xdme.com/book23-thumbs/page-020.jpg Can a Plane Fly Upside Down? Can a plane fly upside down? You might think it could not. But stunt pilots do it all the time! Some stunt planes roll all the way around in about a second. https://socialmedia.xdme.com/tony/videos-book23/page-020.mp4 https://www.youtube.com/embed/qLQUJQ1SfuU 112 2026-10-05T19:26:33+00:00 yes https://xdme.com/watch-book23-q021.html https://xdme.com/book23-thumbs/page-021.jpg Why Do Jets Cruise So High Up Where the Air Is Thin? Jets cruise way up high, where the air is thin. They fly higher than most clouds. It is a smart place to fly! Outside a jet at cruising height, the air temperature is around minus https://socialmedia.xdme.com/tony/videos-book23/page-021.mp4 https://www.youtube.com/embed/IOa_gHdrVpc 114 2026-10-05T19:29:12+00:00 yes https://xdme.com/watch-book23-q022.html https://xdme.com/book23-thumbs/page-022.jpg How Do Wind Tunnels Help Engineers Test Wings? How do engineers test new wings before building a plane? They use a giant tube with a fan. It is called a wind tunnel! Some wind tunnels are big enough to hold a whole real airplan https://socialmedia.xdme.com/tony/videos-book23/page-022.mp4 https://www.youtube.com/embed/0yTo9XO45qQ 108 2026-10-05T19:32:16+00:00 yes https://xdme.com/watch-book23-q023.html https://xdme.com/book23-thumbs/page-023.jpg Why Do Airplane Wings Bend Upward in Flight? In flight, an airplane's wings bend upward. It might look scary, but it is by design. Wings are made to flex! Engineers bend test wings far beyond anything flight would ever ask of https://socialmedia.xdme.com/tony/videos-book23/page-023.mp4 https://www.youtube.com/embed/lZ3NwJ5FCvA 110 2026-10-05T19:35:21+00:00 yes https://xdme.com/watch-book23-q024.html https://xdme.com/book23-thumbs/page-024.jpg What Did the Wright Brothers Discover About Flight? Orville and Wilbur Wright were bicycle makers. They had a big dream about flying. And they made it happen! The first flight was shorter than the wingspan of a modern jumbo jet. https://socialmedia.xdme.com/tony/videos-book23/page-024.mp4 https://www.youtube.com/embed/scRhXLQun7o 112 2026-10-05T19:38:24+00:00 yes https://xdme.com/watch-book23-q025.html https://xdme.com/book23-thumbs/page-025.jpg How Do the Four Forces Explain a Bird, a Plane, and a Kite? A bird, a plane, and a kite all stay in the air. They look so different. But the same four forces explain them all! Even a falling maple seed spins to make its own lift. https://socialmedia.xdme.com/tony/videos-book23/page-025.mp4 https://www.youtube.com/embed/ushNXbZuKrI 106 2026-10-05T19:40:56+00:00 yes https://xdme.com/watch-book23-q026.html https://xdme.com/book23-thumbs/page-026.jpg How Do Feathers Turn a Bird's Wing Into a Flying Machine? A bird's wing is covered in feathers. They turn a wing into a flying machine. A bird's flight feathers can be replaced one at a time as they wear out. https://socialmedia.xdme.com/tony/videos-book23/page-026.mp4 https://www.youtube.com/embed/oiWMnGxIN5k 113 2026-10-05T19:44:31+00:00 yes https://xdme.com/watch-book23-q027.html https://xdme.com/book23-thumbs/page-027.jpg Why Do Some Birds Flap Constantly While Others Soar? Some birds flap and flap. Others glide for hours on still wings. What makes the difference? Some seabirds can go for hours without flapping once they are up in the air. https://socialmedia.xdme.com/tony/videos-book23/page-027.mp4 https://www.youtube.com/embed/RvAZq26S56k 113 2026-10-05T19:47:02+00:00 yes https://xdme.com/watch-book23-q028.html https://xdme.com/book23-thumbs/page-028.jpg How Do Light, Hollow Bones Help Birds Fly? Birds need to be light to fly. Many of their bones are hollow! Even though they are hollow, some bird bones are stronger for their weight than bones in most mammals. https://socialmedia.xdme.com/tony/videos-book23/page-028.mp4 https://www.youtube.com/embed/-uXT56IKRxc 109 2026-10-05T19:50:06+00:00 yes https://xdme.com/watch-book23-q029.html https://xdme.com/book23-thumbs/page-029.jpg How Do Birds Land So Gracefully? Birds land on a tiny branch with perfect balance. It looks so easy. But it takes real skill! A good landing is a skill that young birds learn by practice. https://socialmedia.xdme.com/tony/videos-book23/page-029.mp4 https://www.youtube.com/embed/eVPainpvvjo 111 2026-10-05T19:53:08+00:00 yes https://xdme.com/watch-book23-q030.html https://xdme.com/book23-thumbs/page-030.jpg What Do a Bird's Tail Feathers Do in the Air? A bird's tail is like a steering wheel with feathers. It acts like a rudder and an elevator at once. A peacock's long tail is for show and does not help it fly. https://socialmedia.xdme.com/tony/videos-book23/page-030.mp4 https://www.youtube.com/embed/hgN4rZxa_d8 107 2026-10-05T19:55:49+00:00 yes https://xdme.com/watch-book23-q031.html https://xdme.com/book23-thumbs/page-031.jpg How Does a Heavy Swan Get Off the Water and Into the Air? A swan is one of the heaviest flying birds. Getting into the air is a big job for it. It needs a long running start! A mute swan can weigh as much as a small dog. https://socialmedia.xdme.com/tony/videos-book23/page-031.mp4 https://www.youtube.com/embed/9o731d3fSwo 106 2026-10-05T19:59:22+00:00 yes https://xdme.com/watch-book23-q032.html https://xdme.com/book23-thumbs/page-032.jpg What Is a Thermal, and How Do Hawks Ride One? Hawks and vultures circle high in the sky without flapping. They are riding invisible elevators. They are called thermals! Gliders and hang-glider pilots also use thermals. https://socialmedia.xdme.com/tony/videos-book23/page-032.mp4 https://www.youtube.com/embed/ux3xDPcmfWU 108 2026-10-05T20:01:55+00:00 yes https://xdme.com/watch-book23-q033.html https://xdme.com/book23-thumbs/page-033.jpg How Can an Albatross Cross an Ocean with Hardly Any Flapping? An albatross can cross an entire ocean. It hardly flaps its wings at all. It uses a clever wind trick! Some albatrosses spend years at sea without touching land. https://socialmedia.xdme.com/tony/videos-book23/page-033.mp4 https://www.youtube.com/embed/L8gANSvRiXw 115 2026-10-05T20:05:29+00:00 yes https://xdme.com/watch-book23-q034.html https://xdme.com/book23-thumbs/page-034.jpg Why Can Ostriches and Penguins Not Fly? Ostriches and penguins are birds. But neither one can fly. Why not? An ostrich can run about forty-five miles per hour. Penguin wings work like flippers. https://socialmedia.xdme.com/tony/videos-book23/page-034.mp4 https://www.youtube.com/embed/12BprGK2aas 117 2026-10-05T20:08:36+00:00 yes https://xdme.com/watch-book23-q035.html https://xdme.com/book23-thumbs/page-035.jpg How Can an Insect Beat Its Wings Hundreds of Times Each Second? A honeybee beats its wings hundreds of times each second. How can any muscle move so fast? The secret is in the muscles! A hummingbird's wings beat about fifty times a second, much https://socialmedia.xdme.com/tony/videos-book23/page-035.mp4 https://www.youtube.com/embed/MYvV-2W2lUo 113 2026-10-05T20:11:51+00:00 yes https://xdme.com/watch-book23-q036.html https://xdme.com/book23-thumbs/page-036.jpg How Does an Insect's Chest Work Like a Wing-Wiggling Box? Here is a surprise about insect wings. The muscles that move them are not in the wings. They are in the chest! A fly's thorax is like a springy box that helps save energy as it fla https://socialmedia.xdme.com/tony/videos-book23/page-036.mp4 https://www.youtube.com/embed/gVDt5ktI6HU 107 2026-10-05T20:14:21+00:00 yes https://xdme.com/watch-book23-q037.html https://xdme.com/book23-thumbs/page-037.jpg How Do Bumblebees Fly When People Once Said They Could Not? There is an old story about bumblebees. It says scientists once decided they could not fly. But bees fly just fine! A bumblebee flaps its wings about two hundred times a second. https://socialmedia.xdme.com/tony/videos-book23/page-037.mp4 https://www.youtube.com/embed/HKWh4fTFGOI 113 2026-10-05T20:16:58+00:00 yes https://xdme.com/watch-book23-q038.html https://xdme.com/book23-thumbs/page-038.jpg How Is a Bat's Wing Different From a Bird's Wing? A bat's wing is very different from a bird's wing. It has no feathers at all. It is made of stretchy skin! There are more than fourteen hundred kinds of bats. https://socialmedia.xdme.com/tony/videos-book23/page-038.mp4 https://www.youtube.com/embed/aVlwju5s-Is 108 2026-10-05T20:19:29+00:00 yes https://xdme.com/watch-book23-q039.html https://xdme.com/book23-thumbs/page-039.jpg What Is the Difference Between Flying and Gliding for an Animal? Some animals fly and some animals glide. They are not the same thing. Some gliding frogs have webbed feet that act as parachutes. Flying squirrels only glide. https://socialmedia.xdme.com/tony/videos-book23/page-039.mp4 https://www.youtube.com/embed/21DHDgnHb-w 115 2026-10-05T20:22:34+00:00 yes https://xdme.com/watch-book23-q040.html https://xdme.com/book23-thumbs/page-040.jpg Can Snakes and Frogs Glide Through the Air? Snakes and frogs can glide through the air! It sounds like a tall tale. But it is true! A flying snake can glide the length of a tennis court or more. https://socialmedia.xdme.com/tony/videos-book23/page-040.mp4 https://www.youtube.com/embed/zaI-xOeo5H0 111 2026-10-05T20:25:07+00:00 yes https://xdme.com/watch-book23-q041.html https://xdme.com/book23-thumbs/page-041.jpg How Do Dandelion Seeds Sail on a Breath of Wind? A dandelion seed sails away on a puff of wind. It looks like a tiny parachute. Dandelion seeds can travel more than a mile on the wind. https://socialmedia.xdme.com/tony/videos-book23/page-041.mp4 https://www.youtube.com/embed/sV1HCWQ1Jjs 108 2026-10-05T20:27:38+00:00 yes https://xdme.com/watch-book23-q042.html https://xdme.com/book23-thumbs/page-042.jpg How Do Baby Birds Learn to Fly? Baby birds are born without the ability to fly. They have to learn. Let's watch how they do it! A baby bird's first flight might last only a few seconds. https://socialmedia.xdme.com/tony/videos-book23/page-042.mp4 https://www.youtube.com/embed/3hl01WxWSTE 109 2026-10-05T20:30:39+00:00 yes https://xdme.com/watch-book23-q043.html https://xdme.com/book23-thumbs/page-043.jpg Can Any Bird Sleep While Flying? Could a bird sleep while it is flying? It sounds impossible. But some birds can do it! Common swifts can stay in the air for many months without landing. https://socialmedia.xdme.com/tony/videos-book23/page-043.mp4 https://www.youtube.com/embed/1liEpa4_NcE 110 2026-10-05T20:33:11+00:00 yes https://xdme.com/watch-book23-q044.html https://xdme.com/book23-thumbs/page-044.jpg How Does a Feather Stay Light, Strong, and Smooth? A feather is light, strong, and smooth all at once. How does it do that? It zips itself together! A bird can have thousands of feathers on its body. https://socialmedia.xdme.com/tony/videos-book23/page-044.mp4 https://www.youtube.com/embed/1vFKnEUV0lw 114 2026-10-05T20:35:43+00:00 yes https://xdme.com/watch-book23-q045.html https://xdme.com/book23-thumbs/page-045.jpg How Far Can a Bird Fly Without Stopping? Which bird can fly the farthest without stopping? The record is almost unbelievable. It belongs to a bird called the bar-tailed godwit! https://socialmedia.xdme.com/tony/videos-book23/page-045.mp4 https://www.youtube.com/embed/T1qg-2bPs40 115 2026-10-05T20:38:44+00:00 yes https://xdme.com/watch-book23-q046.html https://xdme.com/book23-thumbs/page-046.jpg How Do Birds Change the Shape of Their Wings? A bird can change the shape of its wings in the air. It can bend, fold, and fan them. That gives it amazing control! Eagles spread the feathers at their wingtips like fingers when https://socialmedia.xdme.com/tony/videos-book23/page-046.mp4 https://www.youtube.com/embed/AUzGiLvESz4 105 2026-10-05T20:41:15+00:00 yes https://xdme.com/watch-book23-q047.html https://xdme.com/book23-thumbs/page-047.jpg Why Do Some Birds Have Long, Pointed Wings and Others Short, Round Ones? Some birds have long, pointed wings. Others have short, round ones. Each shape fits a way of life! Birds that live in thick forests often have shorter wings than those in open sky. https://socialmedia.xdme.com/tony/videos-book23/page-047.mp4 https://www.youtube.com/embed/aG2tb4ESf2o 114 2026-10-05T20:44:17+00:00 yes https://xdme.com/watch-book23-q048.html https://xdme.com/book23-thumbs/page-048.jpg How Do Baby Spiders Fly on Silk Threads? Baby spiders can fly! They do it without any wings. They use silk threads! Charles Darwin noticed spiders landing on his ship while it was far from land. https://socialmedia.xdme.com/tony/videos-book23/page-048.mp4 https://www.youtube.com/embed/FiZsyvqFTQE 106 2026-10-05T20:46:48+00:00 yes https://xdme.com/watch-book23-q049.html https://xdme.com/book23-thumbs/page-049.jpg Why Can't People Fly by Flapping Wings Tied to Their Arms? Why can't people flap wings tied to their arms and fly? Birds do it all the time. The answer is in the muscles! Pedal-powered aircraft have crossed the English Channel, but they ne https://socialmedia.xdme.com/tony/videos-book23/page-049.mp4 https://www.youtube.com/embed/XU8XE8Pj8TY 114 2026-10-05T20:49:30+00:00 yes https://xdme.com/watch-book23-q050.html https://xdme.com/book23-thumbs/page-050.jpg What Can Engineers Learn From Flying Animals? Flying animals have had millions of years to practice. Engineers watch and learn from them. Nature is a great teacher! The shape of some fast trains copies a kingfisher's beak. https://socialmedia.xdme.com/tony/videos-book23/page-050.mp4 https://www.youtube.com/embed/LVrTSe0JSLM 114 2026-10-05T20:52:01+00:00 yes https://xdme.com/watch-book23-q051.html https://xdme.com/book23-thumbs/page-051.jpg How Does a Jet Engine Work? A jet engine follows four simple steps. Suck, squeeze, bang, blow! Let's go through them one by one. Parts of a jet engine run hotter than the melting point of their metal, so cool https://socialmedia.xdme.com/tony/videos-book23/page-051.mp4 https://www.youtube.com/embed/IRExo2kHACE 105 2026-10-05T20:54:33+00:00 yes https://xdme.com/watch-book23-q052.html https://xdme.com/book23-thumbs/page-052.jpg What Does the Huge Fan at the Front of a Jet Engine Do? The front of a jet engine has a huge fan. It looks like a giant propeller in a tube. What does it do? The fan on the biggest engines is wider than a small airplane's body. https://socialmedia.xdme.com/tony/videos-book23/page-052.mp4 https://www.youtube.com/embed/v-dQJ1WqmSE 104 2026-10-05T20:57:04+00:00 yes https://xdme.com/watch-book23-q053.html https://xdme.com/book23-thumbs/page-053.jpg What Do All the Dials in a Cockpit Tell the Pilots? A cockpit is full of dials and screens. Each one gives pilots important information. Modern cockpits have big screens that combine many dials in one. https://socialmedia.xdme.com/tony/videos-book23/page-053.mp4 https://www.youtube.com/embed/gTbxxC2KDgQ 113 2026-10-05T21:00:06+00:00 yes https://xdme.com/watch-book23-q054.html https://xdme.com/book23-thumbs/page-054.jpg How Does an Altimeter Know How High a Plane Is? How does an airplane know how high it is? It feels the air! The tool is called an altimeter. Air pressure drops by about half at eighteen thousand feet. https://socialmedia.xdme.com/tony/videos-book23/page-054.mp4 https://www.youtube.com/embed/pJ5icEU6bCA 110 2026-10-05T21:02:37+00:00 yes https://xdme.com/watch-book23-q055.html https://xdme.com/book23-thumbs/page-055.jpg How Does a Plane Know How Fast the Air Is Flowing Past It? How does a plane know how fast air is flowing past it? It uses a thin tube sticking out the front. It is called a pitot tube! Pitot tubes are named for Henri Pitot, a French scient https://socialmedia.xdme.com/tony/videos-book23/page-055.mp4 https://www.youtube.com/embed/hb7GGNYZaTE 107 2026-10-05T21:05:09+00:00 yes https://xdme.com/watch-book23-q056.html https://xdme.com/book23-thumbs/page-056.jpg What Is an Artificial Horizon, and Why Do Pilots Need It? In clouds or at night, a pilot cannot see the real horizon. It is easy to lose track of which way is up. An instrument helps! A spinning gyroscope tends to keep pointing the same w https://socialmedia.xdme.com/tony/videos-book23/page-056.mp4 https://www.youtube.com/embed/SnoqSGf8oLI 112 2026-10-05T21:08:10+00:00 yes https://xdme.com/watch-book23-q057.html https://xdme.com/book23-thumbs/page-057.jpg What Does an Autopilot Do? An autopilot is a computer that can fly a plane along a set path. It does not replace the pilots. It is more like a helper! Autopilots were first used in the nineteen tens. https://socialmedia.xdme.com/tony/videos-book23/page-057.mp4 https://www.youtube.com/embed/k-gqhfD0O8Y 108 2026-10-05T21:10:41+00:00 yes https://xdme.com/watch-book23-q058.html https://xdme.com/book23-thumbs/page-058.jpg Why Do Planes Fold Their Wheels Up After Takeoff? After take-off, planes fold their wheels up. They disappear into the body of the plane. There is a smart reason! Some small planes keep their wheels down all the time. https://socialmedia.xdme.com/tony/videos-book23/page-058.mp4 https://www.youtube.com/embed/oIv6j13WD_s 107 2026-10-05T21:13:12+00:00 yes https://xdme.com/watch-book23-q059.html https://xdme.com/book23-thumbs/page-059.jpg Why Is the "Black Box" on an Airplane Actually Orange? Airplanes have a special recorder called a black box. Strangely, it is not black at all. It is bright orange! Flight recorders are placed in the tail, where they are best protected https://socialmedia.xdme.com/tony/videos-book23/page-059.mp4 https://www.youtube.com/embed/_OwH4s-Dmpg 108 2026-10-05T21:15:44+00:00 yes https://xdme.com/watch-book23-q060.html https://xdme.com/book23-thumbs/page-060.jpg What Makes the White Trails That Jets Leave Behind? Jets sometimes leave long white trails in the sky. They look like clouds made by a plane. And that is almost what they are! Long-lasting contrails can turn into wispy clouds. https://socialmedia.xdme.com/tony/videos-book23/page-060.mp4 https://www.youtube.com/embed/S6IeYiYPQ2U 110 2026-10-05T21:18:15+00:00 yes https://xdme.com/watch-book23-q061.html https://xdme.com/book23-thumbs/page-061.jpg Why Do Airplane Windows Have Round Corners and a Tiny Hole? Airplane windows have round corners. They also have a tiny hole. Both are clever safety ideas! Airplane windows have several layers of plastic for strength. https://socialmedia.xdme.com/tony/videos-book23/page-061.mp4 https://www.youtube.com/embed/RqHRn45Q_xM 113 2026-10-05T21:21:17+00:00 yes https://xdme.com/watch-book23-q062.html https://xdme.com/book23-thumbs/page-062.jpg How Does a Plane Keep the Air Comfortable at 35,000 Feet? Outside a jet at 35,000 feet, the air is thin and freezing. Inside, passengers breathe easily. How does the plane do that? The cabin air is replaced many times every hour. https://socialmedia.xdme.com/tony/videos-book23/page-062.mp4 https://www.youtube.com/embed/AQUk0Steptw 109 2026-10-05T21:23:48+00:00 yes https://xdme.com/watch-book23-q063.html https://xdme.com/book23-thumbs/page-063.jpg What Is Turbulence, and Why Does It Happen? Sometimes a plane shakes in the sky. The seat belt light goes on. That bumpiness is called turbulence! The jet stream can cause bumpy air at high altitude, even in clear skies. https://socialmedia.xdme.com/tony/videos-book23/page-063.mp4 https://www.youtube.com/embed/rQvwphsLFUc 107 2026-10-05T21:26:19+00:00 yes https://xdme.com/watch-book23-q064.html https://xdme.com/book23-thumbs/page-064.jpg Why Do Flight Attendants Ask for Tray Tables and Seats to Be Upright? Flight attendants ask everyone to put tray tables away and seats upright. It happens at takeoff and landing. There is a good reason! https://socialmedia.xdme.com/tony/videos-book23/page-064.mp4 https://www.youtube.com/embed/suqSXMQ5O4M 115 2026-10-05T21:29:21+00:00 yes https://xdme.com/watch-book23-q065.html https://xdme.com/book23-thumbs/page-065.jpg Why Are Most Airplanes Painted White? Look at most airplanes. They are white! Why not bright colors? Some airplane paints are made to resist ultraviolet light and very low temperatures. https://socialmedia.xdme.com/tony/videos-book23/page-065.mp4 https://www.youtube.com/embed/C8YYXehYp7c 112 2026-10-05T21:31:52+00:00 yes https://xdme.com/watch-book23-q066.html https://xdme.com/book23-thumbs/page-066.jpg What Are the Panels That Pop Up on the Wings After Landing? After landing, panels pop up on the wings. They look like little flaps standing up. What are they doing? Spoilers can be raised on just one wing to help a plane roll. https://socialmedia.xdme.com/tony/videos-book23/page-066.mp4 https://www.youtube.com/embed/_N7u1x6ZpQM 107 2026-10-05T21:34:24+00:00 yes https://xdme.com/watch-book23-q067.html https://xdme.com/book23-thumbs/page-067.jpg How Do Airplanes Slow Down So Fast After They Land? A landing plane rushes down the runway. Then it slows down quickly. It uses several tools at once! A big jet can stop from 150 miles per hour in about a mile of runway. https://socialmedia.xdme.com/tony/videos-book23/page-067.mp4 https://www.youtube.com/embed/WcDdaES0DEY 111 2026-10-05T21:37:38+00:00 yes https://xdme.com/watch-book23-q068.html https://xdme.com/book23-thumbs/page-068.jpg What Is an Airplane Made Of? An airplane must be strong, but also light. What do engineers use? Almost half of a Boeing 787 is made of composite materials. Composites are made of layers of fibers. https://socialmedia.xdme.com/tony/videos-book23/page-068.mp4 https://www.youtube.com/embed/ZM_Kg30qL7k 115 2026-10-05T21:40:09+00:00 yes https://xdme.com/watch-book23-q069.html https://xdme.com/book23-thumbs/page-069.jpg How Many Parts Does a Jumbo Jet Have? A jumbo jet is a giant puzzle. How many pieces does it have? The number may surprise you! A jumbo jet has hundreds of miles of wiring inside it. https://socialmedia.xdme.com/tony/videos-book23/page-069.mp4 https://www.youtube.com/embed/GmNQUatSnvM 109 2026-10-05T21:42:46+00:00 yes https://xdme.com/watch-book23-q070.html https://xdme.com/book23-thumbs/page-070.jpg How Do Planes Get Cleared of Ice in Winter? In winter, ice can form on a plane's wings. That is dangerous. So crews have a way to remove it! De-icing fluid is often orange or green so crews can see where it has been sprayed. https://socialmedia.xdme.com/tony/videos-book23/page-070.mp4 https://www.youtube.com/embed/0KsZdXaseTE 110 2026-10-05T21:45:17+00:00 yes https://xdme.com/watch-book23-q071.html https://xdme.com/book23-thumbs/page-071.jpg What Happens When Lightning Strikes an Airplane? Lightning can strike an airplane. That sounds scary! But planes are built for it. Planes have little wicks on their wings to let static electricity slip away. https://socialmedia.xdme.com/tony/videos-book23/page-071.mp4 https://www.youtube.com/embed/sfJgdT5hoiw 111 2026-10-05T21:47:48+00:00 yes https://xdme.com/watch-book23-q072.html https://xdme.com/book23-thumbs/page-072.jpg Where Does an Airplane Carry Its Fuel? A big jet burns lots of fuel. Where does it keep it all? Mostly in the wings! Jet fuel is a type of kerosene. Big jets hold tens of thousands of gallons. https://socialmedia.xdme.com/tony/videos-book23/page-072.mp4 https://www.youtube.com/embed/HErFYW326v0 108 2026-10-05T21:50:20+00:00 yes https://xdme.com/watch-book23-q073.html https://xdme.com/book23-thumbs/page-073.jpg Where Do Suitcases and Cargo Ride on an Airplane? Where do suitcases go on a plane? They ride below your feet! Large cargo planes can carry heavy things like helicopters. Each bag has a tag for its trip. https://socialmedia.xdme.com/tony/videos-book23/page-073.mp4 https://www.youtube.com/embed/r5z3-NRW91g 110 2026-10-05T21:52:51+00:00 yes https://xdme.com/watch-book23-q074.html https://xdme.com/book23-thumbs/page-074.jpg How Can a Plane Land Safely in Thick Fog? Fog can hide the runway completely. Can a plane still land? Yes, with special instruments! Pilots have special rules about how low they can go without seeing the runway. https://socialmedia.xdme.com/tony/videos-book23/page-074.mp4 https://www.youtube.com/embed/h-_3DcrNtKg 111 2026-10-05T21:55:53+00:00 yes https://xdme.com/watch-book23-q075.html https://xdme.com/book23-thumbs/page-075.jpg How Can a Floatplane Take Off From a Lake? Some airplanes take off from a lake. They do not have wheels! They have floats. Floatplanes can reach remote spots with no roads. Some floatplanes have wheels and floats. https://socialmedia.xdme.com/tony/videos-book23/page-075.mp4 https://www.youtube.com/embed/_YZQxMKmJNE 106 2026-10-05T21:58:25+00:00 yes https://xdme.com/watch-book23-q076.html https://xdme.com/book23-thumbs/page-076.jpg What Makes a Helium Balloon Float Up While a Regular Balloon Sinks? A helium balloon floats up. A balloon you blow up yourself sinks. What is the difference? Helium is the second lightest element in the universe, after hydrogen. https://socialmedia.xdme.com/tony/videos-book23/page-076.mp4 https://www.youtube.com/embed/3z1R2GQzp5c 112 2026-10-05T19:11:57+00:00 yes https://xdme.com/watch-book23-q077.html https://xdme.com/book23-thumbs/page-077.jpg Why Does Helium Change the Sound of a Voice? Helium makes the voice squeaky. It sounds funny! But why does it change? Sound goes slower in heavy gases, which can make voices deeper. https://socialmedia.xdme.com/tony/videos-book23/page-077.mp4 https://www.youtube.com/embed/QwOgS2bf3hs 108 2026-10-05T19:11:58+00:00 yes https://xdme.com/watch-book23-q078.html https://xdme.com/book23-thumbs/page-078.jpg What Do the Burner and the Top Vent Do During a Balloon Ride? A hot air balloon has a burner and a vent. One makes it go up. One brings it down. A hot air balloon's top can be hotter than boiling water. https://socialmedia.xdme.com/tony/videos-book23/page-078.mp4 https://www.youtube.com/embed/2Pae1Vh8BC0 103 2026-10-05T19:12:01+00:00 yes https://xdme.com/watch-book23-q079.html https://xdme.com/book23-thumbs/page-079.jpg How Can a Balloonist Pick a Direction Without a Steering Wheel? A balloon has no steering wheel. How does the pilot choose where to go? By finding the right wind! Balloon races are won by pilots who find the best winds. https://socialmedia.xdme.com/tony/videos-book23/page-079.mp4 https://www.youtube.com/embed/y4h-JCjuhDY 104 2026-10-05T19:12:02+00:00 yes https://xdme.com/watch-book23-q080.html https://xdme.com/book23-thumbs/page-080.jpg When Did People First Fly in a Balloon? Long ago, people only dreamed of flying. Then some clever brothers built a balloon. And people finally flew! Their balloon was decorated with bright paintings. https://socialmedia.xdme.com/tony/videos-book23/page-080.mp4 https://www.youtube.com/embed/AXtwVMET0h0 115 2026-10-05T19:12:03+00:00 yes https://xdme.com/watch-book23-q081.html https://xdme.com/book23-thumbs/page-081.jpg What Makes a Blimp Different From a Drifting Balloon? A balloon drifts with the wind. A blimp can go where the pilot wants. What is the difference? A big blimp can stay aloft for many hours. https://socialmedia.xdme.com/tony/videos-book23/page-081.mp4 https://www.youtube.com/embed/s-hIsVOpUSM 110 2026-10-05T19:12:05+00:00 yes https://xdme.com/watch-book23-q082.html https://xdme.com/book23-thumbs/page-082.jpg Why Do Airships Use Helium Instead of Hydrogen? Hydrogen is lighter than helium. So why do airships use helium? Safety! Hydrogen is also the fuel of the Sun. Hydrogen can catch fire easily. https://socialmedia.xdme.com/tony/videos-book23/page-082.mp4 https://www.youtube.com/embed/QzxHLtDuiEo 111 2026-10-05T19:12:06+00:00 yes https://xdme.com/watch-book23-q083.html https://xdme.com/book23-thumbs/page-083.jpg Why Does a Weather Balloon Swell as It Rises, and Then Pop? A weather balloon starts small. As it rises, it swells. Then it pops! Weather balloons are launched twice a day from sites all over the world. https://socialmedia.xdme.com/tony/videos-book23/page-083.mp4 https://www.youtube.com/embed/vHiel4Aal-Y 108 2026-10-05T19:12:07+00:00 yes https://xdme.com/watch-book23-q084.html https://xdme.com/book23-thumbs/page-084.jpg How Do the Spinning Blades of a Helicopter Make Lift? A helicopter has spinning blades. They do not push it like a fan. They are tiny wings! Helicopter blades are called rotors. They often bend slightly in flight. https://socialmedia.xdme.com/tony/videos-book23/page-084.mp4 https://www.youtube.com/embed/PRTHuMA_qDo 109 2026-10-05T19:12:08+00:00 yes https://xdme.com/watch-book23-q085.html https://xdme.com/book23-thumbs/page-085.jpg Why Does a Helicopter Have a Little Propeller on Its Tail? Look at the tail of a helicopter. There is a little propeller! What is it for? The Chinook helicopter has two big rotors, one at the front and one at the back. https://socialmedia.xdme.com/tony/videos-book23/page-085.mp4 https://www.youtube.com/embed/Y6gt8JkuY8E 112 2026-10-05T19:12:10+00:00 yes https://xdme.com/watch-book23-q086.html https://xdme.com/book23-thumbs/page-086.jpg How Does a Helicopter Lean to Fly Forward? A helicopter leans to go forward. The pilot tilts the whole spinning rotor. A special control does it. The cyclic control is like a joystick between the pilot's knees. https://socialmedia.xdme.com/tony/videos-book23/page-086.mp4 https://www.youtube.com/embed/oZao__M421Y 109 2026-10-05T19:12:12+00:00 yes https://xdme.com/watch-book23-q087.html https://xdme.com/book23-thumbs/page-087.jpg Why Can a Helicopter Fly Sideways and Backward? A plane cannot fly backward. But a helicopter can! How is that possible? Some helicopters can even turn in place while hovering. Hovering means staying in one spot. https://socialmedia.xdme.com/tony/videos-book23/page-087.mp4 https://www.youtube.com/embed/9cKKWPoKOno 114 2026-10-05T19:12:13+00:00 yes https://xdme.com/watch-book23-q088.html https://xdme.com/book23-thumbs/page-088.jpg What Happens If a Helicopter's Engine Stops? What if a helicopter's engine stops? Pilots train for this. There is a clever safety trick! Helicopter pilots practice autorotation landings with an instructor as part of their tra https://socialmedia.xdme.com/tony/videos-book23/page-088.mp4 https://www.youtube.com/embed/qG9thaf5lp8 113 2026-10-05T19:12:22+00:00 yes https://xdme.com/watch-book23-q089.html https://xdme.com/book23-thumbs/page-089.jpg What Jobs Do Helicopters Do? Helicopters can land almost anywhere. That makes them great helpers. What jobs do they do? Some rescue helicopters can lift a person from a boat using a winch. https://socialmedia.xdme.com/tony/videos-book23/page-089.mp4 https://www.youtube.com/embed/OZWUxM7yXNI 113 2026-10-05T19:12:33+00:00 yes https://xdme.com/watch-book23-q090.html https://xdme.com/book23-thumbs/page-090.jpg How Do Paragliders Stay Up in the Air? A paraglider has no engine. Just a soft wing and the air. How does it stay up? Paragliders can climb thousands of feet in strong thermals. https://socialmedia.xdme.com/tony/videos-book23/page-090.mp4 https://www.youtube.com/embed/SiBz_ZF5ssk 115 2026-10-05T19:12:35+00:00 yes https://xdme.com/watch-book23-q091.html https://xdme.com/book23-thumbs/page-091.jpg How Can a Sailplane Glide for Hundreds of Miles? A sailplane has no engine. Yet it can fly hundreds of miles! How does it keep going? Some sailplanes can travel fifty feet forward for every foot they drop. https://socialmedia.xdme.com/tony/videos-book23/page-091.mp4 https://www.youtube.com/embed/w4jVN3pJMVo 109 2026-10-05T19:14:08+00:00 yes https://xdme.com/watch-book23-q092.html https://xdme.com/book23-thumbs/page-092.jpg What Is a Glide Ratio? How far can a plane glide? There is a number that tells you. It is called the glide ratio. A jet at cruising height could glide more than a hundred miles if its engines stopped. https://socialmedia.xdme.com/tony/videos-book23/page-092.mp4 https://www.youtube.com/embed/b6VyZDpbH9M 111 2026-10-05T19:17:23+00:00 yes https://xdme.com/watch-book23-q093.html https://xdme.com/book23-thumbs/page-093.jpg How Does a Boomerang Come Back? Throw a boomerang and it comes back! That seems like magic. But it is physics. Boomerangs come in many shapes, and not all of them come back. https://socialmedia.xdme.com/tony/videos-book23/page-093.mp4 https://www.youtube.com/embed/xOQCPBfAtF4 109 2026-10-05T19:19:55+00:00 yes https://xdme.com/watch-book23-q094.html https://xdme.com/book23-thumbs/page-094.jpg What Is the Difference Between Lighter-Than-Air and Heavier-Than-Air Flight? Some things fly because they are lighter than air. Others are heavier but still fly. Two big ideas in flight! Some modern designs mix both ideas in a hybrid airship. https://socialmedia.xdme.com/tony/videos-book23/page-094.mp4 https://www.youtube.com/embed/eJwx0l7vmrg 113 2026-10-05T19:23:32+00:00 yes https://xdme.com/watch-book23-q095.html https://xdme.com/book23-thumbs/page-095.jpg What Are Electric Air Taxis? Imagine a quiet flying taxi over a city. Some are being tested right now. They are electric air taxis! Air taxis are sometimes called eVTOLs. https://socialmedia.xdme.com/tony/videos-book23/page-095.mp4 https://www.youtube.com/embed/7UiS1bJiBpI 110 2026-10-05T19:26:35+00:00 yes https://xdme.com/watch-book23-q096.html https://xdme.com/book23-thumbs/page-096.jpg Can a Plane Fly Using Only Sunshine? Can a plane fly with no fuel? Yes! A solar plane flew around the world. One pilot flew at a time and sometimes stayed up for several days. https://socialmedia.xdme.com/tony/videos-book23/page-096.mp4 https://www.youtube.com/embed/XGokCOAITng 107 2026-10-05T19:29:13+00:00 yes https://xdme.com/watch-book23-q097.html https://xdme.com/book23-thumbs/page-097.jpg How Do Stunt Pilots Do Loops and Rolls? At airshows, planes loop and roll. Those are stunt planes. How do the pilots do it? Stunt pilots feel forces several times their own weight in tight turns. https://socialmedia.xdme.com/tony/videos-book23/page-097.mp4 https://www.youtube.com/embed/GI-Tc0O4lwQ 108 2026-10-05T19:31:45+00:00 yes https://xdme.com/watch-book23-q098.html https://xdme.com/book23-thumbs/page-098.jpg How Do Firefighting Planes Scoop Up Water From a Lake? Some planes fight forest fires. They scoop up water without landing. Wow! Water bombers are made in Canada. They use two small scoops. https://socialmedia.xdme.com/tony/videos-book23/page-098.mp4 https://www.youtube.com/embed/bLp6X4MdjtE 109 2026-10-05T19:34:49+00:00 yes https://xdme.com/watch-book23-q099.html https://xdme.com/book23-thumbs/page-099.jpg Can a Plane Fly on Human Leg Power? Could you fly by pedaling? Someone really did it! Across the English Channel. Its wings stretched about ninety-six feet. That is longer than two school buses parked end to end. https://socialmedia.xdme.com/tony/videos-book23/page-099.mp4 https://www.youtube.com/embed/jqFuVYrhk3Q 110 2026-10-05T19:37:52+00:00 yes https://xdme.com/watch-book23-q100.html https://xdme.com/book23-thumbs/page-100.jpg How Do Bush Planes Land on Short, Bumpy Strips? Some places have no airports. Bush planes can land on gravel, snow, or water. How do they manage? This kind of flying is called STOL, short for short takeoff and landing. https://socialmedia.xdme.com/tony/videos-book23/page-100.mp4 https://www.youtube.com/embed/5VYihESpYL0 111 2026-10-05T19:41:28+00:00 yes https://xdme.com/watch-book23-q101.html https://xdme.com/book23-thumbs/page-101.jpg How Do People Learn to Become Pilots? Every pilot started as a beginner. They learned step by step. Here is how. Many places let people take their first flying lessons as teenagers. https://socialmedia.xdme.com/tony/videos-book23/page-101.mp4 https://www.youtube.com/embed/dSzMNUGySYM 113 2026-10-05T19:43:59+00:00 yes https://xdme.com/watch-book23-q102.html https://xdme.com/book23-thumbs/page-102.jpg What Is a Flight Simulator? Pilots practice in a machine that never leaves the ground. It feels like flying! It is called a flight simulator. Astronauts also train in simulators. https://socialmedia.xdme.com/tony/videos-book23/page-102.mp4 https://www.youtube.com/embed/bSXHHdWgWfI 110 2026-10-05T19:47:03+00:00 yes https://xdme.com/watch-book23-q103.html https://xdme.com/book23-thumbs/page-103.jpg What Do Pilots Check Before They Take Off? Pilots do not just jump in and go. They check lots of things first. Surgeons, astronauts, and mountain climbers use checklists too. https://socialmedia.xdme.com/tony/videos-book23/page-103.mp4 https://www.youtube.com/embed/IuWJI_jZKOA 102 2026-10-05T19:50:07+00:00 yes https://xdme.com/watch-book23-q104.html https://xdme.com/book23-thumbs/page-104.jpg Why Do Airports Scan Bags with X-Rays? At the airport, your bag rides through a scanner. It sees inside without opening it! How? Doctors use X-rays to take pictures of bones. https://socialmedia.xdme.com/tony/videos-book23/page-104.mp4 https://www.youtube.com/embed/gytDjS0sg-s 109 2026-10-05T19:53:18+00:00 yes https://xdme.com/watch-book23-q105.html https://xdme.com/book23-thumbs/page-105.jpg Why Do Pilots Say "Alpha, Bravo, Charlie" When They Talk on the Radio? Pilots say funny words like Alpha, Bravo, and Charlie. They are not just being silly. It keeps flights safe. Many jobs use this alphabet, including ships and police. https://socialmedia.xdme.com/tony/videos-book23/page-105.mp4 https://www.youtube.com/embed/Aj09xaJULdU 117 2026-10-05T19:56:21+00:00 yes https://xdme.com/watch-book23-q106.html https://xdme.com/book23-thumbs/page-106.jpg What Does an Air Traffic Controller Do? The sky is busy with planes. Someone has to keep them apart. Meet the air traffic controller! Controllers often handle many planes at the same time. https://socialmedia.xdme.com/tony/videos-book23/page-106.mp4 https://www.youtube.com/embed/XUbRg4ESlFk 108 2026-10-05T19:59:24+00:00 yes https://xdme.com/watch-book23-q107.html https://xdme.com/book23-thumbs/page-107.jpg Why Does an Airport Have a Tall Control Tower? Every big airport has a tall tower. It has big windows at the top. Why so high? Some small airports have towers only during certain hours. https://socialmedia.xdme.com/tony/videos-book23/page-107.mp4 https://www.youtube.com/embed/1hFGgTZfqtU 110 2026-10-05T20:02:27+00:00 yes https://xdme.com/watch-book23-q108.html https://xdme.com/book23-thumbs/page-108.jpg How Do Planes Stay Safely Apart in a Crowded Sky? Thousands of planes fly each day. How do they never bump? Layers of safety! Planes going east and west usually fly at different heights. https://socialmedia.xdme.com/tony/videos-book23/page-108.mp4 https://www.youtube.com/embed/5_ofCdfna-U 113 2026-10-05T20:05:30+00:00 yes https://xdme.com/watch-book23-q109.html https://xdme.com/book23-thumbs/page-109.jpg How Does Radar See Airplanes? Radar can see a plane far away. It does not use eyes. It listens for echoes! Radio waves travel at the speed of light. An echo is a sound that bounces back. https://socialmedia.xdme.com/tony/videos-book23/page-109.mp4 https://www.youtube.com/embed/OQdU1WgyElM 110 2026-10-05T20:08:47+00:00 yes https://xdme.com/watch-book23-q110.html https://xdme.com/book23-thumbs/page-110.jpg How Do Pilots Find Their Way Across an Ocean? Over an ocean there are no signs. Pilots cannot see any roads. So how do they find their way? Some planes also use a spinning gyroscope system to know how they have moved. https://socialmedia.xdme.com/tony/videos-book23/page-110.mp4 https://www.youtube.com/embed/xH10VwEgGTs 114 2026-10-05T20:11:19+00:00 yes https://xdme.com/watch-book23-q111.html https://xdme.com/book23-thumbs/page-111.jpg Why Do Flight Paths Look Curved on a Flat Map? Earth is round like a ball. The shortest path is a great circle. On a flat map that path looks bent! Earth is a round globe, not a flat sheet. https://socialmedia.xdme.com/tony/videos-book23/page-111.mp4 https://www.youtube.com/embed/8LJKJN4kBIg 118 2026-10-05T22:35:37+00:00 yes https://xdme.com/watch-book23-q112.html https://xdme.com/book23-thumbs/page-112.jpg Why Do Runways Have Numbers? Every runway has a number. That number is a direction clue. It tells pilots which way the runway points! Runway numbers come from compass degrees. https://socialmedia.xdme.com/tony/videos-book23/page-112.mp4 https://www.youtube.com/embed/-6C4Kb085ko 127 2026-10-05T22:38:38+00:00 yes https://xdme.com/watch-book23-q113.html https://xdme.com/book23-thumbs/page-113.jpg What Do the Lines and Lights on a Runway Mean? Runways have lines and lights. They work like road signs for pilots. Colors and shapes tell them where to go! White stripes mark the ends of a runway. https://socialmedia.xdme.com/tony/videos-book23/page-113.mp4 https://www.youtube.com/embed/3JpmRQok7Uw 119 2026-10-05T22:41:09+00:00 yes https://xdme.com/watch-book23-q114.html https://xdme.com/book23-thumbs/page-114.jpg Why Do Airports Have So Many Different Kinds of Vehicles? Airports are busy places. Many special vehicles help each plane. Every truck has one important job! Fuel trucks fill the tanks. Baggage carts and belt loaders move suitcases. https://socialmedia.xdme.com/tony/videos-book23/page-114.mp4 https://www.youtube.com/embed/utH8Mf2TKzA 121 2026-10-05T22:44:10+00:00 yes https://xdme.com/watch-book23-q115.html https://xdme.com/book23-thumbs/page-115.jpg Why Does a Tug Push an Airplane Away From the Gate? A jet at the gate faces the building. It cannot safely back up alone. A strong tug pushes it out! At the gate, a jet usually faces the building. https://socialmedia.xdme.com/tony/videos-book23/page-115.mp4 https://www.youtube.com/embed/V5cbRVYd4HQ 118 2026-10-05T22:46:42+00:00 yes https://xdme.com/watch-book23-q116.html https://xdme.com/book23-thumbs/page-116.jpg How Long Does It Take to Get a Plane Ready Between Flights? Planes do not rest for long. A turnaround can take under an hour. Teamwork makes it happen fast! A quick turnaround can take as little as 30 to 60 minutes. https://socialmedia.xdme.com/tony/videos-book23/page-116.mp4 https://www.youtube.com/embed/Wy9c-kkQiEo 122 2026-10-05T22:49:43+00:00 yes https://xdme.com/watch-book23-q117.html https://xdme.com/book23-thumbs/page-117.jpg Why Does a Flight From Toronto to London Take Less Time than the Trip Back? Winds high above Earth are super fast. Going east can feel like a push. Coming west pushes against you! The jet stream usually blows from west to east. https://socialmedia.xdme.com/tony/videos-book23/page-117.mp4 https://www.youtube.com/embed/qU3TJo0R2Yw 121 2026-10-05T22:52:14+00:00 yes https://xdme.com/watch-book23-q118.html https://xdme.com/book23-thumbs/page-118.jpg What Is Jet Lag? Your body has a clock inside. Flying far can confuse that clock. That mixed-up feeling is jet lag! Your body has an internal clock for sleep and wake. https://socialmedia.xdme.com/tony/videos-book23/page-118.mp4 https://www.youtube.com/embed/MSB3pEhPCCM 121 2026-10-05T22:55:23+00:00 yes https://xdme.com/watch-book23-q119.html https://xdme.com/book23-thumbs/page-119.jpg How Far Can You See From a Plane Window? A plane window view feels huge. The ground shrinks into tiny shapes. On a clear day you can see for miles! From 35,000 feet, you can see over 200 miles to the horizon on a clear da https://socialmedia.xdme.com/tony/videos-book23/page-119.mp4 https://www.youtube.com/embed/V_uTz7ce8fc 123 2026-10-05T22:57:54+00:00 yes https://xdme.com/watch-book23-q120.html https://xdme.com/book23-thumbs/page-120.jpg How Many Planes Are in the Sky at Once? The sky looks empty from the ground. But many planes share the air at once. Trackers turn them into moving dots! At a busy moment, thousands of airliners are flying around the worl https://socialmedia.xdme.com/tony/videos-book23/page-120.mp4 https://www.youtube.com/embed/u-Vr4hbo_1o 122 2026-10-05T23:00:56+00:00 yes https://xdme.com/watch-book23-q121.html https://xdme.com/book23-thumbs/page-121.jpg How Do Airports Keep Birds Away From Runways? Birds and planes should not share a runway. Airports use many gentle ways to keep birds away. That protects birds and passengers! Short grass makes birds move on. https://socialmedia.xdme.com/tony/videos-book23/page-121.mp4 https://www.youtube.com/embed/U6fqRm99w6U 120 2026-10-05T23:03:27+00:00 yes https://xdme.com/watch-book23-q122.html https://xdme.com/book23-thumbs/page-122.jpg Why Does a Puff of Smoke Appear When a Plane Lands? When a plane lands, you may see a puff of smoke. The wheels were not spinning yet. Friction makes a tiny bit of rubber wear off! The smoke is tiny bits of rubber. https://socialmedia.xdme.com/tony/videos-book23/page-122.mp4 https://www.youtube.com/embed/Znryv6kmDas 116 2026-10-05T23:06:30+00:00 yes https://xdme.com/watch-book23-q123.html https://xdme.com/book23-thumbs/page-123.jpg What Are Some of the Biggest Airplanes Ever Built? Some airplanes are truly huge. One carries hundreds of people on two decks. Another has wings longer than a football field! The A380 can carry hundreds of people. https://socialmedia.xdme.com/tony/videos-book23/page-123.mp4 https://www.youtube.com/embed/Gdn8nkLZQFA 131 2026-10-05T23:09:31+00:00 yes https://xdme.com/watch-book23-q124.html https://xdme.com/book23-thumbs/page-124.jpg How Did Concorde Cross the Atlantic in About Three Hours? Concorde crossed the Atlantic in about three hours. It flew faster than the speed of sound. That is about twice as fast as ordinary jets! https://socialmedia.xdme.com/tony/videos-book23/page-124.mp4 https://www.youtube.com/embed/N2hMiYQlGsY 124 2026-10-05T23:12:02+00:00 yes https://xdme.com/watch-book23-q125.html https://xdme.com/book23-thumbs/page-125.jpg How Are New Airplanes Tested Before They Carry People? New airplanes face years of tough tests. Engineers push them harder than real flights will. Only then may they carry people! Testing can take years. https://socialmedia.xdme.com/tony/videos-book23/page-125.mp4 https://www.youtube.com/embed/8WjUMT0PTc8 121 2026-10-05T23:15:03+00:00 yes https://xdme.com/watch-book23-q126.html https://xdme.com/book23-thumbs/page-126.jpg Which Paper Plane Designs Fly the Farthest, and Why? Paper planes come in two main styles. Darts are fast and pointed. Gliders float on wide wings! Darts fly fast and straight. Gliders float slowly and gently. https://socialmedia.xdme.com/tony/videos-book23/page-126.mp4 https://www.youtube.com/embed/Sd5F6ZQq21g 119 2026-10-05T23:17:35+00:00 yes https://xdme.com/watch-book23-q127.html https://xdme.com/book23-thumbs/page-127.jpg How Do You Test a Paper Plane Fairly? A fair test changes only one thing. Everything else stays the same. Many tries beat one lucky throw! One-change tests are called controlled experiments. https://socialmedia.xdme.com/tony/videos-book23/page-127.mp4 https://www.youtube.com/embed/VWRlcTp6pa4 121 2026-10-05T23:20:48+00:00 yes https://xdme.com/watch-book23-q128.html https://xdme.com/book23-thumbs/page-128.jpg What Happens When You Put a Paper Clip on the Tail of a Plane? Balance decides how a paper plane glides. A clip on the nose can steady it. A clip on the tail can make it wobble! A nose clip moves balance forward. https://socialmedia.xdme.com/tony/videos-book23/page-128.mp4 https://www.youtube.com/embed/U9CJt_QDp1A 121 2026-10-05T23:23:19+00:00 yes https://xdme.com/watch-book23-q129.html https://xdme.com/book23-thumbs/page-129.jpg Why Do Paper Planes Fly Steadier When Their Wings Tilt Up Into a Shallow V? Wings tilted up in a shallow V help a plane stay steady. If it rolls, the low wing gets more lift. That swing rights the plane! Dihedral means wings tilt up like a shallow V. https://socialmedia.xdme.com/tony/videos-book23/page-129.mp4 https://www.youtube.com/embed/xshnrkygatI 125 2026-10-05T23:26:20+00:00 yes https://xdme.com/watch-book23-q130.html https://xdme.com/book23-thumbs/page-130.jpg How Can Small Bends in the Back of the Wings Stop a Plane From Diving? Tiny bends at the back of the wings can fix a dive. They work like elevators on a real airplane. Pilots call this trimming! Bend up to raise the nose. https://socialmedia.xdme.com/tony/videos-book23/page-130.mp4 https://www.youtube.com/embed/CAw1qYrvaVE 122 2026-10-05T23:28:52+00:00 yes https://xdme.com/watch-book23-q131.html https://xdme.com/book23-thumbs/page-131.jpg Why Does a Paper Helicopter Spin as It Falls? A paper helicopter falls and spins. Its flaps face opposite ways. So why does that make it twirl? A real maple seed spins down in the same way. https://socialmedia.xdme.com/tony/videos-book23/page-131.mp4 https://www.youtube.com/embed/5LP_7K3BiMk 117 2026-10-05T23:32:00+00:00 yes https://xdme.com/watch-book23-q132.html https://xdme.com/book23-thumbs/page-132.jpg Do Bigger Wings Always Fly Better? Bigger wings make more lift. But they also add weight and drag. So do bigger wings always win? Airliner wings are long and thin for long glides. https://socialmedia.xdme.com/tony/videos-book23/page-132.mp4 https://www.youtube.com/embed/B0TdzjZtYxw 112 2026-10-05T23:34:02+00:00 yes https://xdme.com/watch-book23-q133.html https://xdme.com/book23-thumbs/page-133.jpg What Do the Tail and String of a Kite Do? A kite has a tail and a string. They look simple, but they matter. What jobs do they do? A longer tail adds more drag and steadiness. https://socialmedia.xdme.com/tony/videos-book23/page-133.mp4 https://www.youtube.com/embed/doBx8kBvLdE 110 2026-10-05T23:37:03+00:00 yes https://xdme.com/watch-book23-q134.html https://xdme.com/book23-thumbs/page-134.jpg Where Is It Safe to Fly a Kite? Kites need lots of open sky. Some places are dangerous. So where is it safe to fly? Stay far from power lines, because a kite string can carry electricity. https://socialmedia.xdme.com/tony/videos-book23/page-134.mp4 https://www.youtube.com/embed/lx_55AHIeS4 113 2026-10-05T23:39:34+00:00 yes https://xdme.com/watch-book23-q135.html https://xdme.com/book23-thumbs/page-135.jpg What Makes a Diamond Kite Fly Well? A diamond kite looks simple. Two sticks and light cover. So what makes it fly so well? People have flown diamond kites for thousands of years in places like China. https://socialmedia.xdme.com/tony/videos-book23/page-135.mp4 https://www.youtube.com/embed/BoIqjEoInMg 114 2026-10-05T23:42:36+00:00 yes https://xdme.com/watch-book23-q136.html https://xdme.com/book23-thumbs/page-136.jpg What Is Special About a Box Kite? A box kite looks like boxes in the sky. It has more sides than a flat kite. So what makes it special? Two open boxes, or cells, help a box kite stay very stable. https://socialmedia.xdme.com/tony/videos-book23/page-136.mp4 https://www.youtube.com/embed/udiUnq4biKk 118 2026-10-05T23:45:13+00:00 yes https://xdme.com/watch-book23-q137.html https://xdme.com/book23-thumbs/page-137.jpg How Do Stunt Kites Use Two Strings to Steer? Some kites have two strings. One in each hand. How do they steer so fast? Pulling the left line turns the kite left. Pulling the right line turns the kite right. https://socialmedia.xdme.com/tony/videos-book23/page-137.mp4 https://www.youtube.com/embed/KuH77Qv_SaM 111 2026-10-05T23:47:44+00:00 yes https://xdme.com/watch-book23-q138.html https://xdme.com/book23-thumbs/page-138.jpg How Can a Twisted Rubber Band Power a Tiny Airplane? A tiny plane has no battery. Just a twisted rubber band. So how does that power flight? Rubber-band planes were popular long before batteries were small enough for toys. https://socialmedia.xdme.com/tony/videos-book23/page-138.mp4 https://www.youtube.com/embed/IUPNgMe9tBk 119 2026-10-05T23:50:15+00:00 yes https://xdme.com/watch-book23-q139.html https://xdme.com/book23-thumbs/page-139.jpg How Can You Tell Which Way the Wind Is Blowing? Wind can be hard to see. But you can still find its path. How can you tell which way it blows? Flags, ribbons, smoke, or tall grass lean to show the wind. https://socialmedia.xdme.com/tony/videos-book23/page-139.mp4 https://www.youtube.com/embed/uu3Ks0shhOY 115 2026-10-05T23:53:17+00:00 yes https://xdme.com/watch-book23-q140.html https://xdme.com/book23-thumbs/page-140.jpg Why Does a Feather Fall More Slowly than a Coin? Drop a feather and a coin. The feather drifts, the coin zooms. Why is one so much slower? In a vacuum or on the Moon, a feather and a coin fall at the same speed. https://socialmedia.xdme.com/tony/videos-book23/page-140.mp4 https://www.youtube.com/embed/P2nDC14PApg 118 2026-10-05T23:55:48+00:00 yes https://xdme.com/watch-book23-q141.html https://xdme.com/book23-thumbs/page-141.jpg Why Do Phones Need Airplane Mode on a Plane? Phones talk to towers with radio signals. On a plane, those signals can cause trouble. So we switch on airplane mode! Airplane mode saves battery, too. https://socialmedia.xdme.com/tony/videos-book23/page-141.mp4 https://www.youtube.com/embed/DI-7wCCCFjo 127 2026-10-05T23:58:20+00:00 yes https://xdme.com/watch-book23-q142.html https://xdme.com/book23-thumbs/page-142.jpg Why Must Everyone Stay Far From a Spinning Propeller or a Running Jet Engine? Propellers and jet engines are very powerful. They can be dangerous up close. So everyone stays far away! Ground workers wear ear protection near jets. https://socialmedia.xdme.com/tony/videos-book23/page-142.mp4 https://www.youtube.com/embed/5QkCKmmAmiQ 124 2026-10-06T00:01:21+00:00 yes https://xdme.com/watch-book23-q143.html https://xdme.com/book23-thumbs/page-143.jpg Why Is Flying One of the Safest Ways to Travel? Flying is one of the safest ways to travel. That is no accident. Planes have many layers of safety! Mile for mile, airline travel is far safer than traveling by car. https://socialmedia.xdme.com/tony/videos-book23/page-143.mp4 https://www.youtube.com/embed/iNq7YETNJFo 125 2026-10-06T00:04:30+00:00 yes https://xdme.com/watch-book23-q144.html https://xdme.com/book23-thumbs/page-144.jpg What Jobs Help Planes Fly Besides Pilots? Pilots fly the plane. But they never work alone. A whole team helps every flight! A single flight can involve hundreds of people. Baggage handlers load the bags. https://socialmedia.xdme.com/tony/videos-book23/page-144.mp4 https://www.youtube.com/embed/hWKMTHMUomk 121 2026-10-06T00:07:01+00:00 yes https://xdme.com/watch-book23-q145.html https://xdme.com/book23-thumbs/page-145.jpg How Do Mechanics Keep Planes in Top Shape? Planes fly many hours every day. They need lots of care. Mechanics keep them in top shape! Some big checks take weeks. The plane is taken apart piece by piece. https://socialmedia.xdme.com/tony/videos-book23/page-145.mp4 https://www.youtube.com/embed/F5U-RGeLSjQ 118 2026-10-06T00:09:33+00:00 yes https://xdme.com/watch-book23-q146.html https://xdme.com/book23-thumbs/page-146.jpg Can a Balloon on a String Show How Thrust Works? A fan blows air one way. Put it on a toy cart. The cart rolls the other way! A push on the air makes an equal push on the fan in the other direction. https://socialmedia.xdme.com/tony/videos-book23/page-146.mp4 https://www.youtube.com/embed/1bMM3yRJNBA 123 2026-10-06T00:12:10+00:00 yes https://xdme.com/watch-book23-q147.html https://xdme.com/book23-thumbs/page-147.jpg How Can You Graph the Results of Your Flight Tests? You tested your paper planes. Now you have lots of numbers. A graph turns them into a picture! The first graphs were drawn more than two hundred years ago. https://socialmedia.xdme.com/tony/videos-book23/page-147.mp4 https://www.youtube.com/embed/27XgfFiSXVo 118 2026-10-06T00:15:17+00:00 yes https://xdme.com/watch-book23-q148.html https://xdme.com/book23-thumbs/page-148.jpg Why Can a Ring-Shaped Straw Glider Fly? A glider made from a straw and two paper rings? It does not look like a plane. But it really flies! Ring wings have been used in some real flying toys. https://socialmedia.xdme.com/tony/videos-book23/page-148.mp4 https://www.youtube.com/embed/kasKuzOOtPo 120 2026-10-06T00:17:48+00:00 yes https://xdme.com/watch-book23-q149.html https://xdme.com/book23-thumbs/page-149.jpg Which Sky Puzzles Are Engineers Still Working On? Planes are amazing already. But engineers want them even better. There are still sky puzzles to solve! Some researchers are testing planes shaped like a flying wing. https://socialmedia.xdme.com/tony/videos-book23/page-149.mp4 https://www.youtube.com/embed/eJGKI8ng7aw 122 2026-10-06T00:20:20+00:00 yes https://xdme.com/watch-book23-q150.html https://xdme.com/book23-thumbs/page-150.jpg What Should Every Young Pilot-In-Training Remember About Flight? Birds, planes, helicopters, and balloons all fly. They follow the same rules. Let us remember the big ones! Every flight, small or big, follows the same rules of physics. https://socialmedia.xdme.com/tony/videos-book23/page-150.mp4 https://www.youtube.com/embed/SsHqol9CjN4 118 2026-10-06T00:22:52+00:00 yes https://xdme.com/watch-book24-q001.html https://xdme.com/book24-thumbs/page-001.jpg What would you find if you dug a hole straight down? As you dig, you would pass through layers. First comes a thin top layer of dark, crumbly topsoil full of roots and tiny creatures. Under it is subsoil, which is lighter in color and has more clay and stones. Below that is broken rock, and then solid bedrock. https://socialmedia.xdme.com/tony/videos-book24/page-001.mp4 https://www.youtube.com/embed/vbF1AVYLE-s 119 2026-10-06T01:23:39+00:00 yes https://xdme.com/watch-book24-q002.html https://xdme.com/book24-thumbs/page-002.jpg What makes topsoil dark and crumbly? Topsoil is the top layer of soil where plants grow. It is dark because it holds a lot of rotted plant and animal bits mixed with tiny pieces of rock. This material feeds living things and helps the soil hold water. Worms, fungi, and bacteria mix everything together. https://socialmedia.xdme.com/tony/videos-book24/page-002.mp4 https://www.youtube.com/embed/vB9xthMl2tI 117 2026-10-06T01:54:22+00:00 yes https://xdme.com/watch-book24-q003.html https://xdme.com/book24-thumbs/page-003.jpg What is subsoil, the lighter layer below the topsoil? Subsoil sits under the topsoil. It has less rotted plant material, so it is lighter in color, often yellow, orange, or tan. It contains more clay and small stones, and it is harder and denser. Some deep roots reach down into it for water and minerals. https://socialmedia.xdme.com/tony/videos-book24/page-003.mp4 https://www.youtube.com/embed/JmeT5Kx0tGs 117 2026-10-06T01:57:23+00:00 yes https://xdme.com/watch-book24-q004.html https://xdme.com/book24-thumbs/page-004.jpg What is bedrock? Bedrock is the solid rock that lies beneath all the soil and loose stones. It may be only a few inches below the surface, or hundreds of feet down. Soil forms slowly as wind, water, ice, and roots break the top of the rock into smaller pieces. In some places, like along cliffs and mountains, you can see the bedrock itself. https://socialmedia.xdme.com/tony/videos-book24/page-004.mp4 https://www.youtube.com/embed/bKKhNKeCwXo 118 2026-10-06T02:00:36+00:00 yes https://xdme.com/watch-book24-q005.html https://xdme.com/book24-thumbs/page-005.jpg What is the deepest hole people have ever drilled? The Kola Superdeep Borehole in northern Russia reached about 7.6 miles down, after drilling on and off for almost 20 years. That is deeper than the deepest spot in the ocean, which is about 7 miles down. Yet it is just a pinprick in Earth, which is almost 4,000 miles from surface to center. The drill stopped because the rock was hotter and softer than expected. https://socialmedia.xdme.com/tony/videos-book24/page-005.mp4 https://www.youtube.com/embed/mvJO78HBv5g 121 2026-10-06T02:03:42+00:00 yes https://xdme.com/watch-book24-q006.html https://xdme.com/book24-thumbs/page-006.jpg Why does it get hotter the deeper you go underground? Earth's center is very hot, and its heat slowly flows outward. As you go deeper, you get closer to that heat. In most places, the temperature goes up by roughly 1 degree Fahrenheit for every 70 feet down. That is why deep mines need cooling and why the bottom of a very deep hole is so hot. https://socialmedia.xdme.com/tony/videos-book24/page-006.mp4 https://www.youtube.com/embed/yuU_PysLXdE 120 2026-10-06T02:06:43+00:00 yes https://xdme.com/watch-book24-q007.html https://xdme.com/book24-thumbs/page-007.jpg What is the water table? The water table is the upper edge of the ground that is completely soaked with water. Rain soaks into the soil and trickles down until it reaches a layer where all the little spaces are filled. Under that level, the ground is saturated. The water table goes up after heavy rain and down in dry seasons. https://socialmedia.xdme.com/tony/videos-book24/page-007.mp4 https://www.youtube.com/embed/E1u4mY6bsF8 115 2026-10-06T02:09:52+00:00 yes https://xdme.com/watch-book24-q008.html https://xdme.com/book24-thumbs/page-008.jpg Why does mud get so sticky and slippery? Mud is soil mixed with water. Clay and silt grains are so tiny that water coats each one in a thin film. A little water makes the grains cling to each other and to your boots. More water lets the grains slide past each other, so the mud turns slippery. https://socialmedia.xdme.com/tony/videos-book24/page-008.mp4 https://www.youtube.com/embed/ZU_Pu97UQik 116 2026-10-06T02:12:25+00:00 yes https://xdme.com/watch-book24-q009.html https://xdme.com/book24-thumbs/page-009.jpg What is the frost line, and why are pipes buried below it? In cold places, the ground freezes from the top down in winter. The frost line is the deepest point where the ground freezes. In southern Ontario it is about 4 feet down, and in colder parts of Canada it can be much deeper. Water pipes and building foundations are placed below that line, so freezing and expanding ice does not crack them. https://socialmedia.xdme.com/tony/videos-book24/page-009.mp4 https://www.youtube.com/embed/lgnjE1gfIY0 115 2026-10-06T02:15:37+00:00 yes https://xdme.com/watch-book24-q010.html https://xdme.com/book24-thumbs/page-010.jpg What is a pingo, a hill with an ice heart? A pingo is a round hill with a core of solid ice, found where the ground stays frozen. It forms when a shallow lake drains. The wet ground underneath freezes and swells, pushing the soil up into a dome. Near Tuktoyaktuk in the Northwest Territories there are more than 1,300 pingos. https://socialmedia.xdme.com/tony/videos-book24/page-010.mp4 https://www.youtube.com/embed/IQDO4KgTWs0 116 2026-10-06T02:18:43+00:00 yes https://xdme.com/watch-book24-q011.html https://xdme.com/book24-thumbs/page-011.jpg How can solid-looking ground hold both air and water? Soil looks solid, but it is full of tiny gaps called pores between its grains, a bit like a sponge. About half of the space in good soil is air and water. These spaces let roots breathe, let rainwater soak in, and give tiny animals room to move. If soil gets squashed, the gaps close up, and plants have a hard time growing. https://socialmedia.xdme.com/tony/videos-book24/page-011.mp4 https://www.youtube.com/embed/romc61zoEmg 117 2026-10-06T02:21:55+00:00 yes https://xdme.com/watch-book24-q012.html https://xdme.com/book24-thumbs/page-012.jpg Why is soil different colors in different places? Soil takes its color from what is in it. Dark brown or black soils have lots of rotted plant material. Red and orange soils get their color from iron that has rusted, like the red soil of Prince Edward Island. Gray or bluish soils are often soaked with water for long periods. https://socialmedia.xdme.com/tony/videos-book24/page-012.mp4 https://www.youtube.com/embed/Vkmk-0Z-oRc 115 2026-10-06T02:24:27+00:00 yes https://xdme.com/watch-book24-q013.html https://xdme.com/book24-thumbs/page-013.jpg Why does frozen ground push rocks up to the surface? When water in soil freezes, it expands and pushes the soil upward. This is called frost heave. When the ground thaws, the soil settles, but stones that were lifted do not drop back down exactly. Over many winters, rocks slowly work their way to the surface. https://socialmedia.xdme.com/tony/videos-book24/page-013.mp4 https://www.youtube.com/embed/_M9yGyeDsyg 118 2026-10-06T02:27:37+00:00 yes https://xdme.com/watch-book24-q014.html https://xdme.com/book24-thumbs/page-014.jpg Why does water sink through sand but sit on top of clay? Sand grains are large, so the gaps between them are wide and water drains quickly. Clay grains are tiny and flat, packed so tightly that the gaps are very small, and water passes through very slowly. That is why puddles last longer on clay soils and why gardeners add compost to improve drainage. Layers of clay can also hold underground water in place. https://socialmedia.xdme.com/tony/videos-book24/page-014.mp4 https://www.youtube.com/embed/qiT1fMOjoh0 120 2026-10-06T02:30:42+00:00 yes https://xdme.com/watch-book24-q015.html https://xdme.com/book24-thumbs/page-015.jpg Where does rainwater go when it soaks into the ground? Some rain runs along the surface into streams. Some soaks into the soil, where roots take it up or the soil holds it in tiny gaps. The rest keeps sinking through the layers until it joins the groundwater below. From there it moves slowly sideways through the rock and soil, and may return to a spring, a stream, or a lake. https://socialmedia.xdme.com/tony/videos-book24/page-015.mp4 https://www.youtube.com/embed/PwMKXurw1hc 114 2026-10-06T02:33:43+00:00 yes https://xdme.com/watch-book24-q016.html https://xdme.com/book24-thumbs/page-016.jpg Why does the ground sometimes sink to make a sinkhole? In some places, the rock under the soil is limestone or gypsum, which slowly dissolves in water. Over time, water can carve out empty spaces underground. When the roof of an empty space can no longer hold the weight above it, the ground sinks. Sinkholes can be small or large. https://socialmedia.xdme.com/tony/videos-book24/page-016.mp4 https://www.youtube.com/embed/e8oysf6rI6Y 124 2026-10-06T02:36:56+00:00 yes https://xdme.com/watch-book24-q017.html https://xdme.com/book24-thumbs/page-017.jpg Why is there always leftover dirt when you fill a hole back in? Soil in the ground is packed tightly. When you dig it up, the dirt becomes fluffy and takes up more space because it has more air in it. Then, when you put it back, it does not squash down into the same space. Also, the objects you took out, like rocks or roots, take up room. https://socialmedia.xdme.com/tony/videos-book24/page-017.mp4 https://www.youtube.com/embed/WdlS8Iga9oM 110 2026-10-06T02:39:27+00:00 yes https://xdme.com/watch-book24-q018.html https://xdme.com/book24-thumbs/page-018.jpg Why can you see stripes in a road cut or riverbank? The stripes are layers of sediment that built up in different periods. Each layer is made of different materials, such as sand, clay, or pebbles, and the colors reflect the minerals in them. Usually the oldest layers are at the bottom and the youngest at the top, unless the ground has been folded or tilted. Layers are like pages in the book of the ground. https://socialmedia.xdme.com/tony/videos-book24/page-018.mp4 https://www.youtube.com/embed/E7J6k_0SU8g 117 2026-10-06T02:42:40+00:00 yes https://xdme.com/watch-book24-q019.html https://xdme.com/book24-thumbs/page-019.jpg How long does it take to make an inch of topsoil? It takes a long time. Rocks break into tiny pieces by weathering, and then dead plants and animals mix in. In many places, making one inch of new topsoil takes hundreds of years. That is why it is important to protect soil from being washed or blown away. https://socialmedia.xdme.com/tony/videos-book24/page-019.mp4 https://www.youtube.com/embed/gMrXaJ1b9Fs 116 2026-10-06T02:45:13+00:00 yes https://xdme.com/watch-book24-q020.html https://xdme.com/book24-thumbs/page-020.jpg What happens to things we bury in the ground? Soil is full of tiny decomposers, like bacteria and fungi, that break down things that were once alive. A buried apple core can disappear in weeks or months. Paper and cotton may last longer. Metal slowly rusts. https://socialmedia.xdme.com/tony/videos-book24/page-020.mp4 https://www.youtube.com/embed/KlivLDraPGA 117 2026-10-06T02:48:16+00:00 yes https://xdme.com/watch-book24-q021.html https://xdme.com/book24-thumbs/page-021.jpg How can a jar of muddy water show the layers in soil? Put some soil in a jar of water, shake it, and let it settle. Sand sinks first because it is heavy, forming a layer on the bottom within a minute. Silt settles above it over several hours, and the tiniest clay particles take a day or more. You can see the three layers of soil particles. https://socialmedia.xdme.com/tony/videos-book24/page-021.mp4 https://www.youtube.com/embed/XLZ9Uj75obY 115 2026-10-06T02:51:30+00:00 yes https://xdme.com/watch-book24-q022.html https://xdme.com/book24-thumbs/page-022.jpg How deep does life go underground? Scientists have found tiny living things called microbes in rock more than 2 miles below Earth's surface. They live in cracks and pores, using chemicals from the rocks for energy instead of sunlight. They grow very slowly. This hidden world is called the deep biosphere. https://socialmedia.xdme.com/tony/videos-book24/page-022.mp4 https://www.youtube.com/embed/jDN_ghBKr_U 113 2026-10-06T02:54:48+00:00 yes https://xdme.com/watch-book24-q023.html https://xdme.com/book24-thumbs/page-023.jpg What is leaf litter, and what happens to it? Leaf litter is the loose layer of fallen leaves, twigs, and bits of bark on the forest floor. It protects the soil, keeps it moist, and shelters many small animals. Beetles, millipedes, and fungi break the litter down bit by bit. Over months and years, it turns into dark, crumbly material that mixes into the topsoil and feeds the trees. https://socialmedia.xdme.com/tony/videos-book24/page-023.mp4 https://www.youtube.com/embed/M-x_PTcTxnM 116 2026-10-09T14:43:24+00:00 yes https://xdme.com/watch-book24-q024.html https://xdme.com/book24-thumbs/page-024.jpg Why does the ground smell so fresh after rain? The smell has a name: petrichor. When raindrops hit dry soil, they trap tiny air bubbles that burst and send out a mist of smelly particles. Some of the smell comes from oils made by plants, and some comes from a chemical called geosmin that soil bacteria make. People can smell geosmin in very tiny amounts, perhaps because it signals water nearby. https://socialmedia.xdme.com/tony/videos-book24/page-024.mp4 https://www.youtube.com/embed/Bp0uE643qzo 119 2026-10-09T14:43:25+00:00 yes https://xdme.com/watch-book24-q025.html https://xdme.com/book24-thumbs/page-025.jpg Why is soil deep in some places and thin in others? Soil depth depends on how fast it forms and how fast it is carried away. On flat land with plenty of plants, soil builds up and gets thick. On steep slopes, rain and wind wash it away faster, leaving thin soil. Rivers also drop soil in their valleys. https://socialmedia.xdme.com/tony/videos-book24/page-025.mp4 https://www.youtube.com/embed/5oeV5JE06S8 114 2026-10-09T14:43:26+00:00 yes https://xdme.com/watch-book24-q026.html https://xdme.com/book24-thumbs/page-026.jpg How many living things can fit in a spoonful of soil? A spoonful of healthy soil can hold billions of bacteria, long threads of fungi, and thousands of other tiny creatures such as mites, microscopic worms, and springtails. Most of them are too small to see without a microscope. They eat dead leaves, each other, and bits of rock minerals. Together they make the soil alive and keep it healthy. https://socialmedia.xdme.com/tony/videos-book24/page-026.mp4 https://www.youtube.com/embed/qTIoukAJYOg 119 2026-10-09T14:43:27+00:00 yes https://xdme.com/watch-book24-q027.html https://xdme.com/book24-thumbs/page-027.jpg What is inside an ant nest? An ant nest is a maze of tunnels and rooms underground. There are chambers for the queen, for eggs and larvae, for storing food, and even for waste. Workers carry soil grains up through the tunnels, which makes the mound at the entrance. Some nests go several feet deep and house thousands of ants who share the work. https://socialmedia.xdme.com/tony/videos-book24/page-027.mp4 https://www.youtube.com/embed/bhggtn6XY18 107 2026-10-09T14:43:28+00:00 yes https://xdme.com/watch-book24-q028.html https://xdme.com/book24-thumbs/page-028.jpg How do ants get through the winter underground? When it gets cold, ants move deeper in their nests, below the frost line where the soil stays warmer. They slow down, gather in clusters, and eat food stored earlier or live off body fat. Their bodies work very slowly, so they need little energy. When spring warms the soil, the ants wake up and head back to the surface. https://socialmedia.xdme.com/tony/videos-book24/page-028.mp4 https://www.youtube.com/embed/ICGzf2V-bjU 108 2026-10-09T14:43:29+00:00 yes https://xdme.com/watch-book24-q029.html https://xdme.com/book24-thumbs/page-029.jpg Why do some cicadas spend 13 or 17 years underground? Periodical cicada nymphs live in the soil, feeding on sap from tree roots, for either 13 or 17 years. Then, all in the same year, they climb out, shed their skins, and become noisy adults. Emerging in huge numbers means predators can't eat them all. Scientists think prime numbers like 13 and 17 helped them avoid being on the same schedule as predators. https://socialmedia.xdme.com/tony/videos-book24/page-029.mp4 https://www.youtube.com/embed/iAwn6MbKmgE 120 2026-10-09T14:43:30+00:00 yes https://xdme.com/watch-book24-q030.html https://xdme.com/book24-thumbs/page-030.jpg What are grubs, and what do they become? A grub is a young beetle that looks like a fat, curved, creamy-white worm with a brown head and six small legs. Grubs live in the soil and munch on roots and decaying plants. After growing for months or even years, a grub forms a case and changes into an adult beetle, such as a June bug. Then it digs out and flies away. https://socialmedia.xdme.com/tony/videos-book24/page-030.mp4 https://www.youtube.com/embed/BCgzfsoObwo 109 2026-10-09T14:43:31+00:00 yes https://xdme.com/watch-book24-q031.html https://xdme.com/book24-thumbs/page-031.jpg How does a worm push through hard soil without legs? An earthworm has two sets of muscles. One squeezes it long and thin, and the other makes it short and fat. It reaches ahead with a pointed head, anchors itself with tiny bristles, then pulls the rest of its body forward. A slippery coat of mucus helps it slide. https://socialmedia.xdme.com/tony/videos-book24/page-031.mp4 https://www.youtube.com/embed/r-ZI772ViV0 111 2026-10-09T14:43:32+00:00 yes https://xdme.com/watch-book24-q032.html https://xdme.com/book24-thumbs/page-032.jpg How can a worm sense the world without eyes? Worms have no eyes, but their skin has special cells that sense light, so they can tell dark from bright. They also feel vibrations, touch, and chemicals. These senses help them avoid dry sunny spots and find food and mates. A worm's skin must stay damp, so it moves away from light and heat to stay safe. https://socialmedia.xdme.com/tony/videos-book24/page-032.mp4 https://www.youtube.com/embed/NZgvBNScj_4 108 2026-10-09T14:43:33+00:00 yes https://xdme.com/watch-book24-q033.html https://xdme.com/book24-thumbs/page-033.jpg What are nematodes, and where do they live? Nematodes are tiny roundworms, mostly smaller than a grain of salt. A handful of soil can contain thousands of them. Some eat bacteria or fungi, some eat other tiny animals, and a few feed on plant roots. Most are helpful, helping to recycle nutrients. https://socialmedia.xdme.com/tony/videos-book24/page-033.mp4 https://www.youtube.com/embed/m9PcTCbEENA 117 2026-10-09T14:43:34+00:00 yes https://xdme.com/watch-book24-q034.html https://xdme.com/book24-thumbs/page-034.jpg How do springtails jump when they have no wings? A springtail has a little tail-like part tucked under its belly, held in place like a spring. When it gets scared, the tail is released and flicks against the ground, flinging the springtail into the air in a flash. Springtails are tiny six-legged animals that live in soil and leaf litter. They eat fungi and rotting bits of leaves. https://socialmedia.xdme.com/tony/videos-book24/page-034.mp4 https://www.youtube.com/embed/IRAjo-yyvVE 111 2026-10-09T14:43:35+00:00 yes https://xdme.com/watch-book24-q035.html https://xdme.com/book24-thumbs/page-035.jpg How are millipedes different from centipedes? Millipedes have two pairs of legs on almost every body segment and move slowly. They eat rotting leaves and curl up when disturbed. Centipedes have only one pair of legs per segment and run fast. They hunt small prey like insects, using a pair of fangs. https://socialmedia.xdme.com/tony/videos-book24/page-035.mp4 https://www.youtube.com/embed/XGCwfrOYzSQ 120 2026-10-09T14:43:36+00:00 yes https://xdme.com/watch-book24-q036.html https://xdme.com/book24-thumbs/page-036.jpg What are pill bugs, and why do they curl into balls? Pill bugs, or roly-polies, are not insects. They are crustaceans, related to crabs and shrimp. They live in damp places like under logs and stones, because they breathe with gill-like parts that need to stay moist. When something bumps them, they roll up into a tight ball, which helps them stay safe. https://socialmedia.xdme.com/tony/videos-book24/page-036.mp4 https://www.youtube.com/embed/fCqWAM9-4Xg 109 2026-10-09T14:43:38+00:00 yes https://xdme.com/watch-book24-q037.html https://xdme.com/book24-thumbs/page-037.jpg Why do most animals that live in the soil see so poorly? Under the ground there is little to no light, so eyes are not very useful. Many soil animals rely on touch, smell, and vibrations instead. Their antennae and hairs pick up signals that eyes would miss. Using less energy for eyes means they can use it for other things. https://socialmedia.xdme.com/tony/videos-book24/page-037.mp4 https://www.youtube.com/embed/SY_6ol152aA 117 2026-10-09T14:43:39+00:00 yes https://xdme.com/watch-book24-q038.html https://xdme.com/book24-thumbs/page-038.jpg Do animals underground ever run out of air? Usually not. Soil is full of air-filled gaps, and fresh air seeps in from above. Many burrows have more than one entrance, which lets air move through them. Some animals, like prairie dogs, build mounds that act like chimneys to pull air through the tunnels. https://socialmedia.xdme.com/tony/videos-book24/page-038.mp4 https://www.youtube.com/embed/AwfKu42pYpg 109 2026-10-09T14:43:40+00:00 yes https://xdme.com/watch-book24-q039.html https://xdme.com/book24-thumbs/page-039.jpg How does a groundhog survive winter in its burrow? A groundhog eats a lot in the summer and fall to build up body fat. Then it goes into a deep burrow below the frost line and hibernates. Its heartbeat slows down to just a few beats a minute, and its body temperature drops close to that of the soil. It lives on stored fat until spring, when it wakes up and comes out. https://socialmedia.xdme.com/tony/videos-book24/page-039.mp4 https://www.youtube.com/embed/Giqs_OwJ2hg 109 2026-10-09T14:43:41+00:00 yes https://xdme.com/watch-book24-q040.html https://xdme.com/book24-thumbs/page-040.jpg How can some frogs and toads dig themselves into the ground? Spadefoot toads have hard, spade-shaped bumps on their hind feet. They wriggle backward and dig down into loose soil, sinking out of sight. Underground it is cooler and damper, so they can wait out dry weather or winter, sometimes for months. When heavy rains fall, they come up to breed. https://socialmedia.xdme.com/tony/videos-book24/page-040.mp4 https://www.youtube.com/embed/Zfojsm-9OGY 108 2026-10-09T14:43:43+00:00 yes https://xdme.com/watch-book24-q041.html https://xdme.com/book24-thumbs/page-041.jpg How can thousands of garter snakes share one winter den? In Manitoba, red-sided garter snakes gather in deep cracks and caverns in limestone, where it stays above freezing all winter. Tens of thousands share these dens. In spring, they crawl out in a huge wriggling crowd to find mates. These snakes are harmless to people. https://socialmedia.xdme.com/tony/videos-book24/page-041.mp4 https://www.youtube.com/embed/dH5wg1FhJxU 120 2026-10-09T14:43:44+00:00 yes https://xdme.com/watch-book24-q042.html https://xdme.com/book24-thumbs/page-042.jpg Why do so many kinds of bees nest in the ground? About seven out of ten bee species dig their nests in the soil. Each female digs a tunnel and makes little rooms stocked with pollen for her babies. They are usually not dangerous to people and do not live in big colonies. They look for bare, sunny patches of dry soil. https://socialmedia.xdme.com/tony/videos-book24/page-042.mp4 https://www.youtube.com/embed/rBczfEd_CZ4 113 2026-10-09T14:43:45+00:00 yes https://xdme.com/watch-book24-q043.html https://xdme.com/book24-thumbs/page-043.jpg How do animals find food in the dark ground? In the dark soil, animals use smell, taste, touch, and vibrations. A worm follows chemicals from decaying leaves. A beetle grub senses carbon dioxide given off by roots. A mole feels tiny movements with its snout. https://socialmedia.xdme.com/tony/videos-book24/page-043.mp4 https://www.youtube.com/embed/Ask5hrVzV_M 116 2026-10-09T14:43:46+00:00 yes https://xdme.com/watch-book24-q044.html https://xdme.com/book24-thumbs/page-044.jpg What do expert diggers' bodies have in common? Animals that dig, such as badgers, aardvarks, and armadillos, have strong front limbs, big claws, powerful shoulders, and short, sturdy bodies. Many have small ears and eyes that are protected from dirt. Their claws work like shovels, and their strong muscles power the digging. Engineers copy these designs to build digging machines. https://socialmedia.xdme.com/tony/videos-book24/page-044.mp4 https://www.youtube.com/embed/rCQB5c1GOSo 111 2026-10-09T14:43:48+00:00 yes https://xdme.com/watch-book24-q045.html https://xdme.com/book24-thumbs/page-045.jpg Why do many animals dig to escape heat and cold? A few feet underground, the temperature stays much steadier than the air above. It's cooler in summer and warmer in winter. Digging is a way for animals to avoid extremes without needing to travel far. Burrows also give shelter from wind, rain, and enemies. https://socialmedia.xdme.com/tony/videos-book24/page-045.mp4 https://www.youtube.com/embed/pPvgPT1CJyQ 117 2026-10-09T14:43:49+00:00 yes https://xdme.com/watch-book24-q046.html https://xdme.com/book24-thumbs/page-046.jpg What is a rabbit warren, and who lives in one? A warren is a network of connected burrows with many entrances and chambers. European rabbits dig these tunnels and live in groups. The mother digs a separate nursery burrow and lines it with soft fur and grass. Her babies stay inside for several weeks. https://socialmedia.xdme.com/tony/videos-book24/page-046.mp4 https://www.youtube.com/embed/3O_lZ7saQls 109 2026-10-09T14:43:50+00:00 yes https://xdme.com/watch-book24-q047.html https://xdme.com/book24-thumbs/page-047.jpg Why do prairie dogs build whole underground towns? Prairie dogs live in groups called coteries within big towns of tunnels. Their burrows have several chambers for sleeping, nursing, and storing food, and they have lookout mounds at the entrances. Sentries watch for danger and bark warnings. Prairie dogs also clip tall grass so they can see far. https://socialmedia.xdme.com/tony/videos-book24/page-047.mp4 https://www.youtube.com/embed/cBEnrDH2zoU 111 2026-10-09T14:43:51+00:00 yes https://xdme.com/watch-book24-q048.html https://xdme.com/book24-thumbs/page-048.jpg How do small insects survive the winter in the soil? Many insects hide in the soil or leaf litter during winter, where it does not get as cold. Some, like bumblebee queens, dig into the ground and sleep. Some lay eggs or form pupae that wait for spring. Others make natural antifreeze in their bodies. https://socialmedia.xdme.com/tony/videos-book24/page-048.mp4 https://www.youtube.com/embed/kTwz1IlpHK4 113 2026-10-09T14:43:52+00:00 yes https://xdme.com/watch-book24-q049.html https://xdme.com/book24-thumbs/page-049.jpg How can a funnel and a lamp show you what lives in soil? With a grown-up, put leaf litter in a funnel over a jar, with a screen to hold the litter. Shine a cool LED lamp above it. The litter slowly dries from the top, and tiny creatures move downward away from the light and dryness, falling into the jar. A magnifying glass lets you look at them. https://socialmedia.xdme.com/tony/videos-book24/page-049.mp4 https://www.youtube.com/embed/XzlQSj_lJH4 118 2026-10-09T14:43:53+00:00 yes https://xdme.com/watch-book24-q050.html https://xdme.com/book24-thumbs/page-050.jpg How do soil animals share food and recycle nutrients? In the soil, plants and animals that die become food. Bacteria and fungi break them down. Small animals like nematodes and mites eat the bacteria and fungi, and larger animals eat them in turn. At every step, some nutrients are released into the soil, where plant roots take them up again. https://socialmedia.xdme.com/tony/videos-book24/page-050.mp4 https://www.youtube.com/embed/ykmJjoahza4 115 2026-10-09T14:43:55+00:00 yes https://xdme.com/watch-book24-q051.html https://xdme.com/book24-thumbs/page-051.jpg What jobs do roots do for a plant? Roots have several jobs. They anchor the plant so wind and rain don't knock it over. They take in water and minerals from the soil. Many roots also store food, like sugar and starch, for later. https://socialmedia.xdme.com/tony/videos-book24/page-051.mp4 https://www.youtube.com/embed/tun_jxY6oMc 112 2026-10-09T14:43:56+00:00 yes https://xdme.com/watch-book24-q052.html https://xdme.com/book24-thumbs/page-052.jpg How do roots sense where gravity is pulling? Roots grow downward because of gravity. In the tip of each root are tiny, heavy grains called statoliths that settle to the low side of the cells. This tells the root which way is down, and the root bends that way. Shoots do the opposite and bend upward. https://socialmedia.xdme.com/tony/videos-book24/page-052.mp4 https://www.youtube.com/embed/-Wcoj4imyGU 112 2026-10-09T14:43:57+00:00 yes https://xdme.com/watch-book24-q053.html https://xdme.com/book24-thumbs/page-053.jpg How do roots find water in the soil? Roots can sense moisture. In drier soil, the tips bend toward the wetter side, which is called hydrotropism. They also grow more where there are nutrients and slow down in poor spots. Because roots spread out in many directions, they can discover pockets of water. https://socialmedia.xdme.com/tony/videos-book24/page-053.mp4 https://www.youtube.com/embed/eRsa2DX0qjo 113 2026-10-09T14:43:58+00:00 yes https://xdme.com/watch-book24-q054.html https://xdme.com/book24-thumbs/page-054.jpg What are root hairs, and why do roots have so many? Root hairs are tiny threadlike growths from a root's outer cells. They look like fuzz and are too small to see easily. Each hair soaks up water and minerals, and together they greatly increase the surface of a root. One plant can have billions. https://socialmedia.xdme.com/tony/videos-book24/page-054.mp4 https://www.youtube.com/embed/LlfcRFLiBoU 108 2026-10-09T14:43:59+00:00 yes https://xdme.com/watch-book24-q055.html https://xdme.com/book24-thumbs/page-055.jpg Why do roots grow around rocks instead of through them? A root tip is soft and cannot push through solid stone. When it touches a rock, it feels the pressure and bends away, growing along the easiest path toward soil that has water and air. Over many years, roots can still crack rocks by growing into small cracks and widening them as they thicken. Plants can shape the stones around them. https://socialmedia.xdme.com/tony/videos-book24/page-055.mp4 https://www.youtube.com/embed/pcfPhoPMXNY 108 2026-10-09T14:44:01+00:00 yes https://xdme.com/watch-book24-q056.html https://xdme.com/book24-thumbs/page-056.jpg What is the difference between a taproot and fibrous roots? A taproot is a single thick main root that goes straight down, like a carrot or a dandelion. It can reach deep water and store food. Fibrous roots are many thin roots that spread out in all directions, like those of grass. They hold the soil near the surface. https://socialmedia.xdme.com/tony/videos-book24/page-056.mp4 https://www.youtube.com/embed/Pfw0TOQ_0nk 114 2026-10-09T14:44:01+00:00 yes https://xdme.com/watch-book24-q057.html https://xdme.com/book24-thumbs/page-057.jpg Which vegetables are really roots? Carrots, beets, radishes, turnips, parsnips, and sweet potatoes are all storage roots. The plant stores sugar and starch in them to use later, such as when it flowers. People eat them for the same reason: they are full of energy. Potatoes and onions are not roots, though. https://socialmedia.xdme.com/tony/videos-book24/page-057.mp4 https://www.youtube.com/embed/sIKuJIQmlEE 113 2026-10-09T14:44:03+00:00 yes https://xdme.com/watch-book24-q058.html https://xdme.com/book24-thumbs/page-058.jpg How far do tree roots spread? Most tree roots are surprisingly shallow. The majority grow in the top foot or two of soil, where there is air, water, and nutrients. They spread outward, often two or three times wider than the branches above. A few deeper roots reach for water. https://socialmedia.xdme.com/tony/videos-book24/page-058.mp4 https://www.youtube.com/embed/A7L7hGLFL1s 110 2026-10-09T14:44:04+00:00 yes https://xdme.com/watch-book24-q059.html https://xdme.com/book24-thumbs/page-059.jpg Why do tree roots sometimes lift sidewalks and crack pipes? Roots grow where air and water are available, often right under the pavement. As they get thicker, they push up on the slab above them and can lift it. Roots can also slip into tiny cracks in pipes to reach water inside and then expand. Planners now give trees more room, choose trees with gentler roots, and use special materials to protect pipes. https://socialmedia.xdme.com/tony/videos-book24/page-059.mp4 https://www.youtube.com/embed/CFbSxbO8tjs 113 2026-10-09T14:44:06+00:00 yes https://xdme.com/watch-book24-q060.html https://xdme.com/book24-thumbs/page-060.jpg How do roots hold a hillside together? Roots work like thousands of tiny ropes tying the soil together. They make a net that holds soil in place and helps rainwater soak in instead of rushing downhill. That keeps the soil from sliding or washing into streams. After a forest is cut or a bank is bare, the soil can slip away quickly. https://socialmedia.xdme.com/tony/videos-book24/page-060.mp4 https://www.youtube.com/embed/52m9hSwtpWE 116 2026-10-09T14:44:07+00:00 yes https://xdme.com/watch-book24-q061.html https://xdme.com/book24-thumbs/page-061.jpg How long could the roots of one small plant stretch? In the 1930s, a scientist carefully washed the soil from one winter rye plant that had grown for four months. He measured over 380 miles of root, and billions of tiny root hairs. That is a bit farther than the distance from Toronto to Montreal. The roots were so many and so fine that they filled a lot of soil. https://socialmedia.xdme.com/tony/videos-book24/page-061.mp4 https://www.youtube.com/embed/6G1qmWvoNo4 113 2026-10-09T14:44:09+00:00 yes https://xdme.com/watch-book24-q062.html https://xdme.com/book24-thumbs/page-062.jpg What is a mycorrhiza, the partnership between roots and fungus? A mycorrhiza is a team-up between a plant root and a fungus. The fungus's threads wrap around or enter the root and spread far into the soil, reaching water and minerals like phosphorus that roots cannot reach. In return, the plant gives the fungus sugar that it makes using sunlight. About nine out of ten plant species form such partnerships. https://socialmedia.xdme.com/tony/videos-book24/page-062.mp4 https://www.youtube.com/embed/mYJZCBsm5Ow 121 2026-10-09T14:44:09+00:00 yes https://xdme.com/watch-book24-q063.html https://xdme.com/book24-thumbs/page-063.jpg What are the thin threads of a fungus that spread underground? The main body of most fungi is a mass of super-thin threads called mycelium. Each thread is much thinner than a hair, but together they form a web that spreads through soil, wood, and leaves. The threads release chemicals that break down dead material and then absorb the nutrients. In a teaspoon of forest soil, there may be miles of threads. https://socialmedia.xdme.com/tony/videos-book24/page-063.mp4 https://www.youtube.com/embed/Bsly24KIbYk 112 2026-10-09T14:44:11+00:00 yes https://xdme.com/watch-book24-q064.html https://xdme.com/book24-thumbs/page-064.jpg Do trees really share food through underground fungus networks? In some experiments, scientists, including Suzanne Simard in British Columbia, have found that carbon can move between trees through fungus threads. This idea is sometimes called the wood wide web. Some scientists think that big trees help seedlings in this way, while others think the effect may be smaller than first thought. It is an exciting question that researchers are still studying. https://socialmedia.xdme.com/tony/videos-book24/page-064.mp4 https://www.youtube.com/embed/KllSXRANuMc 118 2026-10-09T14:44:12+00:00 yes https://xdme.com/watch-book24-q065.html https://xdme.com/book24-thumbs/page-065.jpg How big can a single fungus grow? One of the largest living things is a honey fungus in an Oregon forest. Its threads spread under the soil across about 2,400 acres, about as big as 1,800 football fields, and it has been growing for thousands of years. You can only see the mushrooms in the fall. Most of its body stays hidden below. https://socialmedia.xdme.com/tony/videos-book24/page-065.mp4 https://www.youtube.com/embed/SeyyFHfCaWM 112 2026-10-09T14:44:13+00:00 yes https://xdme.com/watch-book24-q066.html https://xdme.com/book24-thumbs/page-066.jpg Why do mushrooms sometimes grow in a circle called a fairy ring? A fairy ring is a circle of mushrooms in a lawn or forest. It starts from one spot where a fungus grows underground from a single spore. The threads spread outward in every direction. The oldest threads in the middle die, so the living fungus is a growing ring, and mushrooms pop up along its edge. https://socialmedia.xdme.com/tony/videos-book24/page-066.mp4 https://www.youtube.com/embed/mgtFKRBEAjY 114 2026-10-09T14:44:14+00:00 yes https://xdme.com/watch-book24-q067.html https://xdme.com/book24-thumbs/page-067.jpg How do bean and pea roots get help from bacteria? Plants need nitrogen to grow, and the air is full of it, but plants can't use it as a gas. Beans, peas, and clover have little lumps on their roots called nodules, filled with helpful bacteria. The bacteria change nitrogen from the air into a form the plant can use, and the plant gives them sugar. Farmers plant these crops to enrich the soil. https://socialmedia.xdme.com/tony/videos-book24/page-067.mp4 https://www.youtube.com/embed/pAtzC9BIfOc 114 2026-10-09T14:44:15+00:00 yes https://xdme.com/watch-book24-q068.html https://xdme.com/book24-thumbs/page-068.jpg Is a potato a root? No, a potato is a tuber, a swollen underground stem that stores food for the plant. The little dents called eyes are buds that can sprout into new plants. If you plant a piece of potato with an eye, it will grow. Never eat green or sprouting parts of a potato, because they can make you sick. https://socialmedia.xdme.com/tony/videos-book24/page-068.mp4 https://www.youtube.com/embed/OaI5rHKgvUo 106 2026-10-09T14:44:17+00:00 yes https://xdme.com/watch-book24-q069.html https://xdme.com/book24-thumbs/page-069.jpg How do tulip and daffodil bulbs sleep through the cold? A bulb, such as a tulip or daffodil, is a bundle of thick, fleshy leaves wrapped around a tiny flower bud. It stores food and water through the cold winter, safe below the ground. When the soil warms in spring, the bulb uses its stored food to send up leaves and flowers quickly. That is why spring flowers pop up so early. https://socialmedia.xdme.com/tony/videos-book24/page-069.mp4 https://www.youtube.com/embed/2A60B94AguY 110 2026-10-09T14:44:18+00:00 yes https://xdme.com/watch-book24-q070.html https://xdme.com/book24-thumbs/page-070.jpg Why is it so hard to dig up grass that spreads underground? Many grasses have underground stems called rhizomes, which grow sideways below the surface. Along them, new shoots pop up. Even a small broken piece can grow into a new plant, so pulling one stem doesn't get rid of the plant. This is how grasses and some weeds spread so quickly. https://socialmedia.xdme.com/tony/videos-book24/page-070.mp4 https://www.youtube.com/embed/KQ-la4i69Xs 109 2026-10-09T14:44:19+00:00 yes https://xdme.com/watch-book24-q071.html https://xdme.com/book24-thumbs/page-071.jpg How can a forest of trees be one single living thing? Quaking aspens can grow new trunks from a single wide root system. A forest in Utah called Pando has about 47,000 trunks, all genetically identical and connected underground. Each trunk lives about a century, but the roots live much longer. Aspens on the Canadian prairies grow in clusters like this, too. https://socialmedia.xdme.com/tony/videos-book24/page-071.mp4 https://www.youtube.com/embed/R94fPBidgmg 113 2026-10-09T14:44:21+00:00 yes https://xdme.com/watch-book24-q072.html https://xdme.com/book24-thumbs/page-072.jpg Why can a cut-down tree stump grow new shoots? The roots still hold lots of stored food. If the stump and roots are alive, they can send up new shoots from buds near the base. This is called sprouting or suckering. Willows, poplars, and many other trees do it. https://socialmedia.xdme.com/tony/videos-book24/page-072.mp4 https://www.youtube.com/embed/I-GdunHVSjw 106 2026-10-09T14:44:22+00:00 yes https://xdme.com/watch-book24-q073.html https://xdme.com/book24-thumbs/page-073.jpg Why do prairie grasses have roots deeper than the plants are tall? Prairie grasses like big bluestem can have roots reaching 10 feet or more underground, while the tops reach only 6 feet or so. Deep roots find water during dry spells, and they hold soil in the wind. If fire or grazing eats the leaves, the grass regrows from its roots. Most of the plant is underground, safe and ready to grow again. https://socialmedia.xdme.com/tony/videos-book24/page-073.mp4 https://www.youtube.com/embed/VmP17_d-N9c 113 2026-10-09T14:44:23+00:00 yes https://xdme.com/watch-book24-q074.html https://xdme.com/book24-thumbs/page-074.jpg What is the rhizosphere, the busy zone around a root? The rhizosphere is the narrow zone of soil, only a few millimeters thick, around each root. Roots leak sugars and other chemicals into it, which attract bacteria and fungi. These microbes help the plant take in nutrients and may protect it from disease. It is one of the busiest places in the soil, like a tiny market town around the root. https://socialmedia.xdme.com/tony/videos-book24/page-074.mp4 https://www.youtube.com/embed/wTYv8p2e_UQ 108 2026-10-09T14:44:25+00:00 yes https://xdme.com/watch-book24-q075.html https://xdme.com/book24-thumbs/page-075.jpg How can scientists watch roots grow underground? Scientists use clear tubes, called minirhizotrons, put into the soil with tiny cameras inside. Some research stations have underground rooms with glass walls so that researchers can see roots through the window. At home, you can use a clear jar with a damp paper towel and a bean seed pressed against the glass. Roots grow right where you can see them. https://socialmedia.xdme.com/tony/videos-book24/page-075.mp4 https://www.youtube.com/embed/T0iVECIwjVk 112 2026-10-09T14:44:29+00:00 yes https://xdme.com/watch-book24-q076.html https://xdme.com/book24-thumbs/page-076.jpg How does an excavator dig so powerfully? An excavator is powered by liquid pushed through tubes. An engine runs a pump that squeezes oil, called hydraulic fluid, into cylinders. The oil pushes pistons that move the boom, the arm, and the bucket. Because liquids can't be squashed, a small push in the pump becomes a mighty push at the bucket. https://socialmedia.xdme.com/tony/videos-book24/page-076.mp4 https://www.youtube.com/embed/uWQROE0uuNc 116 2026-10-06T01:57:55+00:00 yes https://xdme.com/watch-book24-q077.html https://xdme.com/book24-thumbs/page-077.jpg How does a tunnel boring machine work? A tunnel boring machine, or TBM, is a giant tube with a spinning cutting wheel at the front. The wheel's hard metal discs grind through soil and rock. Conveyor belts carry the broken rubble out the back. Behind the cutter, the machine builds a ring of concrete pieces to line the walls, then pushes against it to move forward again. https://socialmedia.xdme.com/tony/videos-book24/page-077.mp4 https://www.youtube.com/embed/rUX7Vmh8pU4 113 2026-10-06T02:00:37+00:00 yes https://xdme.com/watch-book24-q078.html https://xdme.com/book24-thumbs/page-078.jpg What holds up the roof while a tunnel is being dug? Digging leaves an open space that could sag or collapse, so builders add support as they go. In hard rock, workers put long steel bolts into the ceiling and spray concrete on the walls. In soft ground, they use a strong shield and rings of concrete or steel. Engineers study the ground before digging to choose the right support. https://socialmedia.xdme.com/tony/videos-book24/page-078.mp4 https://www.youtube.com/embed/XxsUbFhqZ0s 106 2026-10-06T02:03:09+00:00 yes https://xdme.com/watch-book24-q079.html https://xdme.com/book24-thumbs/page-079.jpg How do workers get fresh air in a long tunnel? Digging a tunnel makes dust and engine fumes, so builders keep fresh air moving all the time. Huge fans push clean air through big tubes or duct pipes to the working end. Shafts, which are vertical holes to the surface, let stale air out. Sensors check the air for dust and harmful gases. https://socialmedia.xdme.com/tony/videos-book24/page-079.mp4 https://www.youtube.com/embed/DFj1RsCwBJs 110 2026-10-06T02:06:44+00:00 yes https://xdme.com/watch-book24-q080.html https://xdme.com/book24-thumbs/page-080.jpg How do builders dig a tunnel from both ends and meet in the middle? Surveyors measure everything very carefully, using lasers and satellites to mark the tunnel's exact path. Crews can then start digging from two sides, aiming at the same point. The Channel Tunnel between England and France was dug from both ends, and the two tunnels met with an error of only about one foot. Computers check the direction all along. https://socialmedia.xdme.com/tony/videos-book24/page-080.mp4 https://www.youtube.com/embed/d40TzgGmAss 114 2026-10-06T02:09:53+00:00 yes https://xdme.com/watch-book24-q081.html https://xdme.com/book24-thumbs/page-081.jpg How long can a tunnel be? The Gotthard Base Tunnel in Switzerland, a train tunnel, is about 35 miles long and goes under the Alps. The longest road tunnel, in Norway, is about 15 miles. Water tunnels can be even longer. One in New York is about 85 miles. https://socialmedia.xdme.com/tony/videos-book24/page-081.mp4 https://www.youtube.com/embed/ElzCvbbzxkw 118 2026-10-06T02:12:26+00:00 yes https://xdme.com/watch-book24-q082.html https://xdme.com/book24-thumbs/page-082.jpg How do builders make tunnels under rivers and seas? One method is to dig a trench in the river bottom and sink tunnel sections built on land. The sections float like boats and then are lowered and joined in the trench. The Detroit-Windsor Tunnel was built this way in 1930. For deeper crossings, tunnel boring machines can dig under the seabed, as in the Channel Tunnel, with watertight linings to keep the water out. https://socialmedia.xdme.com/tony/videos-book24/page-082.mp4 https://www.youtube.com/embed/MSekxYJOtnI 112 2026-10-06T02:15:39+00:00 yes https://xdme.com/watch-book24-q083.html https://xdme.com/book24-thumbs/page-083.jpg How did people dig tunnels before machines? For thousands of years, people used hand tools like picks, hammers, and baskets. In dry lands, builders dug long, gently sloping tunnels called qanats to bring water from hills to farms and towns. They dug shafts down from the surface to check the direction and to let air in and soil out. Some qanats still work after 2,000 years. https://socialmedia.xdme.com/tony/videos-book24/page-083.mp4 https://www.youtube.com/embed/vJt-TOVCl7Q 112 2026-10-06T02:18:12+00:00 yes https://xdme.com/watch-book24-q084.html https://xdme.com/book24-thumbs/page-084.jpg What is a mine? A mine is a place where people dig up useful materials from the ground. In an underground mine, shafts and tunnels reach deep into rock. In an open-pit mine, workers dig down from the surface in wide steps. A quarry is a kind of mine for stone and gravel. https://socialmedia.xdme.com/tony/videos-book24/page-084.mp4 https://www.youtube.com/embed/BcvLwY5cZCU 110 2026-10-06T02:21:14+00:00 yes https://xdme.com/watch-book24-q085.html https://xdme.com/book24-thumbs/page-085.jpg What useful things come out of mines? Mines give us iron for steel, copper for wires, aluminum from a rock called bauxite, nickel, gold, silver, and many more. They also give us salt, sand, gravel, and coal. A phone has dozens of different elements inside, many mined from the ground. Because mined materials are limited, recycling helps us use them wisely. https://socialmedia.xdme.com/tony/videos-book24/page-085.mp4 https://www.youtube.com/embed/GI5aOXeq1RE 112 2026-10-06T02:24:29+00:00 yes https://xdme.com/watch-book24-q086.html https://xdme.com/book24-thumbs/page-086.jpg How do miners reach a deep ore deposit? Miners dig a shaft, which is a vertical tunnel with a cage that works like an elevator, or a ramp that spirals downward for trucks. From the shaft, flat tunnels branch out to the rock that holds the ore. Geologists first drill small holes to take samples and map where the valuable rock is. Careful planning keeps digging safe and saves effort. https://socialmedia.xdme.com/tony/videos-book24/page-086.mp4 https://www.youtube.com/embed/qrzSQEuRCMY 108 2026-10-06T02:27:38+00:00 yes https://xdme.com/watch-book24-q087.html https://xdme.com/book24-thumbs/page-087.jpg How do mines stay safe for workers? Underground mines have many safety measures. Fans bring in fresh air and sensors test for gas. Workers wear hard hats, bright lamps, and special boots, and carry emergency air. Roofs are held up with bolts and steel mesh, and there are shelters stocked with supplies. https://socialmedia.xdme.com/tony/videos-book24/page-087.mp4 https://www.youtube.com/embed/1NASnOVV8U4 108 2026-10-06T02:30:10+00:00 yes https://xdme.com/watch-book24-q088.html https://xdme.com/book24-thumbs/page-088.jpg Why is there a giant salt mine under Lake Huron? About 400 million years ago, a shallow sea in this region dried up, leaving thick layers of salt that were later covered by rock. At Goderich, Ontario, workers dig this salt from about 1,800 feet below the ground, under the lake. It is one of the biggest salt mines in the world. Much of the salt is spread on icy roads in winter. https://socialmedia.xdme.com/tony/videos-book24/page-088.mp4 https://www.youtube.com/embed/QimyfYwVyVQ 112 2026-10-06T02:33:45+00:00 yes https://xdme.com/watch-book24-q089.html https://xdme.com/book24-thumbs/page-089.jpg Why do open-pit mines look like giant steps? In an open-pit mine, workers dig down in wide steps, called benches. This shape keeps the walls from collapsing and gives trucks a spiral road to drive up and down. As the pit gets deeper, the steps get smaller, making a shape like an upside-down cone. The biggest pits are miles wide and can be seen from space. https://socialmedia.xdme.com/tony/videos-book24/page-089.mp4 https://www.youtube.com/embed/G02Ku2g0o9I 109 2026-10-06T02:36:16+00:00 yes https://xdme.com/watch-book24-q090.html https://xdme.com/book24-thumbs/page-090.jpg Why are mining trucks so huge? A mine moves millions of tons of rock, so it needs trucks that carry as much as possible in one trip. The biggest haul trucks carry about 400 tons, which is more than the weight of 70 elephants. Their tires are about 13 feet tall, taller than a grown-up on another's shoulders. Their engines are powerful, and drivers sit high up in a cab. https://socialmedia.xdme.com/tony/videos-book24/page-090.mp4 https://www.youtube.com/embed/n1VVny7XcAM 113 2026-10-06T02:39:29+00:00 yes https://xdme.com/watch-book24-q091.html https://xdme.com/book24-thumbs/page-091.jpg How do we get metal out of rock? Ore is rock with a small amount of metal inside. First, the ore is crushed and ground into powder. Then, workers separate the metal-rich bits, sometimes by mixing the powder with water and soap-like chemicals so that metal specks stick to bubbles and float. Finally, factories heat the concentrate to melt out pure metal. https://socialmedia.xdme.com/tony/videos-book24/page-091.mp4 https://www.youtube.com/embed/aNL8XCPs5sg 114 2026-10-06T02:42:41+00:00 yes https://xdme.com/watch-book24-q092.html https://xdme.com/book24-thumbs/page-092.jpg Why is Sudbury, Ontario, famous for mining? About 1.85 billion years ago, a giant space rock hit what is now Sudbury and created a huge crater. The impact helped bring up rock rich in nickel and copper. Miners have dug these metals for over a century. Sudbury is known for the Big Nickel, a giant nickel coin statue, and for its science center, Science North. https://socialmedia.xdme.com/tony/videos-book24/page-092.mp4 https://www.youtube.com/embed/3YY3UjAil7s 117 2026-10-06T02:45:15+00:00 yes https://xdme.com/watch-book24-q093.html https://xdme.com/book24-thumbs/page-093.jpg How deep is the deepest mine in the world? The Mponeng gold mine in South Africa goes about 2.5 miles deep, which is about seven times taller than the CN Tower. The rock down there can be as hot as 140 degrees Fahrenheit, so the mine uses huge cooling plants and pumps ice slurry to keep workers comfortable. Elevators take the miners down in several steps. https://socialmedia.xdme.com/tony/videos-book24/page-093.mp4 https://www.youtube.com/embed/pXpP1IfIl78 118 2026-10-06T02:48:17+00:00 yes https://xdme.com/watch-book24-q094.html https://xdme.com/book24-thumbs/page-094.jpg How do miners break up hard rock? Miners drill rows of holes into the rock face. Trained blasting crews load them with carefully measured charges, clear everyone to a safe distance, and set them off. The rock splits along cracks into pieces that machines can lift. In softer rock, giant machines with spinning cutting drums can scrape off layers. https://socialmedia.xdme.com/tony/videos-book24/page-094.mp4 https://www.youtube.com/embed/ZSDO7A1Bhxc 112 2026-10-06T02:51:40+00:00 yes https://xdme.com/watch-book24-q095.html https://xdme.com/book24-thumbs/page-095.jpg Why do some cities build walkways underground? In cold, snowy places, underground walkways let people travel between buildings and subway stations without going outside. Toronto's PATH has about 19 miles of connected tunnels, with shops and cafés. Montreal has a similar network. They keep you warm, dry, and away from traffic. https://socialmedia.xdme.com/tony/videos-book24/page-095.mp4 https://www.youtube.com/embed/c1iD66a05LI 114 2026-10-06T02:54:59+00:00 yes https://xdme.com/watch-book24-q096.html https://xdme.com/book24-thumbs/page-096.jpg How do builders dig a deep basement without the sides caving in? Before digging, workers often drive strong steel beams or build concrete walls around the edge to hold back the soil. As they dig, they add braces across the hole. Pumps remove groundwater that would leak in. Trucks haul away the dirt on ramps. https://socialmedia.xdme.com/tony/videos-book24/page-096.mp4 https://www.youtube.com/embed/w76NbuQzB10 112 2026-10-09T14:44:33+00:00 yes https://xdme.com/watch-book24-q097.html https://xdme.com/book24-thumbs/page-097.jpg Why do root cellars keep food fresh? A root cellar is a room dug into the ground or a hillside. A few feet down, the temperature stays cool and steady all year, even when the weather above is freezing or hot. It is also dark and a bit damp, which keeps vegetables from drying out. Before refrigerators, people stored potatoes, carrots, apples, and canned food in root cellars all winter. https://socialmedia.xdme.com/tony/videos-book24/page-097.mp4 https://www.youtube.com/embed/94Vmx7eLfqs 115 2026-10-09T14:44:35+00:00 yes https://xdme.com/watch-book24-q098.html https://xdme.com/book24-thumbs/page-098.jpg Why do scientists build laboratories far underground? Some experiments hunt for super-rare tiny particles from space, such as neutrinos. Cosmic rays from space would swamp the detectors on the surface. Two kilometers of solid rock block most of them. SNOLAB in a Sudbury nickel mine is one such lab, about 6,800 feet down. https://socialmedia.xdme.com/tony/videos-book24/page-098.mp4 https://www.youtube.com/embed/Gb4hMGLF5qI 122 2026-10-09T14:44:36+00:00 yes https://xdme.com/watch-book24-q099.html https://xdme.com/book24-thumbs/page-099.jpg What is the tall tower over a mine called? The tower is called a headframe. It stands above the shaft and holds big wheels called sheaves. Cables run over the wheels to lift and lower the cage that carries people, or the skip that carries rock. A headframe is a bit like the frame of a giant pulley. https://socialmedia.xdme.com/tony/videos-book24/page-099.mp4 https://www.youtube.com/embed/KT5xTy2t3GI 106 2026-10-09T14:44:37+00:00 yes https://xdme.com/watch-book24-q100.html https://xdme.com/book24-thumbs/page-100.jpg How do pumps keep underground spaces dry? Water seeps through the rock and soil into mines and tunnels. If it was not removed, the spaces would flood. Workers dig small basins called sumps at low points, where the water collects, and powerful pumps send it up pipes to the surface. Builders also seal cracks and sometimes pump water out from the ground around a construction site before digging. https://socialmedia.xdme.com/tony/videos-book24/page-100.mp4 https://www.youtube.com/embed/2XRTXUApb-Q 107 2026-10-09T14:44:38+00:00 yes https://xdme.com/watch-book24-q101.html https://xdme.com/book24-thumbs/page-101.jpg What is peat, and how does it turn into coal? Peat is dark, spongy material made from partly rotted plants that pile up in wet bogs. Canada has huge peatlands. If peat is buried under layers of sand and mud for millions of years, heat and pressure squeeze out water and turn it into a softer brown coal, then into harder, black coal. Much of the world’s coal formed about 300 million years ago, before dinosaurs lived. https://socialmedia.xdme.com/tony/videos-book24/page-101.mp4 https://www.youtube.com/embed/dPDBTR9V6GA 118 2026-10-09T14:44:39+00:00 yes https://xdme.com/watch-book24-q102.html https://xdme.com/book24-thumbs/page-102.jpg Why do some oil wells stand out in the ocean? Some oil lies in rock far below the sea floor. To reach it, workers build an offshore platform that sits on legs or floats and is held in place by strong anchors. A drill runs down through the water and deep into the rock. Oil flows up through pipes to the platform and is carried away by ships or pipelines. https://socialmedia.xdme.com/tony/videos-book24/page-102.mp4 https://www.youtube.com/embed/4xANQj036bA 111 2026-10-09T14:44:41+00:00 yes https://xdme.com/watch-book24-q103.html https://xdme.com/book24-thumbs/page-103.jpg How do geologists find oil and gas hiding deep in the rock? Geologists send sound waves into the ground and listen for the echoes. The waves bounce back differently from different layers of rock, like the echo from a canyon wall. Computers turn the echoes into a picture of what lies below. They look for the shapes where oil and gas might be trapped. https://socialmedia.xdme.com/tony/videos-book24/page-103.mp4 https://www.youtube.com/embed/MoY22PnOGks 111 2026-10-09T14:44:41+00:00 yes https://xdme.com/watch-book24-q104.html https://xdme.com/book24-thumbs/page-104.jpg Why does oil stay trapped underground instead of floating to the top? Oil is lighter than water, so it slowly rises through tiny holes in rock until it hits a layer it cannot pass through, called cap rock. The oil collects in the porous rock below it, like water in a sponge under a plastic lid. A dome or fold in the rock makes a perfect trap. People drill through the cap rock to reach it. https://socialmedia.xdme.com/tony/videos-book24/page-104.mp4 https://www.youtube.com/embed/_JmH01iTFLo 115 2026-10-09T14:44:43+00:00 yes https://xdme.com/watch-book24-q105.html https://xdme.com/book24-thumbs/page-105.jpg How do fish that live in dark caves get by without eyes? Some fish live in caves where no light ever shines. Over many generations, cave-dwelling populations of some species, such as the Mexican tetra, have lost their eyes and most of their color, since seeing and color are no use there. They sense tiny water movements with special cells along their bodies, and they find food by smell and touch. Their bodies use less energy than fish that live in light. https://socialmedia.xdme.com/tony/videos-book24/page-105.mp4 https://www.youtube.com/embed/6iEyG98ekMg 118 2026-10-09T14:44:43+00:00 yes https://xdme.com/watch-book24-q106.html https://xdme.com/book24-thumbs/page-106.jpg How does the Oak Ridges Moraine soak up rain like a giant sponge? The Oak Ridges Moraine is a long ridge north of Toronto, built from sand and gravel that glaciers dropped about 12,000 years ago. Rain and melting snow soak through the loose layers and fill the spaces between the grains, which store water underground. That slowly leaks out as springs, which feed dozens of streams. The ridge acts like a giant water tank for the whole region. https://socialmedia.xdme.com/tony/videos-book24/page-106.mp4 https://www.youtube.com/embed/WQnZbdmVRg8 122 2026-10-09T14:44:44+00:00 yes https://xdme.com/watch-book24-q107.html https://xdme.com/book24-thumbs/page-107.jpg How does a well bring water up from underground? A well is a hole dug or drilled down below the water table. Water seeps in from the rock and soil. In old wells, people lowered a bucket on a rope. Today, a pump pushes or pulls the water up a pipe. https://socialmedia.xdme.com/tony/videos-book24/page-107.mp4 https://www.youtube.com/embed/n7JPYBEe1vs 105 2026-10-09T14:44:46+00:00 yes https://xdme.com/watch-book24-q108.html https://xdme.com/book24-thumbs/page-108.jpg What is an artesian well? An artesian well happens when water is trapped between two layers of tight rock and tilted so that it is under pressure. When a well is drilled into it, the pressure pushes the water up, sometimes all the way out of the ground without a pump. The pressure comes from the weight of water at the higher end, far away. The word comes from Artois in France. https://socialmedia.xdme.com/tony/videos-book24/page-108.mp4 https://www.youtube.com/embed/51rc3nedtpE 111 2026-10-09T14:44:47+00:00 yes https://xdme.com/watch-book24-q109.html https://xdme.com/book24-thumbs/page-109.jpg Where does the water in a spring come from? A spring is a place where groundwater flows out onto the surface. Rain and melting snow soak into the ground and move slowly downhill through cracks and spaces in the rock. Where a layer of clay or hard rock forces the water sideways, it can emerge on a hillside or at the foot of a slope. Spring water looks clear but is not always safe to drink, so never drink from a spring without a grown-up. https://socialmedia.xdme.com/tony/videos-book24/page-109.mp4 https://www.youtube.com/embed/f-_xVDRHo3w 114 2026-10-09T14:44:48+00:00 yes https://xdme.com/watch-book24-q110.html https://xdme.com/book24-thumbs/page-110.jpg Why do some wells run dry? Wells run dry when the water table drops below the bottom of the well. This can happen in a drought when little rain soaks in, or when more water is pumped out than gets refilled. The water table sinks, and shallow wells go dry first. People can dig deeper wells or save water. https://socialmedia.xdme.com/tony/videos-book24/page-110.mp4 https://www.youtube.com/embed/LLToPFpPmCE 109 2026-10-09T14:44:49+00:00 yes https://xdme.com/watch-book24-q111.html https://xdme.com/book24-thumbs/page-111.jpg Can a forked stick really find water underground? Some people walk around holding a forked stick, saying it dips down over water. This is called dowsing. When scientists test dowsers under careful conditions, they do no better than chance. The stick moves because of tiny, unconscious movements of the hands. https://socialmedia.xdme.com/tony/videos-book24/page-111.mp4 https://www.youtube.com/embed/LwMmvkIsH7I 112 2026-10-09T14:51:23+00:00 yes https://xdme.com/watch-book24-q112.html https://xdme.com/book24-thumbs/page-112.jpg How do veins of metal form in rock? Deep in Earth, hot water full of dissolved minerals moves through cracks in rock. As the water cools, the minerals come out of the water and build up on the walls of the crack, like the crust inside a kettle. Over thousands of years, the crack fills with minerals, which sometimes include gold, silver, or copper. That is called a vein. https://socialmedia.xdme.com/tony/videos-book24/page-112.mp4 https://www.youtube.com/embed/vMWTaMnek2Y 110 2026-10-09T14:51:23+00:00 yes https://xdme.com/watch-book24-q113.html https://xdme.com/book24-thumbs/page-113.jpg Why is gold found in streams? Gold is very heavy, about 19 times heavier than water, and does not rust. When rock containing gold wears away, streams carry the pieces along. Because gold is so heavy, it settles quickly in slow bends and behind rocks. Prospectors swirl gravel and water in a pan so that lighter sand washes away, and heavy gold stays. https://socialmedia.xdme.com/tony/videos-book24/page-113.mp4 https://www.youtube.com/embed/st2LnIgL0Jc 118 2026-10-09T14:51:25+00:00 yes https://xdme.com/watch-book24-q114.html https://xdme.com/book24-thumbs/page-114.jpg Why are there huge piles of sand and gravel in some places? Long ago, in the Ice Age, glaciers carried sand, gravel, and boulders over great distances. When the ice melted, it dropped them in piles and ridges. Meltwater rivers also washed and sorted the sand and gravel. Today, many of these deposits are dug out for roads and buildings. https://socialmedia.xdme.com/tony/videos-book24/page-114.mp4 https://www.youtube.com/embed/GicctSF1ln0 114 2026-10-09T14:51:26+00:00 yes https://xdme.com/watch-book24-q115.html https://xdme.com/book24-thumbs/page-115.jpg How can solid rock be made of tiny shells? Limestone is a rock made mostly from the shells and skeletons of sea creatures, such as corals, clams, and tiny plankton. They piled up on the seafloor for millions of years and were pressed into stone. Many limestone blocks contain fossils you can see. Tyndall stone from Manitoba, used in many buildings, is full of ancient sea animals. https://socialmedia.xdme.com/tony/videos-book24/page-115.mp4 https://www.youtube.com/embed/LA9rmfNrqOk 113 2026-10-09T14:51:28+00:00 yes https://xdme.com/watch-book24-q116.html https://xdme.com/book24-thumbs/page-116.jpg Where does the clay for bricks and pots come from? Clay forms when rocks break down into very fine, flat particles. It is dug from the ground in clay pits. When wet, it is soft and can be shaped, and when it's heated in a hot oven called a kiln, it hardens into brick, tile, or pottery. People have been making bricks and pots for thousands of years. https://socialmedia.xdme.com/tony/videos-book24/page-116.mp4 https://www.youtube.com/embed/GxQJ2OSN9VQ 111 2026-10-09T14:51:29+00:00 yes https://xdme.com/watch-book24-q117.html https://xdme.com/book24-thumbs/page-117.jpg Why is there a seed vault inside a frozen mountain? The Svalbard Global Seed Vault is a safe storage place dug into a mountain in the Arctic. It keeps backup copies of seeds from crops from around the world, in case a farm or seed bank loses its seeds. The cold, dry rooms are kept at about 0 degrees Fahrenheit, and the surrounding permafrost helps keep them chilled. Seeds can wait there for many years. https://socialmedia.xdme.com/tony/videos-book24/page-117.mp4 https://www.youtube.com/embed/pp4kH_kmSxo 113 2026-10-09T14:51:30+00:00 yes https://xdme.com/watch-book24-q118.html https://xdme.com/book24-thumbs/page-118.jpg What is a time capsule? A time capsule is a sealed container filled with items and buried or hidden to be opened in the future. People put in newspapers, photos, letters, and objects that show what life is like now. The container must be watertight so the contents stay safe underground. One famous capsule buried in 1939 is meant to stay shut until the year 6939. https://socialmedia.xdme.com/tony/videos-book24/page-118.mp4 https://www.youtube.com/embed/RbeGHkn9m-I 114 2026-10-09T14:51:31+00:00 yes https://xdme.com/watch-book24-q119.html https://xdme.com/book24-thumbs/page-119.jpg Why do old things get buried deeper over time? Over many years, dust, leaves, and soil build up on the ground. Earthworms also bring soil from below up to the surface in their castings. Charles Darwin spread chalk over a field, and decades later it lay several inches below the surface. A fraction of an inch a year adds up. https://socialmedia.xdme.com/tony/videos-book24/page-119.mp4 https://www.youtube.com/embed/plUpPzo8xD4 112 2026-10-09T14:51:32+00:00 yes https://xdme.com/watch-book24-q120.html https://xdme.com/book24-thumbs/page-120.jpg What causes a landslide, and what are the warning signs? A landslide happens when a slope of soil and rock slides downhill. Heavy rain, melting snow, or an earthquake can make the ground heavy and slippery. Tilted trees, new cracks in the ground, muddy springs, and falling pebbles can be warning signs. If you see them, move away to the side, not down the hill, and tell a grown-up. https://socialmedia.xdme.com/tony/videos-book24/page-120.mp4 https://www.youtube.com/embed/-oFUFz-qrUI 118 2026-10-09T14:51:33+00:00 yes https://xdme.com/watch-book24-q121.html https://xdme.com/book24-thumbs/page-121.jpg Why do basements feel cool and damp? A basement is surrounded by soil, which stays near the same cool temperature all year. The ground keeps the walls and floor cool. Moist air from outside condenses into tiny droplets on the cold surfaces, and water can seep through concrete from the ground. That is why basements often feel damp. https://socialmedia.xdme.com/tony/videos-book24/page-121.mp4 https://www.youtube.com/embed/QXjV__vKzoU 113 2026-10-09T14:51:34+00:00 yes https://xdme.com/watch-book24-q122.html https://xdme.com/book24-thumbs/page-122.jpg How does loose sand become solid sandstone? Sand that is buried deep under more layers gets squeezed by their weight. Water seeping through it carries dissolved minerals, such as silica or calcite, which fill the gaps between the grains. These minerals act like glue. Over millions of years, the loose sand turns into a hard rock. https://socialmedia.xdme.com/tony/videos-book24/page-122.mp4 https://www.youtube.com/embed/BDvRr9of6Yc 110 2026-10-09T14:51:36+00:00 yes https://xdme.com/watch-book24-q123.html https://xdme.com/book24-thumbs/page-123.jpg How do quarries cut big blocks of stone? A quarry is an open mine for stone. Workers use machines to drill lines of holes into a rock face and wire saws to cut big blocks free. Sometimes wedges split the rock along its natural cracks. Giant machines lift the blocks onto trucks. https://socialmedia.xdme.com/tony/videos-book24/page-123.mp4 https://www.youtube.com/embed/93OOT1xIHu4 111 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book24-q124.html https://xdme.com/book24-thumbs/page-124.jpg What else do we make from oil besides fuel? Oil is a mixture, and it can be separated into different parts. Some become gasoline, diesel, and jet fuel. Others are used to make plastics, asphalt for roads, wax, lubricants, and many fabrics. Even some medicines and cosmetics start from oil products. https://socialmedia.xdme.com/tony/videos-book24/page-124.mp4 https://www.youtube.com/embed/jzISDiBe3cI 113 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book24-q125.html https://xdme.com/book24-thumbs/page-125.jpg How can people use the ground's treasures wisely? Minerals, metals, and fuels in the ground take millions of years to form, so once they are gone, they are gone. People can use them wisely by saving energy, repairing and reusing things, and recycling metals and plastics. Mining companies can also clean up and plant trees or create parks when a mine is finished. Smart choices today help the future. https://socialmedia.xdme.com/tony/videos-book24/page-125.mp4 https://www.youtube.com/embed/DDMLY5vvu04 114 2026-10-09T14:51:39+00:00 yes https://xdme.com/watch-book24-q126.html https://xdme.com/book24-thumbs/page-126.jpg How can a machine see underground without digging? Ground-penetrating radar sends tiny pulses of radio waves into the ground and listens for echoes. When the waves hit something different, like a pipe, a buried wall, or a layer of rock, some bounce back. A computer turns the echoes into a picture. The machine looks like a small cart that is pushed along the ground, a bit like a lawn mower. https://socialmedia.xdme.com/tony/videos-book24/page-126.mp4 https://www.youtube.com/embed/yCyX_Vn0wSs 114 2026-10-09T14:51:40+00:00 yes https://xdme.com/watch-book24-q127.html https://xdme.com/book24-thumbs/page-127.jpg How can a tiny camera peek down a narrow hole? Scientists and well drillers lower a small waterproof camera on a cable into a borehole, which is a narrow hole drilled into the ground. A bright light on the camera shows the walls, cracks, water level, and layers of rock as it goes down. The pictures show up on a screen above. This lets them look at places that no person could ever fit into. https://socialmedia.xdme.com/tony/videos-book24/page-127.mp4 https://www.youtube.com/embed/2sEpPynINfI 108 2026-10-09T14:54:41+00:00 yes https://xdme.com/watch-book24-q128.html https://xdme.com/book24-thumbs/page-128.jpg How do scientists take a core sample of soil? A soil corer is a hollow metal tube that is pushed or hammered into the ground. When it is pulled out, it holds a column of soil with all the layers in order. Scientists look at the colors, the texture, and the roots in each layer. It is a fast way to study the ground without digging a big hole. https://socialmedia.xdme.com/tony/videos-book24/page-128.mp4 https://www.youtube.com/embed/UT6z4Gqo7rs 109 2026-10-09T14:55:18+00:00 yes https://xdme.com/watch-book24-q129.html https://xdme.com/book24-thumbs/page-129.jpg How do archaeologists map a dig site? Before digging, archaeologists mark off the site in a grid of squares using string and stakes. They dig each square a little at a time, record the depth, and take photos and notes of everything they find. Soil is sifted through screens to catch tiny pieces. Knowing exactly where each object was found helps them figure out its story. https://socialmedia.xdme.com/tony/videos-book24/page-129.mp4 https://www.youtube.com/embed/iJ0ORRHI9ZE 115 2026-10-09T14:55:19+00:00 yes https://xdme.com/watch-book24-q130.html https://xdme.com/book24-thumbs/page-130.jpg What happens to a fragile artifact after it comes out of the ground? Once an artifact is dug up, air and light can start to damage it. Archaeologists brush off the soil gently, take photos, and note exactly where it was found. They wrap it in soft foam and send it to a lab. Conservators clean it, and they keep old wood wet until it can be treated so it will not crack. https://socialmedia.xdme.com/tony/videos-book24/page-130.mp4 https://www.youtube.com/embed/NCn-H7oUInw 116 2026-10-09T14:55:20+00:00 yes https://xdme.com/watch-book24-q131.html https://xdme.com/book24-thumbs/page-131.jpg Why must crews call before they dig? Underground, there are pipes for water and gas, electric cables, and phone and internet lines, and hitting one by mistake can be dangerous. Before digging, workers call a free service. Locators mark the lines with colored paint and flags: red for electric, yellow for gas, blue for water, and orange for communications. Everyone then knows where to avoid digging. https://socialmedia.xdme.com/tony/videos-book24/page-131.mp4 https://www.youtube.com/embed/h2lNv80Ay4E 119 2026-10-09T14:55:21+00:00 yes https://xdme.com/watch-book24-q132.html https://xdme.com/book24-thumbs/page-132.jpg What is humus, the dark crumbly part of soil? Humus is the dark, crumbly material that forms when dead leaves, roots, and animal bodies break down for a long time. It soaks up water like a sponge, holds nutrients that plants need, and makes heavy soil looser and sandy soil better at holding water. Earthworms, fungi, and bacteria turn the scraps into humus. A handful of humus-rich soil smells earthy and sweet. https://socialmedia.xdme.com/tony/videos-book24/page-132.mp4 https://www.youtube.com/embed/KVN-FpLeWgU 109 2026-10-09T14:55:22+00:00 yes https://xdme.com/watch-book24-q133.html https://xdme.com/book24-thumbs/page-133.jpg How can you tell what kind of soil you have just by squeezing it? Moisten a handful of soil and squeeze. Sandy soil feels gritty and falls apart. Silty soil feels smooth like flour. Clay soil feels sticky and can be rolled into a ribbon. https://socialmedia.xdme.com/tony/videos-book24/page-133.mp4 https://www.youtube.com/embed/HJGds1YgcVs 108 2026-10-09T14:55:23+00:00 yes https://xdme.com/watch-book24-q134.html https://xdme.com/book24-thumbs/page-134.jpg How can scientists tell if soil is thirsty or soaked? Farmers and scientists push probes into the ground that measure how easily electricity moves through the soil. Wet soil carries more than dry soil, so the probe can tell the moisture level. Satellites can even measure moisture across whole regions using microwaves. This helps people know when to water crops and to prepare for floods and droughts. https://socialmedia.xdme.com/tony/videos-book24/page-134.mp4 https://www.youtube.com/embed/q65ybu_kv7M 115 2026-10-09T14:55:24+00:00 yes https://xdme.com/watch-book24-q135.html https://xdme.com/book24-thumbs/page-135.jpg How can dogs find food that grows underground? Truffles are fungi that grow underground near tree roots. They give off a strong smell that dogs can detect from far away. Trained dogs and their handlers walk through woods, and when a dog catches the scent, it paws or sits to show where to dig. A good nose is a wonderful tool, since dogs can smell far better than people. https://socialmedia.xdme.com/tony/videos-book24/page-135.mp4 https://www.youtube.com/embed/kMDHlmHgCZ4 106 2026-10-09T14:55:25+00:00 yes https://xdme.com/watch-book24-q136.html https://xdme.com/book24-thumbs/page-136.jpg How do scientists count the creatures living in the ground? Scientists mark a square patch of soil, dig out the top layer, and gently sort through it by hand, counting worms and insects. Another method is to bury a small cup so its top is level with the ground. Creatures that walk by fall in, and are counted and released. By repeating the counts through the year, scientists learn how soil life changes. https://socialmedia.xdme.com/tony/videos-book24/page-136.mp4 https://www.youtube.com/embed/_pz9p6-RiGQ 108 2026-10-09T14:55:26+00:00 yes https://xdme.com/watch-book24-q137.html https://xdme.com/book24-thumbs/page-137.jpg Can scientists listen to life in the soil? Yes. Researchers push tiny microphones into the ground and record rustling, scratching, and clicking sounds made by worms, beetles, ants, and other tiny animals. They found that healthy soil is noisier, and poor soil is quieter. Listening is a gentle way to study soil without disturbing it. https://socialmedia.xdme.com/tony/videos-book24/page-137.mp4 https://www.youtube.com/embed/51q-FKAFk1o 114 2026-10-09T14:55:27+00:00 yes https://xdme.com/watch-book24-q138.html https://xdme.com/book24-thumbs/page-138.jpg How does carbon dating tell the age of buried wood or bones? All living things take in a tiny amount of a special kind of carbon called carbon-14. When they die, they stop taking in more, and the carbon-14 they have slowly fades away at a steady rate. Half of it is gone after 5,730 years. By measuring what is left, scientists can work out how long ago something died. https://socialmedia.xdme.com/tony/videos-book24/page-138.mp4 https://www.youtube.com/embed/IzSh-6cNMmk 122 2026-10-09T14:55:28+00:00 yes https://xdme.com/watch-book24-q139.html https://xdme.com/book24-thumbs/page-139.jpg What secrets can a drilled rock core hold? A rock core is a long cylinder drilled out of deep rock. It shows layers like pages in a book. Scientists look at the minerals, tiny fossils, and chemical clues to learn the age of the rock and what the world was like when it formed. Miners use cores to find where valuable rock lies. https://socialmedia.xdme.com/tony/videos-book24/page-139.mp4 https://www.youtube.com/embed/whJTJiEPi4I 110 2026-10-09T14:55:29+00:00 yes https://xdme.com/watch-book24-q140.html https://xdme.com/book24-thumbs/page-140.jpg Why do ghostly lines show up in dry grass or crops? Buried stone walls or roads make the soil shallow above them, so plants dry out faster and turn yellow. Buried ditches hold more water, so plants above them grow greener and taller. From the air, these differences make faint lines called crop marks that reveal outlines of old buildings and forts. Archaeologists use the clues to decide where to dig. https://socialmedia.xdme.com/tony/videos-book24/page-140.mp4 https://www.youtube.com/embed/o0lfqrUneVg 115 2026-10-09T14:55:31+00:00 yes https://xdme.com/watch-book24-q141.html https://xdme.com/book24-thumbs/page-141.jpg Why should you never go into an old well, mine, or tunnel? Old underground places can be dangerous. The walls and roof may be weak and could fall, the air may not have enough oxygen, and there may be hidden drops or water. They are often hard to get out of. Even experts go in only with training, equipment, and a plan. https://socialmedia.xdme.com/tony/videos-book24/page-141.mp4 https://www.youtube.com/embed/l3FUNRORdwQ 108 2026-10-09T14:55:32+00:00 yes https://xdme.com/watch-book24-q142.html https://xdme.com/book24-thumbs/page-142.jpg Why can a deep hole in the sand cave in? Dry or wet sand has no glue to hold the grains together, so the walls of a hole can slump. Sand is also heavy, and a collapse can trap a person. Keep holes at the beach or sandbox small, no deeper than your knees, and never dig tunnels. Always fill your hole in before you leave, so others and animals can't trip. https://socialmedia.xdme.com/tony/videos-book24/page-142.mp4 https://www.youtube.com/embed/y5N4-8BoofU 108 2026-10-09T14:55:33+00:00 yes https://xdme.com/watch-book24-q143.html https://xdme.com/book24-thumbs/page-143.jpg Why can squished soil make it hard for plants to grow? Heavy machines, feet, and tires press soil grains tightly together and squeeze out the air gaps. Roots can't push through hard soil, water runs off instead of soaking in, and soil animals have no room to move. This is called compaction. You can help by staying on paths and by adding compost to loosen soil. https://socialmedia.xdme.com/tony/videos-book24/page-143.mp4 https://www.youtube.com/embed/5wpyCB0h02o 106 2026-10-09T14:55:34+00:00 yes https://xdme.com/watch-book24-q144.html https://xdme.com/book24-thumbs/page-144.jpg How can people stop soil from washing or blowing away? Bare soil is easily carried away by rain and wind, which is called erosion. People protect it with plants and mulch. Roots hold the soil, and leaves soften raindrops. Farmers plant cover crops, leave stalks in fields, and plant rows of trees as windbreaks. https://socialmedia.xdme.com/tony/videos-book24/page-144.mp4 https://www.youtube.com/embed/b-vnz6fnfAA 114 2026-10-09T14:55:35+00:00 yes https://xdme.com/watch-book24-q145.html https://xdme.com/book24-thumbs/page-145.jpg How can we protect the water hidden in the ground? Groundwater can be polluted by things that soak in from above. People protect it by never pouring paint, oil, or chemicals on the ground or down drains, by taking them to special collection sites, and by sealing old wells. Using less road salt and fixing leaky tanks also helps. Because groundwater moves slowly, mistakes can last a long time. https://socialmedia.xdme.com/tony/videos-book24/page-145.mp4 https://www.youtube.com/embed/lT1LtWJFQas 114 2026-10-09T14:55:36+00:00 yes https://xdme.com/watch-book24-q146.html https://xdme.com/book24-thumbs/page-146.jpg How do people heal land after a mine closes? When a mine is finished, workers can fill holes, reshape the land, and add fresh soil. Then they plant grasses and trees. Around Sudbury, Ontario, millions of trees have been planted since the 1970s, and lakes and forests have come back. Near Victoria, British Columbia, an old quarry became the Butchart Gardens. https://socialmedia.xdme.com/tony/videos-book24/page-146.mp4 https://www.youtube.com/embed/nlahLx2Nn8Q 114 2026-10-09T14:55:37+00:00 yes https://xdme.com/watch-book24-q147.html https://xdme.com/book24-thumbs/page-147.jpg What goes in an underground detective kit? A good soil-detective kit has a magnifying glass, a small trowel (used with a grown-up's help), jars, a ruler, a notebook, and a thermometer. Add a bit of string for marking squares, plain paper, and a pencil. Wear gloves for digging, and wash your hands afterward. Always get permission before you dig, and leave places as you found them. https://socialmedia.xdme.com/tony/videos-book24/page-147.mp4 https://www.youtube.com/embed/2A0maz2llRc 114 2026-10-09T14:58:39+00:00 yes https://xdme.com/watch-book24-q148.html https://xdme.com/book24-thumbs/page-148.jpg Who works with the ground for a living? Geologists study rocks, and hydrogeologists study groundwater. Soil scientists look at the ground and plants. Tunnel engineers and miners dig. Archaeologists uncover the past. https://socialmedia.xdme.com/tony/videos-book24/page-148.mp4 https://www.youtube.com/embed/NEz38JvfDxU 113 2026-10-09T15:01:40+00:00 yes https://xdme.com/watch-book24-q149.html https://xdme.com/book24-thumbs/page-149.jpg What puzzles about the ground are scientists still chasing? Scientists still do not know how many kinds of living things live in soil, because most are tiny and unstudied. They are curious about how deep life reaches and how fungus networks really share things. They also wonder what other minerals and water lie hidden deep underground. Every new tool, from radar to microphones, reveals new surprises. https://socialmedia.xdme.com/tony/videos-book24/page-149.mp4 https://www.youtube.com/embed/rxkOtfhluCw 112 2026-10-09T15:01:41+00:00 yes https://xdme.com/watch-book24-q150.html https://xdme.com/book24-thumbs/page-150.jpg What is the big story of the world beneath our feet? Under every step you take is a hidden world. There are layers of soil and rock, water seeping through, roots and fungi tied together, and countless tiny animals at work. People dig tunnels, mines, and wells to use its treasures, and scientists use clever tools to explore it. If we take care of the ground, it will keep supporting us and all life. https://socialmedia.xdme.com/tony/videos-book24/page-150.mp4 https://www.youtube.com/embed/_UFZG75-Ww8 113 2026-10-09T15:01:42+00:00 yes https://xdme.com/watch-book25-q001.html https://xdme.com/book25-thumbs/page-001.jpg What happens on a building site before the first floor goes up? Before building a skyscraper, engineers drill test holes to learn what the soil and rock are like. Then crews dig a giant hole and haul away the dirt. Next, they build the foundation. Many towers stand on huge concrete columns called piles that reach deep into the ground, so the weight of the tower is held safely. Only after this hidden work can the building start to rise. https://socialmedia.xdme.com/tony/videos-book25/page-001.mp4 https://www.youtube.com/embed/euWV_G4Dtoo 112 2026-10-09T14:43:26+00:00 yes https://xdme.com/watch-book25-q002.html https://xdme.com/book25-thumbs/page-002.jpg Why do tall buildings have a steel skeleton? A skyscraper's strength comes from a frame of steel columns and beams, like a skeleton. The frame carries the weight of the floors, walls, and people down to the foundation. Steel is strong and can bend a little without breaking, which helps in wind. The walls hang from the frame, so they can be thin and light. https://socialmedia.xdme.com/tony/videos-book25/page-002.mp4 https://www.youtube.com/embed/yDNraCs8K8M 109 2026-10-09T14:43:27+00:00 yes https://xdme.com/watch-book25-q003.html https://xdme.com/book25-thumbs/page-003.jpg When was the first skyscraper built? Many people call the Home Insurance Building in Chicago, finished in 1885 with ten stories, the first skyscraper. It used a frame of iron and steel, which let buildings grow much taller than thick brick walls could. Safe elevators, invented earlier, made people willing to use tall buildings. Soon cities across the world were reaching up. https://socialmedia.xdme.com/tony/videos-book25/page-003.mp4 https://www.youtube.com/embed/4esRwNlBbY8 113 2026-10-09T14:43:28+00:00 yes https://xdme.com/watch-book25-q004.html https://xdme.com/book25-thumbs/page-004.jpg How tall is the tallest building in the world? The Burj Khalifa in Dubai is the tallest building in the world. It is 2,717 feet tall, with 163 floors, about twice as tall as the Empire State Building in New York. It tapers as it rises, and from the top you can see for many miles. Engineers had to design it carefully for wind and for very hot weather. https://socialmedia.xdme.com/tony/videos-book25/page-004.mp4 https://www.youtube.com/embed/yT1hpyqWjAk 113 2026-10-09T14:43:29+00:00 yes https://xdme.com/watch-book25-q005.html https://xdme.com/book25-thumbs/page-005.jpg How does a tower crane grow taller as the building grows? A tower crane stands on a tall mast. To climb higher, a special frame slips around the mast, lifts the top section of the crane, and lets workers slide a new piece of mast into the gap. The crane then rests on its taller mast. A counterweight at the back balances the load being lifted at the front. Operators work from a cab or by remote. https://socialmedia.xdme.com/tony/videos-book25/page-005.mp4 https://www.youtube.com/embed/xjpid4XAqp4 114 2026-10-09T14:43:30+00:00 yes https://xdme.com/watch-book25-q006.html https://xdme.com/book25-thumbs/page-006.jpg How does concrete get to the top of a tall building? Concrete is brought by trucks with spinning drums that keep it mixed so it will not harden. At the building, a powerful pump pushes it through steel pipes all the way up, sometimes hundreds of feet. Workers pour it into frames called forms and let it harden around steel bars. At the Burj Khalifa, concrete was pumped to nearly 2,000 feet. https://socialmedia.xdme.com/tony/videos-book25/page-006.mp4 https://www.youtube.com/embed/vTjq_I1R4BQ 111 2026-10-09T14:43:31+00:00 yes https://xdme.com/watch-book25-q007.html https://xdme.com/book25-thumbs/page-007.jpg Why can a skyscraper have walls made mostly of glass? In a skyscraper, the steel frame holds the weight, so the outer walls do not have to. The glass panels simply hang from the frame like curtains, which is why they are called curtain walls. The glass can have thin coatings and layers of air to keep heat in or out. Big windows let in daylight and give people great views. https://socialmedia.xdme.com/tony/videos-book25/page-007.mp4 https://www.youtube.com/embed/63zqGeqWBnU 109 2026-10-09T14:43:33+00:00 yes https://xdme.com/watch-book25-q008.html https://xdme.com/book25-thumbs/page-008.jpg How does the golden ball inside Taipei 101 keep the tower steady? Some tall buildings sway a little in strong winds. Taipei 101 in Taiwan has a huge golden steel ball, about 18 feet wide and weighing about 660 tons, hanging from cables inside the tower. When wind pushes the building one way, the ball swings the other way and cancels part of the motion. Giant shock absorbers slow the ball. This kind of weight is called a tuned mass damper. Visitors can see it. https://socialmedia.xdme.com/tony/videos-book25/page-008.mp4 https://www.youtube.com/embed/Fb87WDOYqJE 122 2026-10-09T14:43:34+00:00 yes https://xdme.com/watch-book25-q009.html https://xdme.com/book25-thumbs/page-009.jpg Why do skyscrapers have metal rods on top? Tall buildings are likely to be hit by lightning. A metal rod at the top, called a lightning rod, gives lightning a safe path. Thick cables connect it to the ground, so the electricity flows around the building and into the earth. Benjamin Franklin invented the lightning rod in the 1700s. The Empire State Building is struck about twenty times a year. https://socialmedia.xdme.com/tony/videos-book25/page-009.mp4 https://www.youtube.com/embed/Yw30fNOL89w 111 2026-10-09T14:43:35+00:00 yes https://xdme.com/watch-book25-q010.html https://xdme.com/book25-thumbs/page-010.jpg How do elevator brakes and floor sensors keep riders safe? An elevator has several safety systems. A speed governor watches how fast the car moves, and if the car goes too fast, safety clamps squeeze the steel rails along the shaft and stop it. Sensors and a computer track which floor you are on and stop the car at the right place. Door sensors stop the doors from closing on people. Inspectors check elevators regularly. https://socialmedia.xdme.com/tony/videos-book25/page-010.mp4 https://www.youtube.com/embed/OGUk9RlHOi8 113 2026-10-09T14:43:36+00:00 yes https://xdme.com/watch-book25-q011.html https://xdme.com/book25-thumbs/page-011.jpg How do tall buildings stay safe from fire? Tall buildings have many layers of fire safety. Sprinklers spray water when heat is detected, and alarms warn people. Steel is covered with a fireproof coating, because steel gets weak when very hot. Fire doors and strong stairwells give people a safe way to leave. People should use the stairs, not the elevators, in a fire. Practicing fire drills helps everyone know what to do. https://socialmedia.xdme.com/tony/videos-book25/page-011.mp4 https://www.youtube.com/embed/j9-L84jA9As 113 2026-10-09T14:43:37+00:00 yes https://xdme.com/watch-book25-q012.html https://xdme.com/book25-thumbs/page-012.jpg What makes the CN Tower in Toronto so special? The CN Tower was finished in 1976 and stands 1,815 feet tall. For over 30 years it was the tallest free-standing structure in the world. It is used for TV and radio signals, and visitors can ride a glass elevator to see the city. It has a glass floor, and the tower is hit by lightning about 75 times a year. https://socialmedia.xdme.com/tony/videos-book25/page-012.mp4 https://www.youtube.com/embed/tpHLrTGbeyM 128 2026-10-09T14:43:38+00:00 yes https://xdme.com/watch-book25-q013.html https://xdme.com/book25-thumbs/page-013.jpg How do window washers reach the 60th floor? Window washers ride on platforms that hang from cables attached to a rig on the roof. They wear safety harnesses connected to strong anchor points. Some buildings have tracks and machines that move up and down the glass. Washers clean with soapy water and squeegees. They do not work when it is windy or stormy, because safety comes first. https://socialmedia.xdme.com/tony/videos-book25/page-013.mp4 https://www.youtube.com/embed/uXlzlBym6eA 112 2026-10-09T14:43:39+00:00 yes https://xdme.com/watch-book25-q014.html https://xdme.com/book25-thumbs/page-014.jpg What makes a skyscraper green? A green skyscraper is designed to use less energy and water. It might have special windows that block heat, sensors that turn off lights when no one is in a room, and sunshades. Some collect rainwater to flush toilets and water plants. Rooftop solar panels and gardens help, too. These ideas save money and are kinder to the environment. https://socialmedia.xdme.com/tony/videos-book25/page-014.mp4 https://www.youtube.com/embed/GDMfjD1eCWI 109 2026-10-09T14:43:40+00:00 yes https://xdme.com/watch-book25-q015.html https://xdme.com/book25-thumbs/page-015.jpg What gear keeps skyscraper builders safe up high? Workers wear hard hats, bright vests, strong boots, and safety harnesses clipped to secure points. Edges have railings and nets, and tools are tied so they cannot drop. Cranes use signals and radios so everyone knows what is happening. Work stops in high winds or lightning. Careful planning and training mean that safety comes first on a building site. https://socialmedia.xdme.com/tony/videos-book25/page-015.mp4 https://www.youtube.com/embed/GeaEqJCfrY8 109 2026-10-09T14:43:42+00:00 yes https://xdme.com/watch-book25-q016.html https://xdme.com/book25-thumbs/page-016.jpg What is on the roof of a skyscraper? A skyscraper roof is crowded with equipment. There are machines for elevators, big fans and cooling units for air conditioning, antennas for radio and phones, and sometimes water tanks. There may be a rig for window washers, lightning rods, and red lights to warn airplanes. Some roofs have gardens, solar panels, or a helicopter landing area. https://socialmedia.xdme.com/tony/videos-book25/page-016.mp4 https://www.youtube.com/embed/UfXsupngcMI 109 2026-10-09T14:43:43+00:00 yes https://xdme.com/watch-book25-q017.html https://xdme.com/book25-thumbs/page-017.jpg What do architects and engineers each do? An architect designs how a building looks and works, such as where rooms, windows, and doors go. Structural engineers figure out how strong the beams and columns must be to hold everything up. Other engineers plan the heating, cooling, electricity, and water. Builders put the plan into action. Together, they make a building that is useful, beautiful, and safe. https://socialmedia.xdme.com/tony/videos-book25/page-017.mp4 https://www.youtube.com/embed/nUucLJuhUVg 109 2026-10-09T14:43:44+00:00 yes https://xdme.com/watch-book25-q018.html https://xdme.com/book25-thumbs/page-018.jpg Why is it so windy at the foot of a tall building? When wind hits a tall wall, it cannot go through, so some goes up and some is pushed down toward the street. The air also speeds up as it squeezes around corners and between buildings. This can make strong gusts in plazas. Architects test models in wind tunnels, and add trees, canopies, and curved shapes to calm the wind. https://socialmedia.xdme.com/tony/videos-book25/page-018.mp4 https://www.youtube.com/embed/TE83wcGNTmA 106 2026-10-09T14:43:45+00:00 yes https://xdme.com/watch-book25-q019.html https://xdme.com/book25-thumbs/page-019.jpg Why are some skyscrapers rounded, tapered, or twisted? Wind swirling around a tall building can make it wiggle. A shape that changes with height, like a tapering tower or one with a twist, confuses the swirls so that they don't line up and push in rhythm. Rounded corners also make wind flow more smoothly. The Burj Khalifa has a stepped, Y-shaped design for this reason, and it is also pretty to look at. https://socialmedia.xdme.com/tony/videos-book25/page-019.mp4 https://www.youtube.com/embed/fbwn-nOx8ZY 114 2026-10-09T14:43:46+00:00 yes https://xdme.com/watch-book25-q020.html https://xdme.com/book25-thumbs/page-020.jpg Can a skyscraper be made of wood? Yes. Engineers glue layers of wood together crosswise to make mass timber, such as cross-laminated timber, which is strong and fire-resistant because the outer layer chars and protects the inside. Mass timber stores carbon and can be built quickly. A student residence at the University of British Columbia, finished in 2017, is 18 stories tall and built with wood. https://socialmedia.xdme.com/tony/videos-book25/page-020.mp4 https://www.youtube.com/embed/C2ad3hkSdcI 114 2026-10-09T14:43:47+00:00 yes https://xdme.com/watch-book25-q021.html https://xdme.com/book25-thumbs/page-021.jpg How are old buildings taken down safely? When a building is no longer needed, crews plan carefully. They remove materials that could be harmful, then take the building apart piece by piece from the top using machines or by hand. Most of the concrete, steel, glass, and wood can be sorted and recycled. Experts set up fences and sprays to keep dust and noise low. It is the building process played backward. https://socialmedia.xdme.com/tony/videos-book25/page-021.mp4 https://www.youtube.com/embed/YIeoEDoVlf0 109 2026-10-09T14:43:49+00:00 yes https://xdme.com/watch-book25-q022.html https://xdme.com/book25-thumbs/page-022.jpg How do builders make sure a tall building is straight? Builders check every column with tools. An old method uses a plumb bob, which is a weight on a string that hangs straight down because of gravity. Today they use laser levels and surveying instruments that measure to a fraction of an inch, and GPS to check the whole tower. A building may lean very slightly in wind, but it swings back. https://socialmedia.xdme.com/tony/videos-book25/page-022.mp4 https://www.youtube.com/embed/yaw0jpuviOg 108 2026-10-09T14:43:50+00:00 yes https://xdme.com/watch-book25-q023.html https://xdme.com/book25-thumbs/page-023.jpg How do engineers know how much weight a floor can hold? Engineers calculate the weight of the building itself, plus people, furniture, and equipment, and then multiply it by a safety factor so the floor is much stronger than it needs to be. Signs in libraries and storage rooms tell you the maximum weight. Floors are made of strong concrete and steel. Testing in labs checks the numbers. https://socialmedia.xdme.com/tony/videos-book25/page-023.mp4 https://www.youtube.com/embed/EuQMKfdPqKw 110 2026-10-09T14:43:51+00:00 yes https://xdme.com/watch-book25-q024.html https://xdme.com/book25-thumbs/page-024.jpg How do big buildings stay warm in winter and cool in summer? Big buildings have heating and cooling systems with boilers, chillers, ducts, and fans. Air is heated or cooled in machines and sent through ducts to every room. Sensors and thermostats adjust the temperature in different zones. Filters clean the air. Smart controls and good insulation save energy. Some systems recover heat from the air leaving the building. https://socialmedia.xdme.com/tony/videos-book25/page-024.mp4 https://www.youtube.com/embed/ZMRWfuBKLUM 107 2026-10-09T14:43:52+00:00 yes https://xdme.com/watch-book25-q025.html https://xdme.com/book25-thumbs/page-025.jpg How do computers help design a building before it is built? Architects and engineers use computers to make a 3D model of a building, showing every beam, pipe, and wire. They can test how sunlight falls, how wind moves, and how people would walk through it. The software finds mistakes, like pipes that would bump into beams, before anything is built. Some teams even take virtual reality tours. https://socialmedia.xdme.com/tony/videos-book25/page-025.mp4 https://www.youtube.com/embed/tlsmfjksoeM 113 2026-10-09T14:43:54+00:00 yes https://xdme.com/watch-book25-q026.html https://xdme.com/book25-thumbs/page-026.jpg How do traffic lights know when cars are waiting? Many intersections have a loop of wire buried in the pavement. A small electric current runs through it, and when a car sits on top, the metal changes the loop’s magnetic field, which tells the light’s computer that a vehicle is waiting. Other lights use cameras or radar. This lets the signal change when needed instead of using a fixed timer. Engineers also time lights along a street so cars at the speed limit meet green after green. https://socialmedia.xdme.com/tony/videos-book25/page-026.mp4 https://www.youtube.com/embed/AUwXARXXV7k 120 2026-10-09T14:43:54+00:00 yes https://xdme.com/watch-book25-q027.html https://xdme.com/book25-thumbs/page-027.jpg Why do crossing guards hold up a big STOP sign? Crossing guards help children and other walkers cross busy streets near schools. A guard steps into the road only when it is safe and holds up a big STOP sign so drivers can see the signal from far away. Drivers must stay stopped until the guard and everyone crossing have left the road. Guards wear bright vests so they can be seen in any weather. https://socialmedia.xdme.com/tony/videos-book25/page-027.mp4 https://www.youtube.com/embed/qZE5gemLNFc 111 2026-10-09T14:43:56+00:00 yes https://xdme.com/watch-book25-q028.html https://xdme.com/book25-thumbs/page-028.jpg Why are stop signs red octagons? A stop sign needs to be spotted fast, even from far away or from behind. No other sign has eight sides, so the octagon shape is unique, and the red color means stop or danger. Because of its shape, you can recognize it even when snow covers its face. Different shapes mean different things: triangles warn about yielding, diamonds warn of hazards, and rectangles give information. https://socialmedia.xdme.com/tony/videos-book25/page-028.mp4 https://www.youtube.com/embed/50ydjaG8uWA 111 2026-10-09T14:43:57+00:00 yes https://xdme.com/watch-book25-q029.html https://xdme.com/book25-thumbs/page-029.jpg How do road builders make a road layer by layer? A road starts with leveled, packed soil. On top go layers of crushed stone that spread out the weight of traffic and let water drain away. Finally, workers lay hot asphalt or pour concrete on the top. The road is slightly higher in the middle, so rain runs off to the sides. Big machines like graders, pavers, and rollers do the work. https://socialmedia.xdme.com/tony/videos-book25/page-029.mp4 https://www.youtube.com/embed/_4rkvqH7e7o 104 2026-10-09T14:43:58+00:00 yes https://xdme.com/watch-book25-q030.html https://xdme.com/book25-thumbs/page-030.jpg Why are some roads black and some light gray? Black roads are made from asphalt, which is a sticky black material from oil mixed with stones. It is quick to lay, bendy, and quiet to drive on. Light gray roads are made of concrete, a mix of cement, sand, and gravel. Concrete is hard and long-lasting but can crack and thump at joints. Each is chosen to fit the job, climate, and cost. https://socialmedia.xdme.com/tony/videos-book25/page-030.mp4 https://www.youtube.com/embed/2o-F1BI0gwc 110 2026-10-09T14:43:59+00:00 yes https://xdme.com/watch-book25-q031.html https://xdme.com/book25-thumbs/page-031.jpg How do potholes form each winter and spring? Water seeps into small cracks in the road. When it freezes at night, it turns to ice and expands, making the crack bigger. When the ice melts, a gap is left under the pavement. Then cars and trucks drive over the weak spot and break off pieces. After several freezes and thaws, a hole appears. Crews fill potholes with fresh asphalt. https://socialmedia.xdme.com/tony/videos-book25/page-031.mp4 https://www.youtube.com/embed/8oB0sNLjPmU 110 2026-10-09T14:44:00+00:00 yes https://xdme.com/watch-book25-q032.html https://xdme.com/book25-thumbs/page-032.jpg Why do roads have painted lines, and what do solid and dashed lines mean? Painted lines tell drivers where each lane is and which way traffic goes. In Canada and the United States, yellow lines separate traffic going in opposite directions, and white lines separate lanes going the same way. A dashed line means drivers may pass or change lanes when it is safe, and a solid line means stay in your lane. Crews repaint lines often because tires and snowplows wear them away. https://socialmedia.xdme.com/tony/videos-book25/page-032.mp4 https://www.youtube.com/embed/jpXZVT7xAcQ 119 2026-10-09T14:44:01+00:00 yes https://xdme.com/watch-book25-q033.html https://xdme.com/book25-thumbs/page-033.jpg How do speed bumps make cars slow down? A speed bump makes a car's wheels go up and over a little hill. If the car goes fast, the bump jolts the car and everyone inside, so drivers slow down to stay comfortable. Going slowly means a smooth ride. Slower speeds give drivers more time to notice children, pets, and people crossing. They are used near schools and parks. https://socialmedia.xdme.com/tony/videos-book25/page-033.mp4 https://www.youtube.com/embed/hYQVOTJT914 107 2026-10-09T14:44:02+00:00 yes https://xdme.com/watch-book25-q034.html https://xdme.com/book25-thumbs/page-034.jpg Why do roundabouts help traffic flow? In a roundabout, cars go around a circle in one direction and yield to traffic already in it. Because all vehicles enter at a gentle angle and slow down, the crashes that do happen tend to be less serious than at crossings. Traffic keeps moving without waiting for red lights, which also saves fuel. Roundabouts need space, so they don't fit everywhere. https://socialmedia.xdme.com/tony/videos-book25/page-034.mp4 https://www.youtube.com/embed/_7IjESoKbj0 109 2026-10-09T14:44:04+00:00 yes https://xdme.com/watch-book25-q035.html https://xdme.com/book25-thumbs/page-035.jpg Why do traffic jams sometimes happen even without an accident? A jam can start when one driver taps the brakes. The next driver brakes a little harder, and the next even harder. The slowdown moves backward along the road as a wave, even after the first driver has sped up again. Scientists have seen this wave in experiments with cars on a circular track. Leaving space and driving smoothly can help. https://socialmedia.xdme.com/tony/videos-book25/page-035.mp4 https://www.youtube.com/embed/PXF7nepK75U 109 2026-10-09T14:44:05+00:00 yes https://xdme.com/watch-book25-q036.html https://xdme.com/book25-thumbs/page-036.jpg How does a phone know how slow the traffic is? A phone uses signals from satellites to find where it is. When many phones in cars are moving slowly on the same road, the map app can see that the road is crowded and color it red. It uses this to suggest faster routes. The information is combined, and the app can learn the usual patterns of busy times. https://socialmedia.xdme.com/tony/videos-book25/page-036.mp4 https://www.youtube.com/embed/lVPfqECpFzQ 107 2026-10-09T14:44:07+00:00 yes https://xdme.com/watch-book25-q037.html https://xdme.com/book25-thumbs/page-037.jpg Why do some cities have lanes just for buses? A bus carries many more people than a car, so it makes sense to keep it moving. A bus-only lane lets buses skip past traffic jams, so trips are faster and more reliable. More people choose the bus, which means fewer cars on the road. A single bus can take the place of dozens of cars. https://socialmedia.xdme.com/tony/videos-book25/page-037.mp4 https://www.youtube.com/embed/ujYNwjsB-Hs 108 2026-10-09T14:44:08+00:00 yes https://xdme.com/watch-book25-q038.html https://xdme.com/book25-thumbs/page-038.jpg Why do some city vehicles hang on wires above the street? Streetcars and trolley buses run on electricity from overhead wires. A pole or a frame on the roof, called a pantograph, touches the wire and brings electric current down to the motor. For streetcars, the current returns through the rails. Toronto has one of the largest streetcar systems in North America. The wires keep the vehicle from needing a big battery or engine. Stay far away from overhead wires. https://socialmedia.xdme.com/tony/videos-book25/page-038.mp4 https://www.youtube.com/embed/uThh4MKNPVI 117 2026-10-09T14:44:11+00:00 yes https://xdme.com/watch-book25-q039.html https://xdme.com/book25-thumbs/page-039.jpg Why do you feel wind in a subway station before the train comes? A train moving in a tunnel pushes a column of air ahead of it, like a piston in a bicycle pump. The air has nowhere to go but through the tunnel and out into the station, so you feel a breeze or gust before the train arrives. When the train leaves, it pulls air along after it. Stand back from the platform edge. https://socialmedia.xdme.com/tony/videos-book25/page-039.mp4 https://www.youtube.com/embed/Y7sYaFHmR0U 103 2026-10-09T14:44:12+00:00 yes https://xdme.com/watch-book25-q040.html https://xdme.com/book25-thumbs/page-040.jpg How does an escalator work? An escalator is a long staircase on a loop. Its steps are linked to a pair of chains, driven around by a motor. At the top and bottom, the steps flatten out, so you step on and off easily. The handrail moves at the same speed. Stand in the middle, hold on, keep your shoes tied, and keep your hands and clothing away from the sides. https://socialmedia.xdme.com/tony/videos-book25/page-040.mp4 https://www.youtube.com/embed/sFqP3GMHMCA 107 2026-10-09T14:44:14+00:00 yes https://xdme.com/watch-book25-q041.html https://xdme.com/book25-thumbs/page-041.jpg Why do bike lanes keep cyclists safer? A bike lane gives cyclists their own space away from fast-moving cars. Painted lanes help, and protected lanes with barriers or curbs help even more. When drivers and cyclists know where to be, there are fewer surprises. Bike riders should wear helmets, use lights at night, and use hand signals. More bike lanes also mean more people can choose to ride. https://socialmedia.xdme.com/tony/videos-book25/page-041.mp4 https://www.youtube.com/embed/EhMzyvYy-o0 106 2026-10-09T14:44:15+00:00 yes https://xdme.com/watch-book25-q042.html https://xdme.com/book25-thumbs/page-042.jpg How do ambulances and fire trucks get through busy traffic? Emergency vehicles use loud sirens and flashing lights to tell drivers to make way. When you hear a siren, pull to the right and stop if you can safely do so. Some cities have special systems that turn traffic lights green for approaching emergency vehicles. Trained drivers practice navigating through traffic safely. Making space can help someone who needs help fast. https://socialmedia.xdme.com/tony/videos-book25/page-042.mp4 https://www.youtube.com/embed/PUjrsKIaxyM 111 2026-10-09T14:44:16+00:00 yes https://xdme.com/watch-book25-q043.html https://xdme.com/book25-thumbs/page-043.jpg Why does crossing at the corner and looking both ways work? A moving car needs time and distance to stop. It first travels while the driver reacts, and then keeps rolling while the brakes work. If a car goes twice as fast, it takes about four times as far to stop. That's why cars cannot stop suddenly. Use crosswalks, stop at the curb, look and listen, and wait until drivers see you. https://socialmedia.xdme.com/tony/videos-book25/page-043.mp4 https://www.youtube.com/embed/-Z8rMchJTPw 107 2026-10-09T14:44:17+00:00 yes https://xdme.com/watch-book25-q044.html https://xdme.com/book25-thumbs/page-044.jpg Why do different countries drive on different sides of the road? Long ago, travelers on horseback and in wagons chose sides for their own reasons. Over time, countries made rules to keep everyone safe. Canada, the United States, and many other countries drive on the right. About a third of people live in countries that drive on the left, such as the United Kingdom and Japan. Cars are built to fit the rule. https://socialmedia.xdme.com/tony/videos-book25/page-044.mp4 https://www.youtube.com/embed/12jHscy0sUc 111 2026-10-09T14:44:18+00:00 yes https://xdme.com/watch-book25-q045.html https://xdme.com/book25-thumbs/page-045.jpg How do street names and house numbers help people find places? Streets with names or numbers, and houses with numbers, make a map you can read. Often, numbers go up as you move farther along the street, and odd numbers are on one side with even numbers on the other. This pattern helps delivery drivers, visitors, and emergency crews find the right door quickly. A clear number on your house can save time. https://socialmedia.xdme.com/tony/videos-book25/page-045.mp4 https://www.youtube.com/embed/3wbeSw4KUOs 110 2026-10-09T14:44:20+00:00 yes https://xdme.com/watch-book25-q046.html https://xdme.com/book25-thumbs/page-046.jpg Why do some cities have ferries? Where water cuts a city in two, a ferry can carry people and cars across without needing an expensive bridge or tunnel. Boats float because they push away water equal to their weight, so even big ferries stay up. Toronto's ferries take people to the Toronto Islands. Ferries are important in places like Vancouver and Halifax, too. https://socialmedia.xdme.com/tony/videos-book25/page-046.mp4 https://www.youtube.com/embed/FncQYbKU43A 94 2026-10-09T14:44:21+00:00 yes https://xdme.com/watch-book25-q047.html https://xdme.com/book25-thumbs/page-047.jpg How do parking garages stack so many cars? A parking garage stacks many levels of flat floors, connected by ramps, so many cars can fit in a small footprint. Ramps may spiral or run back and forth. Sensors above each space can detect whether a car is there and light up green or red, guiding drivers to open spots. Walls and ceilings are strong concrete. Take care to stay near the adults in garages. https://socialmedia.xdme.com/tony/videos-book25/page-047.mp4 https://www.youtube.com/embed/44X85t_tUfg 108 2026-10-09T14:44:23+00:00 yes https://xdme.com/watch-book25-q048.html https://xdme.com/book25-thumbs/page-048.jpg Why are more city buses powered by electricity? An electric bus runs on a big battery and a quiet motor. It has no tailpipe, so it makes cleaner air on busy streets. It can also use its brakes to put some energy back into the battery. Buses are charged at night or at stops using special plugs. Because city buses stop and start a lot, electric motors work well for them. https://socialmedia.xdme.com/tony/videos-book25/page-048.mp4 https://www.youtube.com/embed/21gQF2fLMcE 108 2026-10-09T14:44:24+00:00 yes https://xdme.com/watch-book25-q049.html https://xdme.com/book25-thumbs/page-049.jpg How do traffic engineers count cars? Engineers use rubber tubes laid across the road that sense each axle as a wheel rolls over it. Cameras and computers can recognize vehicles, and loops in the pavement sense cars passing. The counts show where roads are busy at different times and help plan traffic lights and new lanes. You can count too: sit safely on a sidewalk with a grown-up and make tally marks. https://socialmedia.xdme.com/tony/videos-book25/page-049.mp4 https://www.youtube.com/embed/Jj9haRdC1fk 105 2026-10-09T14:44:25+00:00 yes https://xdme.com/watch-book25-q050.html https://xdme.com/book25-thumbs/page-050.jpg Why do highway ramps curve in big loops? Highways go fast, so ramps and curves need to be gentle. A loop ramp lets a driver turn off or onto a highway without crossing other lanes or stopping. Shapes called cloverleaf and diamond interchanges let cars change roads on different levels. The curve is tilted a little, or banked, so cars stay on the road. Engineers plan them carefully for safety and flow. https://socialmedia.xdme.com/tony/videos-book25/page-050.mp4 https://www.youtube.com/embed/OYXy3hzV0hM 112 2026-10-09T14:44:26+00:00 yes https://xdme.com/watch-book25-q051.html https://xdme.com/book25-thumbs/page-051.jpg How does water travel through a city's pipes to your tap? Treated water leaves the treatment plant through huge pipes called water mains buried under the streets. They branch into smaller pipes that run along every block, and a thin service pipe connects each building. Pumps and tall tanks keep the water under pressure so that it flows when you turn on a faucet. Valves let crews shut off sections for repairs. https://socialmedia.xdme.com/tony/videos-book25/page-051.mp4 https://www.youtube.com/embed/Jdg24Tye9Mw 107 2026-10-09T14:44:27+00:00 yes https://xdme.com/watch-book25-q052.html https://xdme.com/book25-thumbs/page-052.jpg Why do water mains sometimes break? Water pipes can last a very long time, but not forever. They can rust, get old, or be pushed by moving soil. Very cold weather can make the ground freeze and shift, putting stress on pipes. When a main breaks, water bubbles out of the ground and may flood a street. Crews shut off nearby valves, dig down, and repair the pipe. https://socialmedia.xdme.com/tony/videos-book25/page-052.mp4 https://www.youtube.com/embed/Q50Xxa9Egm4 103 2026-10-09T14:44:28+00:00 yes https://xdme.com/watch-book25-q053.html https://xdme.com/book25-thumbs/page-053.jpg How do fire hydrants work? A fire hydrant is a handy tap connected to the city's water main. Firefighters attach a hose with a special wrench and open a valve, and strong water pressure from the pipe sends water through. Hydrants have caps on their outlets, and the colored tops can tell firefighters how much water flows. Never open a hydrant yourself, and keep snow cleared away so that it is easy to find. https://socialmedia.xdme.com/tony/videos-book25/page-053.mp4 https://www.youtube.com/embed/sncu15byTzw 110 2026-10-09T14:44:29+00:00 yes https://xdme.com/watch-book25-q054.html https://xdme.com/book25-thumbs/page-054.jpg Why are manhole covers round? A round cover cannot fall through its own hole, no matter how you turn it, because a circle has the same width in every direction. A square one could slip through diagonally. Manhole covers are heavy iron, sometimes 100 pounds or more, so they stay put under traffic. Workers use special hooks to lift them. Never try to open one. https://socialmedia.xdme.com/tony/videos-book25/page-054.mp4 https://www.youtube.com/embed/ZSmxgYe8tvg 111 2026-10-09T14:44:30+00:00 yes https://xdme.com/watch-book25-q055.html https://xdme.com/book25-thumbs/page-055.jpg Why does steam sometimes rise from street grates? In some cities, underground steam pipes carry heat to buildings, and steam can escape through cracks and openings. Warm underground air meeting cold winter air can also form clouds, just like your breath on a cold day. The steam looks spooky, but it is only water vapor. Crews keep an eye on it, and people should stay away from hot grates. https://socialmedia.xdme.com/tony/videos-book25/page-055.mp4 https://www.youtube.com/embed/O3szDVEUNkw 107 2026-10-09T14:44:31+00:00 yes https://xdme.com/watch-book25-q056.html https://xdme.com/book25-thumbs/page-056.jpg How do city workers look inside a sewer pipe? Sewer pipes are underground, so crews send in small robots that roll through the pipes on wheels or tracks. A camera and bright light on the robot send live video to a screen above ground. Workers watch for cracks, tree roots, and clogs, and then decide what to repair. People go into sewers only with special training, air monitors, and safety gear, and nobody should ever open a manhole cover. https://socialmedia.xdme.com/tony/videos-book25/page-056.mp4 https://www.youtube.com/embed/3OOxp85MON8 109 2026-10-09T14:44:32+00:00 yes https://xdme.com/watch-book25-q057.html https://xdme.com/book25-thumbs/page-057.jpg What happens at a wastewater treatment plant? Water from sinks, showers, and toilets flows through sewers to a treatment plant. First, screens catch large objects. Then the water sits in tanks, where solids sink. Tiny microbes eat the leftover waste while air is bubbled through. Finally, the water is disinfected, often with ultraviolet light or chlorine, before it is released to a river or lake, much cleaner than when it arrived. https://socialmedia.xdme.com/tony/videos-book25/page-057.mp4 https://www.youtube.com/embed/d6DuXA11tig 111 2026-10-09T14:44:33+00:00 yes https://xdme.com/watch-book25-q058.html https://xdme.com/book25-thumbs/page-058.jpg Why do some sewers overflow when it rains hard? In some older parts of cities, one pipe carries both rainwater and household wastewater. When a storm brings lots of rain, the pipe can fill up faster than the treatment plant can handle. Extra water may overflow into a river or lake. Cities are building big storage tanks and tunnels, separating pipes, and adding rain gardens and green roofs to soak up rain. https://socialmedia.xdme.com/tony/videos-book25/page-058.mp4 https://www.youtube.com/embed/AGXjHsc6Q7g 108 2026-10-09T14:44:34+00:00 yes https://xdme.com/watch-book25-q059.html https://xdme.com/book25-thumbs/page-059.jpg Why are some city wires buried while others hang on poles? Wires on poles are cheaper to build and easy to fix, but they are exposed to wind, ice, and falling branches. Buried wires are protected from storms and don't clutter the view. However, digging costs a lot, and it can take longer to find and repair a problem. Cities use both, depending on the place. https://socialmedia.xdme.com/tony/videos-book25/page-059.mp4 https://www.youtube.com/embed/PhY6orsQG0Q 106 2026-10-09T14:44:35+00:00 yes https://xdme.com/watch-book25-q060.html https://xdme.com/book25-thumbs/page-060.jpg What are the big green boxes at street corners? These boxes hold equipment for the city's electric, phone, internet, or traffic-signal systems. They protect electronics from rain and snow and keep people safe from live wires. Some contain computers that control the traffic lights. Never climb on, open, or touch them. In many places, artists paint colorful pictures on them to brighten up the neighborhood. https://socialmedia.xdme.com/tony/videos-book25/page-060.mp4 https://www.youtube.com/embed/aNsThjDIKCk 110 2026-10-09T14:44:37+00:00 yes https://xdme.com/watch-book25-q061.html https://xdme.com/book25-thumbs/page-061.jpg How does a cell tower pass your phone call along? A cell phone is a small radio. When you make a call, it sends signals to the nearest cell tower, which has antennas that talk to many phones at once. The tower passes your call along through cables, often fiber, to the next place it needs to go. As you travel, your call hands off from tower to tower. Cities need many towers because each one covers only a small area. https://socialmedia.xdme.com/tony/videos-book25/page-061.mp4 https://www.youtube.com/embed/oAyfHKLUk-g 111 2026-10-09T14:44:38+00:00 yes https://xdme.com/watch-book25-q062.html https://xdme.com/book25-thumbs/page-062.jpg Why is a strong smell added to the gas that heats our homes? Natural gas has no smell at all, and it can be dangerous if it leaks. So companies add a harmless chemical with a strong odor, often described as rotten eggs, so that people notice a leak right away. If you ever smell it at home, tell a grown-up and go outside. Do not turn lights on or off, and call for help from outside. https://socialmedia.xdme.com/tony/videos-book25/page-062.mp4 https://www.youtube.com/embed/kB_qBhYg9B0 106 2026-10-09T14:44:39+00:00 yes https://xdme.com/watch-book25-q063.html https://xdme.com/book25-thumbs/page-063.jpg Why do towns have water towers? A water tower is a big tank on tall legs that holds water high above the town. The height makes pressure, because the weight of the water pushes it down through the pipes. It works without extra pumps. The tank also stores water for busy times, such as mornings and evenings. Pumps fill it at night when demand is low. https://socialmedia.xdme.com/tony/videos-book25/page-063.mp4 https://www.youtube.com/embed/HMzNmDGh654 106 2026-10-09T14:44:41+00:00 yes https://xdme.com/watch-book25-q064.html https://xdme.com/book25-thumbs/page-064.jpg How does a skyscraper push tap water up hundreds of feet? The city's pressure alone can only push water up a few stories. In tall buildings, powerful pumps in the basement push water up to the higher floors. Some buildings pump water to tanks on the roof and let gravity feed the floors below. Buildings are divided into zones so that the pressure is never too high at the bottom. https://socialmedia.xdme.com/tony/videos-book25/page-064.mp4 https://www.youtube.com/embed/GLXoCw9i58k 104 2026-10-09T14:44:42+00:00 yes https://xdme.com/watch-book25-q065.html https://xdme.com/book25-thumbs/page-065.jpg How does cold water from Lake Ontario cool Toronto's downtown buildings? Pipes reach about three miles out into the lake and draw up very cold water from deep down, near 39 degrees Fahrenheit. In downtown buildings, this cold water passes through heat exchangers that cool the air-conditioning system's own water, then goes on to the city's drinking water supply. The two waters do not mix. It saves a great deal of electricity. https://socialmedia.xdme.com/tony/videos-book25/page-065.mp4 https://www.youtube.com/embed/NJacvvvUbEw 115 2026-10-09T14:44:43+00:00 yes https://xdme.com/watch-book25-q066.html https://xdme.com/book25-thumbs/page-066.jpg How does a 911 call get help to the right place? When you dial 911 in Canada, your call goes to an emergency call center. A trained dispatcher answers, asks what is wrong and where you are, and sends police, firefighters, or an ambulance. Phones often help share your location. Stay calm, speak clearly, and know your address. Only call 911 for real emergencies. https://socialmedia.xdme.com/tony/videos-book25/page-066.mp4 https://www.youtube.com/embed/TuIpOL63eHs 110 2026-10-09T14:44:44+00:00 yes https://xdme.com/watch-book25-q067.html https://xdme.com/book25-thumbs/page-067.jpg How do hospitals keep running during a power outage? Hospitals have backup generators that start within seconds when the power fails, using fuel stored on site. Some equipment also uses batteries, called uninterruptible power supplies, to bridge the gap. Backup power keeps lights, machines, and heating running so patients stay safe. Other important places, such as water plants and phone systems, have backup power too. https://socialmedia.xdme.com/tony/videos-book25/page-067.mp4 https://www.youtube.com/embed/uqzHGnShat4 109 2026-10-09T14:44:46+00:00 yes https://xdme.com/watch-book25-q068.html https://xdme.com/book25-thumbs/page-068.jpg What is under a city street? Under a city street lie many hidden layers. Large sewer pipes are often deepest, with water mains above them. Electric cables, telephone and fiber lines, and gas pipes lie nearer the surface. In some cities, subway tunnels and steam pipes share the space. Each system has its own depth and location. Maps and markings tell workers what is where. https://socialmedia.xdme.com/tony/videos-book25/page-068.mp4 https://www.youtube.com/embed/uN5qdaM-ctI 106 2026-10-09T14:44:47+00:00 yes https://xdme.com/watch-book25-q069.html https://xdme.com/book25-thumbs/page-069.jpg How do crews fix pipes without digging up the whole street? Instead of digging a long trench, crews can dig small holes at each end of a pipe. They can then pull a flexible liner through the old pipe and harden it into a new pipe inside, like a sleeve. Another way is horizontal drilling, which pushes a new pipe underground through a drilled path. These tricks save time and keep roads open. https://socialmedia.xdme.com/tony/videos-book25/page-069.mp4 https://www.youtube.com/embed/ZB9LGfgmuC8 103 2026-10-09T14:44:48+00:00 yes https://xdme.com/watch-book25-q070.html https://xdme.com/book25-thumbs/page-070.jpg Why are old city pipes replaced with new materials? Old pipes, made of cast iron, clay, or lead, can rust, crack, or leak after many decades. New pipes made of plastic, ductile iron, or concrete resist rust and last longer. Replacing old pipes keeps water clean and prevents leaks and breaks. Cities do it a few streets at a time because it is big, careful work. https://socialmedia.xdme.com/tony/videos-book25/page-070.mp4 https://www.youtube.com/embed/mmul1HuyGoY 109 2026-10-09T14:44:49+00:00 yes https://xdme.com/watch-book25-q071.html https://xdme.com/book25-thumbs/page-071.jpg How does a water meter count how much water you use? A water meter sits on the pipe entering a building. Moving water spins a small disc or wheel inside it, and each turn means a certain amount of water has passed. Gears turn the numbers on a dial. Newer meters use sound waves or send data by radio. The water company uses the numbers to calculate the water bill. https://socialmedia.xdme.com/tony/videos-book25/page-071.mp4 https://www.youtube.com/embed/0sf-MZGzwno 104 2026-10-09T14:44:49+00:00 yes https://xdme.com/watch-book25-q072.html https://xdme.com/book25-thumbs/page-072.jpg What are the big orange balls on some power lines? Those balls are markers that make power lines easier to see for low-flying airplanes and helicopters. They are bright orange or white so pilots can spot the wires from far away. Some lines also have spirals or flappers that help birds see them. These simple devices help keep both pilots and birds safe. Stay far away from power lines, and never fly a kite or climb a tree near them. https://socialmedia.xdme.com/tony/videos-book25/page-072.mp4 https://www.youtube.com/embed/R9ExWRCqySg 110 2026-10-09T14:51:22+00:00 yes https://xdme.com/watch-book25-q073.html https://xdme.com/book25-thumbs/page-073.jpg Why do wires sag between poles? Wires hang in a gentle curve because of their own weight, and they are installed with some slack on purpose. In hot weather, metal expands and the wires sag more. In cold weather, the metal shrinks and they pull tighter. Ice and wind can add weight and tug. Designers leave enough slack so that wires won't snap in winter. https://socialmedia.xdme.com/tony/videos-book25/page-073.mp4 https://www.youtube.com/embed/lriRVjt1SbY 100 2026-10-09T14:51:23+00:00 yes https://xdme.com/watch-book25-q074.html https://xdme.com/book25-thumbs/page-074.jpg Why don't drains make your bathroom smell like the sewer? Under each sink is a U-shaped pipe called a trap that always holds a little water. This water plug blocks smelly sewer gas from coming back up. Small vent pipes, often poking through the roof, let air into the drains so that they flow smoothly and the water in the trap does not get sucked out. If a drain is unused for months, the water can dry up. https://socialmedia.xdme.com/tony/videos-book25/page-074.mp4 https://www.youtube.com/embed/aQJU9qVasII 102 2026-10-09T14:51:24+00:00 yes https://xdme.com/watch-book25-q075.html https://xdme.com/book25-thumbs/page-075.jpg How do pumps push water uphill? Many city pumps have a spinning part called an impeller with curved blades. As it whirls, it flings water outward, which creates pressure that pushes water through the pipe. Pumps run on electric motors and are used in water systems, sewers, and buildings. A pump cannot pull water up more than about 34 feet by suction alone, so it is usually placed to push. https://socialmedia.xdme.com/tony/videos-book25/page-075.mp4 https://www.youtube.com/embed/ASHLwu1N69s 110 2026-10-09T14:51:25+00:00 yes https://xdme.com/watch-book25-q076.html https://xdme.com/book25-thumbs/page-076.jpg Why do raccoons do so well in cities? Raccoons are curious and eat almost anything, from fruit to insects to leftovers. Cities give them food in garbage and pet bowls, and places to sleep in trees, sheds, chimneys, and attics. There are few big predators, and winters in the city are often milder. Most raccoons are active at night. Never feed or touch a raccoon, and keep trash bins latched. https://socialmedia.xdme.com/tony/videos-book25/page-076.mp4 https://www.youtube.com/embed/5P8AQHSE0vQ 111 2026-10-09T14:51:26+00:00 yes https://xdme.com/watch-book25-q077.html https://xdme.com/book25-thumbs/page-077.jpg Why do coyotes live in some cities? Coyotes are adaptable animals that eat mice, rabbits, fruit, and sometimes leftovers. City parks, ravines, and golf courses give them places to hide, and there are few big predators to worry them. Most coyotes are shy and stay away from people. If you see one, give it plenty of space, do not feed it, and tell a grown-up. https://socialmedia.xdme.com/tony/videos-book25/page-077.mp4 https://www.youtube.com/embed/ZxCZyd0zh24 106 2026-10-09T14:51:27+00:00 yes https://xdme.com/watch-book25-q078.html https://xdme.com/book25-thumbs/page-078.jpg Why do peregrine falcons nest on skyscrapers? Peregrine falcons naturally nest on high cliff ledges. A skyscraper's ledge looks just like a cliff to them, and the city has lots of pigeons to eat. Many cities, including Toronto, have falcon nest boxes on tall buildings, and people watch them on webcams. These birds were once rare, and seeing them back is good news for nature. https://socialmedia.xdme.com/tony/videos-book25/page-078.mp4 https://www.youtube.com/embed/7ratjnXIb4E 110 2026-10-09T14:51:29+00:00 yes https://xdme.com/watch-book25-q079.html https://xdme.com/book25-thumbs/page-079.jpg Why are there so many pigeons in cities? City pigeons are descended from rock doves, which nest on cliffs. Building ledges are like cliffs, and people drop food crumbs, so pigeons thrive. They have been living with people for thousands of years. Pigeons are smart and can learn to recognize people and landmarks. Feeding them in big groups causes crowding and messes, so it is best to let them find natural food. https://socialmedia.xdme.com/tony/videos-book25/page-079.mp4 https://www.youtube.com/embed/-DIck9F4AKk 104 2026-10-09T14:51:30+00:00 yes https://xdme.com/watch-book25-q080.html https://xdme.com/book25-thumbs/page-080.jpg How do common nighthawks nest on city rooftops? Common nighthawks are birds that catch flying insects at dusk. They used to nest on bare ground in open areas, and flat gravel roofs are similar. A mother lays her camouflaged eggs right on the gravel with no nest. You may hear the booming sound of males diving through the air in summer evenings. Nighthawks are listed as a species at risk in Canada. https://socialmedia.xdme.com/tony/videos-book25/page-080.mp4 https://www.youtube.com/embed/AJJE0ENYzA4 110 2026-10-09T14:51:31+00:00 yes https://xdme.com/watch-book25-q081.html https://xdme.com/book25-thumbs/page-081.jpg Why do city birds sing at a higher pitch? In noisy cities, low rumbles from traffic can drown out deep bird songs. Scientists found that some birds, such as great tits and song sparrows, sing higher or louder in the city so that other birds can hear them. Some even sing at different times of day. Birds adapt to the soundscape around them. https://socialmedia.xdme.com/tony/videos-book25/page-081.mp4 https://www.youtube.com/embed/wcqh4LHO9NM 106 2026-10-09T14:51:32+00:00 yes https://xdme.com/watch-book25-q082.html https://xdme.com/book25-thumbs/page-082.jpg How did crows in Japan learn to use traffic lights to crack nuts? In Sendai, Japan, scientists saw crows using a clever trick. A crow would drop a walnut on the road in front of cars that had stopped at a red light. After the cars drove over it and cracked the shell, the crow waited until the crossing light turned green for walkers. Then it hopped down to eat the nut safely. Crows solve puzzles and use tools. https://socialmedia.xdme.com/tony/videos-book25/page-082.mp4 https://www.youtube.com/embed/sEusvTFL86Q 107 2026-10-09T14:51:34+00:00 yes https://xdme.com/watch-book25-q083.html https://xdme.com/book25-thumbs/page-083.jpg Why do Canada geese stay in city parks all year? Many Canada geese now live in parks and golf courses year-round. Short, soft grass is easy for them to eat, ponds give safety, and few predators bother them. Because food is available, some geese no longer fly south. Geese can be protective of their nests and chicks, so keep a safe distance and do not feed them. https://socialmedia.xdme.com/tony/videos-book25/page-083.mp4 https://www.youtube.com/embed/IbPsm_pPvNc 105 2026-10-09T14:51:36+00:00 yes https://xdme.com/watch-book25-q084.html https://xdme.com/book25-thumbs/page-084.jpg What tiny creatures live on a city sidewalk? A sidewalk may seem empty, but there is a lot of life in its cracks. Ants build nests under paving stones and follow scent trails for food. Tiny springtails, mites, and sow bugs hide in damp corners, and spiders spin webs in sheltered spots. Moss and small weeds grow in cracks. Scientists have found surprising numbers of species in a single block. https://socialmedia.xdme.com/tony/videos-book25/page-084.mp4 https://www.youtube.com/embed/7N8uPv_3HdA 110 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book25-q085.html https://xdme.com/book25-thumbs/page-085.jpg Why do rats live near people, and how can we keep them away? Rats live where there is food, water, and shelter, and people often provide all three by accident. Open trash, spilled food, and clutter give them homes. Rats are very smart and good at climbing and squeezing through small holes. The best way to discourage them is to keep trash sealed, clean up food, and close up gaps in buildings. https://socialmedia.xdme.com/tony/videos-book25/page-085.mp4 https://www.youtube.com/embed/nZmGK57v5p4 104 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book25-q086.html https://xdme.com/book25-thumbs/page-086.jpg What should you do if you meet a wild animal in the city? Stay calm and give the animal plenty of space. Watch from a distance and never try to touch, feed, or chase it. Back away slowly, and keep pets on leashes. Tell a grown-up about the animal. Wild animals can scratch or bite if they are frightened, and feeding them teaches them to depend on people, which is not safe for them. https://socialmedia.xdme.com/tony/videos-book25/page-086.mp4 https://www.youtube.com/embed/B4eXCssuyoU 102 2026-10-09T14:51:38+00:00 yes https://xdme.com/watch-book25-q087.html https://xdme.com/book25-thumbs/page-087.jpg What is a green roof, and how does it help? A green roof is a roof covered with plants. Under the plants are layers of soil, a drainage layer, a root barrier, and a waterproof sheet. The plants soak up rain, so less water rushes into storm drains, and they keep the building cooler in summer and warmer in winter. A green roof also gives bees, butterflies, and birds a place to live. https://socialmedia.xdme.com/tony/videos-book25/page-087.mp4 https://www.youtube.com/embed/9YBng_bJv3s 107 2026-10-09T14:51:39+00:00 yes https://xdme.com/watch-book25-q088.html https://xdme.com/book25-thumbs/page-088.jpg Why do cities plant trees along streets? Street trees give shade, which can make a sidewalk many degrees cooler on a hot day. Leaves catch dust and soak up rain so storm drains do not overflow. Trees give homes to birds and insects, make streets quieter, and are nice to look at. Many people say neighborhoods with trees feel happier. A tree is a helper that never takes a day off. https://socialmedia.xdme.com/tony/videos-book25/page-088.mp4 https://www.youtube.com/embed/p7dXFrsAGJQ 106 2026-10-09T14:51:40+00:00 yes https://xdme.com/watch-book25-q089.html https://xdme.com/book25-thumbs/page-089.jpg How do trees survive in tiny squares of dirt in the sidewalk? City trees have a tough life. They have little room for roots, the soil is often packed hard, and salt from winter roads can harm them. Planners now use special loose soil under the pavement and long planting strips. Mulch and water help. Many cities have crews who water and prune young trees. A tree with room for roots grows better and lives longer. https://socialmedia.xdme.com/tony/videos-book25/page-089.mp4 https://www.youtube.com/embed/XEvXaP73bcE 106 2026-10-09T14:55:17+00:00 yes https://xdme.com/watch-book25-q090.html https://xdme.com/book25-thumbs/page-090.jpg Why do cities plant many different kinds of trees? If a street has only one kind of tree, one pest or disease can wipe out them all. In Ontario, a beetle called the emerald ash borer killed millions of ash trees, leaving some streets bare. Planting a mix of species means some trees will survive any problem. Different trees also give homes to different animals and provide color in different seasons. https://socialmedia.xdme.com/tony/videos-book25/page-090.mp4 https://www.youtube.com/embed/tV0YnWYT_Rw 109 2026-10-09T14:55:18+00:00 yes https://xdme.com/watch-book25-q091.html https://xdme.com/book25-thumbs/page-091.jpg Why do some cities turn empty lots into community gardens? Neighbors can grow vegetables, herbs, and flowers on land that would otherwise sit empty. Fresh food is healthy, and working together builds friendships. Many community gardens use raised beds with clean soil. Kids learn where food comes from, and gardens give bees and butterflies a place to visit. Gardens also soak up rain and make the neighborhood greener. https://socialmedia.xdme.com/tony/videos-book25/page-091.mp4 https://www.youtube.com/embed/MVBNmDgyWJw 111 2026-10-09T14:55:19+00:00 yes https://xdme.com/watch-book25-q092.html https://xdme.com/book25-thumbs/page-092.jpg Why do cities need parks? Parks give people places to play, run, and relax. They also help the environment, because grass and trees soak up rain, cool the air, and give homes to animals. A park can be a place to see birds, watch seasons change, or meet friends. Toronto's High Park has woods, ponds, and a rare oak savanna. Parks are good for body and mind. https://socialmedia.xdme.com/tony/videos-book25/page-092.mp4 https://www.youtube.com/embed/d_TiHXZk2i0 103 2026-10-09T14:55:20+00:00 yes https://xdme.com/watch-book25-q093.html https://xdme.com/book25-thumbs/page-093.jpg Why does Toronto have so many hidden forest valleys? Toronto sits on soft soil left behind by glaciers. Rivers such as the Don and the Humber have carved deep valleys called ravines into this soil over thousands of years. Because the steep slopes were hard to build on, many were left wild and became forests. Today the ravines cover about a sixth of the city and are home to foxes, owls, and wildflowers. https://socialmedia.xdme.com/tony/videos-book25/page-093.mp4 https://www.youtube.com/embed/gplTbIP6NwQ 111 2026-10-09T14:55:24+00:00 yes https://xdme.com/watch-book25-q094.html https://xdme.com/book25-thumbs/page-094.jpg How can plants grow up the side of a building? A living wall or green wall is a wall covered with plants. The plants grow in panels that hold soil or special fabric, and a hidden system of pipes waters them. Plants on walls can cool buildings, soak up noise, and brighten a street. Some are inside, in places like airports and malls. Gardeners must take care of the plants as they would any garden. https://socialmedia.xdme.com/tony/videos-book25/page-094.mp4 https://www.youtube.com/embed/5Cd83lds6Hc 103 2026-10-09T14:55:25+00:00 yes https://xdme.com/watch-book25-q095.html https://xdme.com/book25-thumbs/page-095.jpg Why do some parking lots let rainwater soak through? Regular pavement is waterproof, so rain runs off into drains. Permeable pavement is made with porous material or pavers with gaps in between, so water drains through to a layer of stone and soil below. This reduces puddles, floods, and pollution washed into streams, and it recharges groundwater. It's a way to give rain a place to go. https://socialmedia.xdme.com/tony/videos-book25/page-095.mp4 https://www.youtube.com/embed/znXQgA1UQOU 112 2026-10-09T14:55:25+00:00 yes https://xdme.com/watch-book25-q096.html https://xdme.com/book25-thumbs/page-096.jpg Why can lichens tell scientists about a city's air? Lichens soak up water and air straight through their surfaces, with no roots or thick skin to filter them. That makes them sensitive to pollution. Some lichens disappear where the air has a lot of pollutants, while others can live in dirty air. By counting the kinds of lichens on tree trunks, scientists can judge how healthy the air is. More kinds usually means cleaner air. https://socialmedia.xdme.com/tony/videos-book25/page-096.mp4 https://www.youtube.com/embed/bzaSManTh-4 108 2026-10-09T14:55:26+00:00 yes https://xdme.com/watch-book25-q097.html https://xdme.com/book25-thumbs/page-097.jpg How do animals cross busy roads safely? Roads can block animals from finding food and mates. Wildlife crossings, like bridges covered with plants and tunnels underneath highways, give animals safe paths. In Banff National Park, fences guide elk and deer to crossings, and studies show that collisions with animals dropped by more than 80 percent. In cities, small tunnels help frogs and turtles. https://socialmedia.xdme.com/tony/videos-book25/page-097.mp4 https://www.youtube.com/embed/FQMVf8XUPKg 110 2026-10-09T14:55:27+00:00 yes https://xdme.com/watch-book25-q098.html https://xdme.com/book25-thumbs/page-098.jpg Why are some city lawns turning into wildflower meadows? Mowed grass uses water, fuel, and time, but it does not give much food to wildlife. Wildflower meadows have flowers that feed bees and butterflies, and grasses that give seeds to birds. Their deep roots soak up rain and need less mowing. A meadow can look messy at first, but it is full of life. Some towns set aside strips of land to grow wild. https://socialmedia.xdme.com/tony/videos-book25/page-098.mp4 https://www.youtube.com/embed/BL3XFE_D6lY 103 2026-10-09T14:55:28+00:00 yes https://xdme.com/watch-book25-q099.html https://xdme.com/book25-thumbs/page-099.jpg How can you find the age of a city tree? The best way is to count the rings in a cut stump, since a tree adds one ring each year, but never cut a living tree. For a living tree, you can measure around the trunk at about chest height and divide by about three to estimate its width. Foresters have charts that estimate age from width for each species. Big old trees are precious. https://socialmedia.xdme.com/tony/videos-book25/page-099.mp4 https://www.youtube.com/embed/UKQOa8JAY5I 103 2026-10-09T14:55:29+00:00 yes https://xdme.com/watch-book25-q100.html https://xdme.com/book25-thumbs/page-100.jpg How can you be a city nature detective? Anyone can study nature in a city. Keep a notebook and write down what you see: birds, insects, plants, and animal tracks. Take photos and use an app with a grown-up to share them, so scientists can use your observations. Programs like eBird, iNaturalist, and the Great Backyard Bird Count collect data from many people. Your sightings help real scientists. https://socialmedia.xdme.com/tony/videos-book25/page-100.mp4 https://www.youtube.com/embed/yQTz3qrEwcI 108 2026-10-09T14:55:30+00:00 yes https://xdme.com/watch-book25-q101.html https://xdme.com/book25-thumbs/page-101.jpg How does bright night light change the lives of birds and insects? Many animals use natural light to tell day from night. Migrating birds steer by stars and the Moon, so bright buildings can lure them off course and make them circle until they are tired. Insects swarm around lamps instead of feeding or finding mates. Fireflies can't see each other's flashes. Turning off extra lights helps wildlife find its way again. https://socialmedia.xdme.com/tony/videos-book25/page-101.mp4 https://www.youtube.com/embed/kpULf22cOn4 116 2026-10-09T14:55:31+00:00 yes https://xdme.com/watch-book25-q102.html https://xdme.com/book25-thumbs/page-102.jpg What are "lights out" programs for migrating birds? During spring and fall, billions of birds migrate at night. Bright lit-up towers can confuse them and cause them to collide with glass. In Toronto, a group called FLAP asks building owners to switch off unneeded lights from midnight until dawn during migration. Birds find their way better, and the buildings save energy too. Many cities have joined. https://socialmedia.xdme.com/tony/videos-book25/page-102.mp4 https://www.youtube.com/embed/dOFCeNPJhsE 112 2026-10-09T14:55:32+00:00 yes https://xdme.com/watch-book25-q103.html https://xdme.com/book25-thumbs/page-103.jpg Why are cities switching to LED streetlights with warmer colors? LED streetlights use about half the electricity of older lamps and last much longer, so cities save money. Because they can be aimed downward, they waste less light into the sky. Cooler, bluer light makes more glare and bothers animals and sleep more, so many cities now choose warmer, amber-toned LEDs. Smart design means lighting where it is needed. https://socialmedia.xdme.com/tony/videos-book25/page-103.mp4 https://www.youtube.com/embed/B-cMBy5cFRc 110 2026-10-09T14:55:33+00:00 yes https://xdme.com/watch-book25-q104.html https://xdme.com/book25-thumbs/page-104.jpg How do smart streetlights know when to dim? Smart streetlights have sensors that notice motion, daylight, and traffic. When nobody is around late at night, the lights can dim to save energy and then brighten when someone approaches. They can also be controlled from a computer, which reports when a bulb needs repair. Careful use of light saves energy and keeps streets safe. https://socialmedia.xdme.com/tony/videos-book25/page-104.mp4 https://www.youtube.com/embed/l1op_4JaIPg 109 2026-10-09T14:55:34+00:00 yes https://xdme.com/watch-book25-q105.html https://xdme.com/book25-thumbs/page-105.jpg Why are cities so noisy? Cities have many sounds: cars, buses, trains, planes, construction, sirens, music, and people talking. Sound bounces off tall buildings and pavement, so it stays loud between buildings. Hard surfaces reflect noise, while soft things like grass and trees soak up some. Cities try to reduce noise to help people sleep, learn, and feel calm. https://socialmedia.xdme.com/tony/videos-book25/page-105.mp4 https://www.youtube.com/embed/AK0RJFNhK9M 112 2026-10-09T14:55:35+00:00 yes https://xdme.com/watch-book25-q106.html https://xdme.com/book25-thumbs/page-106.jpg Why do cities have quiet hours and noise rules? Loud noise at night can wake people up, and sleep is important for growing and learning. That is why many cities have noise rules, called bylaws, that limit things like construction, leaf blowers, and loud music during late-night and early-morning hours. Quiet zones near hospitals and schools help patients rest and students think. Emergency work, like fixing a broken water pipe, can be allowed at any hour. https://socialmedia.xdme.com/tony/videos-book25/page-106.mp4 https://www.youtube.com/embed/AfZ6E7AAgZs 114 2026-10-09T14:55:36+00:00 yes https://xdme.com/watch-book25-q107.html https://xdme.com/book25-thumbs/page-107.jpg How do walls along highways block noise? A noise barrier is a tall, thick wall that stands between a road and nearby homes. Sound travels in straight lines, so the wall blocks the direct path, and some sound is absorbed or reflected back. The sound that does reach the homes is quieter. Walls work best when they are tall and without gaps. Earth mounds with trees can also help. https://socialmedia.xdme.com/tony/videos-book25/page-107.mp4 https://www.youtube.com/embed/p_wB8-oXdHc 105 2026-10-09T14:55:37+00:00 yes https://xdme.com/watch-book25-q108.html https://xdme.com/book25-thumbs/page-108.jpg How do thick windows keep city noise out? Sound is a vibration, and glass vibrates when sound hits it. Double and triple windows have two or three panes with a gap of air or gas between, and the panes are often different thicknesses. The vibrations lose energy as they pass from one pane to the next. Tight seals matter too, since sound sneaks through tiny gaps. That's why closing a window makes a room quieter. https://socialmedia.xdme.com/tony/videos-book25/page-108.mp4 https://www.youtube.com/embed/zIWYbdwVBNM 108 2026-10-09T14:58:38+00:00 yes https://xdme.com/watch-book25-q109.html https://xdme.com/book25-thumbs/page-109.jpg What is a soundscape, and how can you listen to one? A soundscape is all the sounds of a place together, such as birds, wind, footsteps, traffic, and music. Scientists record soundscapes to learn about the health of a place. You can take a sound walk with a grown-up. Walk slowly and listen for different kinds of sounds. If you want to close your eyes to listen better, stop and stand still first, away from the street. https://socialmedia.xdme.com/tony/videos-book25/page-109.mp4 https://www.youtube.com/embed/urvii9Cxn18 103 2026-10-09T15:01:40+00:00 yes https://xdme.com/watch-book25-q110.html https://xdme.com/book25-thumbs/page-110.jpg What is smog? The word smog comes from smoke and fog. Today it mostly means a haze of ozone and tiny particles. Ground-level ozone forms when sunlight reacts with gases from vehicles and factories. Smog is thickest on hot, sunny, still days and can make it harder to breathe. Cleaner cars, better fuels, and rules for factories have helped reduce it in many cities. https://socialmedia.xdme.com/tony/videos-book25/page-110.mp4 https://www.youtube.com/embed/x2RFITfbhio 110 2026-10-09T15:01:40+00:00 yes https://xdme.com/watch-book25-q111.html https://xdme.com/book25-thumbs/page-111.jpg Where does city air pollution come from? The main sources are vehicles, heating buildings, power plants, factories, construction dust, and wood smoke. Some pollution is made of gases, and some is tiny particles, called fine particles, about thirty times thinner than a hair. People breathing them can have a cough or tired lungs. Using fewer vehicles and cleaner energy helps keep air healthy. https://socialmedia.xdme.com/tony/videos-book25/page-111.mp4 https://www.youtube.com/embed/8E-Sjv3LvQk 109 2026-10-09T15:01:41+00:00 yes https://xdme.com/watch-book25-q112.html https://xdme.com/book25-thumbs/page-112.jpg How do scientists measure the quality of the air? Air-monitoring stations pull air through instruments that count tiny particles and measure gases such as ozone. In Canada, the numbers are combined into the Air Quality Health Index, a scale from 1 to 10 or more. Low numbers mean clean air, and high numbers mean people should take it easy outdoors. Checking the index helps you plan your day. https://socialmedia.xdme.com/tony/videos-book25/page-112.mp4 https://www.youtube.com/embed/kyhZc77u4XI 106 2026-10-09T15:01:42+00:00 yes https://xdme.com/watch-book25-q113.html https://xdme.com/book25-thumbs/page-113.jpg Why can smoke from faraway wildfires reach a city? Big wildfires send smoke high into the air, where strong winds can carry it for hundreds or even thousands of miles. In 2023, smoke from Canadian fires turned skies orange in New York City. The tiny particles in smoke can bother eyes and lungs. On smoky days, stay inside with windows closed, use air filters if you have them, and check the air quality. https://socialmedia.xdme.com/tony/videos-book25/page-113.mp4 https://www.youtube.com/embed/hM5Oe2zXPlo 114 2026-10-09T15:01:43+00:00 yes https://xdme.com/watch-book25-q114.html https://xdme.com/book25-thumbs/page-114.jpg How does a garbage truck squeeze in so much trash? A garbage truck has a strong hydraulic arm that lifts bins and dumps them into the back. Inside, a big metal plate called a packer blade pushes the trash forward against the wall and squeezes it into a smaller space. Liquid pressure in cylinders gives it great power. Compacting lets the truck carry much more on each trip. https://socialmedia.xdme.com/tony/videos-book25/page-114.mp4 https://www.youtube.com/embed/3_2RfL3H_rY 105 2026-10-09T15:01:43+00:00 yes https://xdme.com/watch-book25-q115.html https://xdme.com/book25-thumbs/page-115.jpg Why do aluminum cans jump off a belt at the recycling plant? At a recycling plant, items ride along a conveyor belt. Giant magnets lift out steel cans, but aluminum is not magnetic. So the plant uses a fast-spinning magnet at the end of the belt. It creates swirling electric currents inside each aluminum can, and those currents make the can act like a magnet that is pushed away. The cans leap forward into their own bin, while paper and glass fall straight down. https://socialmedia.xdme.com/tony/videos-book25/page-115.mp4 https://www.youtube.com/embed/rPY-5WGEOh8 112 2026-10-09T15:01:45+00:00 yes https://xdme.com/watch-book25-q116.html https://xdme.com/book25-thumbs/page-116.jpg What is a modern landfill like? A modern landfill is a carefully engineered site, not just a dump. It starts with a thick liner of clay and plastic to keep liquids from soaking into the ground. Trash is spread, squashed, and covered with soil each day. Pipes collect the liquid that drains through the trash and the gas, called methane, which can be burned to make electricity. After closing, many landfills become parks. https://socialmedia.xdme.com/tony/videos-book25/page-116.mp4 https://www.youtube.com/embed/Hyie4uVdztw 112 2026-10-09T15:01:45+00:00 yes https://xdme.com/watch-book25-q117.html https://xdme.com/book25-thumbs/page-117.jpg Why can't everything go in the blue bin? Recycling works best when the items are clean and the right type. Greasy pizza boxes, food-covered containers, and plastic bags can spoil other paper or jam machines. Some plastics have no buyers. Cities have rules that list what is accepted, so check your local guide. Rinsing containers and keeping bins free of the wrong things helps recycling work. https://socialmedia.xdme.com/tony/videos-book25/page-117.mp4 https://www.youtube.com/embed/EgHgukOCXIA 107 2026-10-09T15:01:46+00:00 yes https://xdme.com/watch-book25-q118.html https://xdme.com/book25-thumbs/page-118.jpg How does a city turn green-bin scraps into compost and energy? Trucks bring green-bin scraps to a processing plant. Workers and machines pull out bags and plastic, and then the scraps go into huge sealed tanks called digesters. With no air inside, tiny microbes break down the food and give off a gas called biogas, which can be used for heat or to fuel trucks. What is left is cured into compost that can enrich soil. https://socialmedia.xdme.com/tony/videos-book25/page-118.mp4 https://www.youtube.com/embed/s9TNfUjSv6M 108 2026-10-09T15:01:47+00:00 yes https://xdme.com/watch-book25-q119.html https://xdme.com/book25-thumbs/page-119.jpg Why does a plastic bottle left outside last for hundreds of years? Plastic is made from long chains of molecules that bacteria and fungi do not know how to eat. In sunlight and weather, plastic breaks into smaller and smaller pieces, but the pieces don't disappear. They become tiny bits called microplastics. That is why it is best to reuse plastic, recycle it, and never litter. Picking up litter helps keep parks and streams clean. https://socialmedia.xdme.com/tony/videos-book25/page-119.mp4 https://www.youtube.com/embed/cxzlZR4_Ogs 112 2026-10-09T15:01:48+00:00 yes https://xdme.com/watch-book25-q120.html https://xdme.com/book25-thumbs/page-120.jpg How do street sweepers clean the road? A street sweeper has round brushes underneath that spin and sweep dirt toward the middle. A conveyor or vacuum lifts the debris into a storage bin. Sprays of water keep dust from rising. Sweepers keep litter, sand, and leaves out of the storm drains and rivers. They often work at night or early in the morning when there is less traffic. https://socialmedia.xdme.com/tony/videos-book25/page-120.mp4 https://www.youtube.com/embed/gBB8urhrsL4 106 2026-10-09T15:01:49+00:00 yes https://xdme.com/watch-book25-q121.html https://xdme.com/book25-thumbs/page-121.jpg How do snowplows and salt trucks clear the road? A snowplow has a big angled blade that pushes snow to the side. Many also spread salt or sand from the back. Crews watch the weather and plan routes with GPS so they can clear major roads first. Small plows clear sidewalks and bike paths. Stay far away from plows, since the drivers might not see you, and never play in the snow piles. https://socialmedia.xdme.com/tony/videos-book25/page-121.mp4 https://www.youtube.com/embed/Cfpj3G7VKX0 109 2026-10-09T15:01:50+00:00 yes https://xdme.com/watch-book25-q122.html https://xdme.com/book25-thumbs/page-122.jpg Why is too much road salt a problem? When snow melts, salty water washes into storm drains, streams, lakes, and soil. Too much salt can harm fish, trees, and drinking water. It can also rust cars and bridges and make a dog’s paws sore. Cities use the right amounts, spray salty water before storms, or mix in sand. Shoveling early helps use less salt. Some places have tried beet juice to help salt work better. https://socialmedia.xdme.com/tony/videos-book25/page-122.mp4 https://www.youtube.com/embed/lSQMwo3YFEw 111 2026-10-09T15:01:51+00:00 yes https://xdme.com/watch-book25-q123.html https://xdme.com/book25-thumbs/page-123.jpg What should happen to old phones and computers? Old electronics, called e-waste, contain valuable metals like copper and gold, and some materials that should not end up in a landfill. Many places have special drop-off events or stores that collect them for recycling or repair. Never throw batteries in the trash, since they can start fires. Giving working devices to someone who needs them is the best choice. https://socialmedia.xdme.com/tony/videos-book25/page-123.mp4 https://www.youtube.com/embed/VgOUxtV-NyM 111 2026-10-09T15:01:52+00:00 yes https://xdme.com/watch-book25-q124.html https://xdme.com/book25-thumbs/page-124.jpg How can a neighborhood make less trash? Neighbors can share and repair instead of buying new. Some towns have repair cafés where volunteers fix toys and clothes, and libraries that lend tools. People bring cloth bags, compost food, and swap clothes. The idea is to reduce first, then reuse, then recycle. Less trash means less to carry, bury, or burn. https://socialmedia.xdme.com/tony/videos-book25/page-124.mp4 https://www.youtube.com/embed/Xwt7JrOHG_A 110 2026-10-09T15:01:53+00:00 yes https://xdme.com/watch-book25-q125.html https://xdme.com/book25-thumbs/page-125.jpg Why does a school bus flash its lights and swing out a stop sign? A school bus uses its lights to warn other drivers that children are getting on or off. Yellow or amber lights flash first, which means get ready to stop. When the bus stops, red lights flash and a stop sign swings out from the side. Drivers must stop and stay stopped, and in many places they must stop from both directions. Never walk in front of a bus without the driver seeing you. https://socialmedia.xdme.com/tony/videos-book25/page-125.mp4 https://www.youtube.com/embed/EX3QN8ycDDE 113 2026-10-09T15:01:53+00:00 yes https://xdme.com/watch-book25-q126.html https://xdme.com/book25-thumbs/page-126.jpg What did the very first cities look like? About 10,000 years ago, people began farming and could grow more food than they needed. Villages grew into towns with houses packed close together. One early town, Çatalhöyük in present-day Turkey, had homes entered from the roof. About 5,000 years ago, Uruk in Mesopotamia had tens of thousands of people, markets, and one of the first kinds of writing, used to keep records. https://socialmedia.xdme.com/tony/videos-book25/page-126.mp4 https://www.youtube.com/embed/MhxsIBvYw_s 113 2026-10-09T15:01:54+00:00 yes https://xdme.com/watch-book25-q127.html https://xdme.com/book25-thumbs/page-127.jpg How did ancient Romans bring water to their cities? The Romans built aqueducts, which were long channels that carried water from springs and rivers far away. They sloped very gently downhill so gravity could do the work, and tall stone arches carried them across valleys. Some are still standing. Water arrived at public fountains and baths. Engineers needed careful measuring skills to keep the slope just right. https://socialmedia.xdme.com/tony/videos-book25/page-127.mp4 https://www.youtube.com/embed/neH7RjzvuaE 112 2026-10-09T15:01:55+00:00 yes https://xdme.com/watch-book25-q128.html https://xdme.com/book25-thumbs/page-128.jpg How did elevators and cars change the way cities grew? Before elevators and steel frames, buildings were rarely taller than about six stories because people had to climb stairs. After elevators, cities grew upward. Later, when cars became common, roads became wider and people could live farther from work, so cities spread outward into suburbs. Subways, buses, and trains helped people travel in crowded places. https://socialmedia.xdme.com/tony/videos-book25/page-128.mp4 https://www.youtube.com/embed/Vnzn8-iD6bw 111 2026-10-09T15:01:56+00:00 yes https://xdme.com/watch-book25-q129.html https://xdme.com/book25-thumbs/page-129.jpg Why do some cities have a grid of streets and others wind around? A grid is easy to plan, easy to map, and easy to divide into building lots, so many cities, like Toronto and Chicago, use it. Winding streets often grew from old paths, hills, rivers, and coastlines in places like old European towns. Grids make it simple to find your way, while curves can slow cars and add charm. Each pattern has good points. https://socialmedia.xdme.com/tony/videos-book25/page-129.mp4 https://www.youtube.com/embed/ILC5hulfd5k 107 2026-10-09T15:01:57+00:00 yes https://xdme.com/watch-book25-q130.html https://xdme.com/book25-thumbs/page-130.jpg What do city planners do? City planners think about how a city can grow in a healthy way. They study maps, population numbers, traffic, parks, and land. They help decide where homes, shops, schools, and roads should go, and plan for the next 20 or 30 years. Planners also listen to what many different neighbors need. It is like putting together a giant puzzle. https://socialmedia.xdme.com/tony/videos-book25/page-130.mp4 https://www.youtube.com/embed/Ykn8vWpnupk 106 2026-10-09T15:01:58+00:00 yes https://xdme.com/watch-book25-q131.html https://xdme.com/book25-thumbs/page-131.jpg What is a zoning map? A zoning map shows what kinds of buildings are allowed in each part of a city, such as homes, shops, offices, factories, or parks. It helps keep noisy or smelly places away from bedrooms and makes sure there is room for everything. Some zones mix homes and shops so people can walk to stores. Planners adjust the map as the city changes. https://socialmedia.xdme.com/tony/videos-book25/page-131.mp4 https://www.youtube.com/embed/eFW1AdEdXvM 107 2026-10-09T15:01:59+00:00 yes https://xdme.com/watch-book25-q132.html https://xdme.com/book25-thumbs/page-132.jpg How do planners decide where a new school or park should go? Planners count how many families and children live nearby and look at the distances people would need to walk. A common goal is to place parks and schools within a short walk, about ten minutes, for most families. They also check whether the roads are safe and whether there is enough land. They ask neighbors for their ideas too. https://socialmedia.xdme.com/tony/videos-book25/page-132.mp4 https://www.youtube.com/embed/MnwIiQjcSKI 102 2026-10-09T15:02:00+00:00 yes https://xdme.com/watch-book25-q133.html https://xdme.com/book25-thumbs/page-133.jpg What is population density? Population density tells how many people live in a certain area, such as per square mile or square kilometer. Dense places, like downtown Toronto, have many people in a small area. Toronto has about 4,000 people per square kilometer, while all of Canada averages only about four. Dense neighborhoods can share buses, shops, and pipes more easily. https://socialmedia.xdme.com/tony/videos-book25/page-133.mp4 https://www.youtube.com/embed/QCMkCSFYb2Y 115 2026-10-09T15:02:01+00:00 yes https://xdme.com/watch-book25-q134.html https://xdme.com/book25-thumbs/page-134.jpg How do map layers help planners? Planners use computer mapping, called GIS. Each layer of the map shows one kind of information: roads, pipes, trees, parks, flood zones, or buildings. By stacking layers, planners can see where problems and opportunities lie. For example, they can find areas far from parks or places likely to flood. Maps help them make wise choices. https://socialmedia.xdme.com/tony/videos-book25/page-134.mp4 https://www.youtube.com/embed/Ahcna3K9qt4 108 2026-10-09T15:02:03+00:00 yes https://xdme.com/watch-book25-q135.html https://xdme.com/book25-thumbs/page-135.jpg What is the difference between a city growing up and growing out? When a city grows outward, it uses more land, so houses, roads, and pipes spread farther apart. This can mean longer trips and more driving. When it grows upward, with taller buildings, more people live close to shops and transit, using less land. Most cities do a mix. Planners try to balance parks, farms, and homes. https://socialmedia.xdme.com/tony/videos-book25/page-135.mp4 https://www.youtube.com/embed/jwzahi8hmVo 107 2026-10-09T15:02:03+00:00 yes https://xdme.com/watch-book25-q136.html https://xdme.com/book25-thumbs/page-136.jpg Why do cities protect old buildings? Old buildings tell the story of a city and make it special. Their materials and craftsmanship are often beautiful, and reusing them saves resources. Cities can protect them with heritage rules and find new uses for them. In Toronto, old factory buildings in the Distillery District now hold shops and studios. A city with history feels like a place with memories. https://socialmedia.xdme.com/tony/videos-book25/page-136.mp4 https://www.youtube.com/embed/4a4hcbDfR80 110 2026-10-09T15:02:04+00:00 yes https://xdme.com/watch-book25-q137.html https://xdme.com/book25-thumbs/page-137.jpg How do cities get ready for heavy storms and floods? Cities build bigger storm pipes, ponds that store extra water, and pumps to move it away. Underground tanks hold extra water, and some streets are designed to hold water briefly. Weather forecasts give warnings so crews can prepare. Walls or barriers protect low areas. The aim is to give the rain somewhere to go that is not your basement. https://socialmedia.xdme.com/tony/videos-book25/page-137.mp4 https://www.youtube.com/embed/jSoV9ZUH4A4 108 2026-10-09T15:02:05+00:00 yes https://xdme.com/watch-book25-q138.html https://xdme.com/book25-thumbs/page-138.jpg What helps a city stay cool during a heat wave? Shade trees, parks, and light-colored roofs keep cities cooler. Cities open cooling centers in libraries and community centers, set up water fountains, and run splash pads. People can drink water, rest in the shade, and check on neighbors. Warm nights are hard for people, so cooling matters. Planning for heat helps everyone. https://socialmedia.xdme.com/tony/videos-book25/page-138.mp4 https://www.youtube.com/embed/pmVtczb4EPw 106 2026-10-09T15:02:06+00:00 yes https://xdme.com/watch-book25-q139.html https://xdme.com/book25-thumbs/page-139.jpg What makes a city a good place for kids? A kid-friendly city has safe sidewalks and crossings, parks and playgrounds, libraries, bike paths, and places to meet friends. Slow traffic near schools, shade, and clean air make playing outdoors easier. Planners sometimes ask children for ideas, because kids notice things grown-ups miss. Walking and playing outside help bodies and minds grow strong. https://socialmedia.xdme.com/tony/videos-book25/page-139.mp4 https://www.youtube.com/embed/Mneb1XQt_2A 108 2026-10-09T15:02:07+00:00 yes https://xdme.com/watch-book25-q140.html https://xdme.com/book25-thumbs/page-140.jpg What is a smart city? A smart city uses sensors and computers to help things run better. Sensors can count traffic, find water leaks, track free parking spots, or warn of floods. Apps share bus arrival times. The information helps workers fix problems faster and plan better. Cities also need to keep people's personal information private and safe. https://socialmedia.xdme.com/tony/videos-book25/page-140.mp4 https://www.youtube.com/embed/knLF_7xfY7E 108 2026-10-09T15:02:09+00:00 yes https://xdme.com/watch-book25-q141.html https://xdme.com/book25-thumbs/page-141.jpg How do bike-share systems work? In a bike-share system, you can borrow a bike from a station, ride it to another station, and lock it back. You usually unlock it with a card or an app. A computer tracks which bikes are where. Workers move bikes from busy stations to empty ones, and check brakes and tires. Always wear a helmet and follow the traffic rules. https://socialmedia.xdme.com/tony/videos-book25/page-141.mp4 https://www.youtube.com/embed/gvpBFYN3lk4 104 2026-10-09T15:02:09+00:00 yes https://xdme.com/watch-book25-q142.html https://xdme.com/book25-thumbs/page-142.jpg How can kids help design their city? Many cities invite kids to share their ideas. Children build models, draw maps, or make suggestions about parks and streets. A program called Block by Block lets young people design public spaces in the game Minecraft, and planners have used their ideas. Kids know what they need and what is missing. Everyone can help make a better city. https://socialmedia.xdme.com/tony/videos-book25/page-142.mp4 https://www.youtube.com/embed/nbb9xSpJCKM 108 2026-10-09T15:02:11+00:00 yes https://xdme.com/watch-book25-q143.html https://xdme.com/book25-thumbs/page-143.jpg How do planners test a city design before it's built? Computers can simulate how people and cars would move, how sunlight and shadow would fall, or how a flood would flow through the streets. Planners can change a plan and run the test again at no cost. Small models and virtual reality also help them imagine the place. Testing first means mistakes are found early, when they are easy to fix. https://socialmedia.xdme.com/tony/videos-book25/page-143.mp4 https://www.youtube.com/embed/-bkyyeGgkvE 111 2026-10-09T15:02:11+00:00 yes https://xdme.com/watch-book25-q144.html https://xdme.com/book25-thumbs/page-144.jpg Why do some cities leave a ring of green land around them? A greenbelt is a ring of protected farms, forests, and wetlands around a city. It stops the city from spreading forever, keeps farmland and nature close to people, and protects rivers and drinking water. It also gives people nearby places to hike or picnic. Ottawa has one, and Ontario protects a huge Greenbelt around the Toronto region. Protected land helps wildlife and cleans the air. https://socialmedia.xdme.com/tony/videos-book25/page-144.mp4 https://www.youtube.com/embed/yZVi-Ilev6Q 111 2026-10-09T15:02:12+00:00 yes https://xdme.com/watch-book25-q145.html https://xdme.com/book25-thumbs/page-145.jpg Why do neighborhoods in the same city feel so different? Each neighborhood grows from its own history, buildings, and people. Streets might be lined with old houses, tall apartments, or shops, and different groups bring their foods, languages, music, and festivals. Hills, rivers, and parks shape each area as well. These differences are what make a big city interesting to explore. https://socialmedia.xdme.com/tony/videos-book25/page-145.mp4 https://www.youtube.com/embed/OneYhAnNdtc 114 2026-10-09T15:02:13+00:00 yes https://xdme.com/watch-book25-q146.html https://xdme.com/book25-thumbs/page-146.jpg Why do cities have public art? Murals, statues, mosaics, and light displays make streets friendlier and tell a community's stories. Public art can brighten a plain wall or turn a utility box into a masterpiece. Artists use paints and materials that must stand up to sun, rain, and snow. Art gives people a reason to stop, look, and talk to each other. https://socialmedia.xdme.com/tony/videos-book25/page-146.mp4 https://www.youtube.com/embed/_SycmtDBqdA 109 2026-10-09T15:02:14+00:00 yes https://xdme.com/watch-book25-q147.html https://xdme.com/book25-thumbs/page-147.jpg How do cities make streets easier for everyone to use? Good city design helps people with different needs. Curb cuts are sloped sidewalk edges, first made for wheelchairs, that also help strollers, carts, and bikes. Bumpy tiles warn people with low vision about crossings, and talking signals help them cross. Ramps, wide doors, and elevators make buildings open to all. This is called universal design, because it works for everybody. https://socialmedia.xdme.com/tony/videos-book25/page-147.mp4 https://www.youtube.com/embed/bn-83OnKmew 111 2026-10-09T15:02:15+00:00 yes https://xdme.com/watch-book25-q148.html https://xdme.com/book25-thumbs/page-148.jpg Why do so many people in cities live in apartments? In a crowded city, land is limited and expensive. Apartments stack homes on top of each other so that more families can live close to work, schools, and shops. Shared walls and floors keep buildings warmer, because there is less outer wall exposed to the cold. Many people can share the same elevator, heating system, and water pipes. https://socialmedia.xdme.com/tony/videos-book25/page-148.mp4 https://www.youtube.com/embed/6HLVVLgA7SI 109 2026-10-09T15:02:16+00:00 yes https://xdme.com/watch-book25-q149.html https://xdme.com/book25-thumbs/page-149.jpg How will today's kids shape the cities of tomorrow? The cities of the future will be built, run, and improved by people who are kids today. They will invent cleaner transport, smarter buildings, and new ways to share water and energy. Learning about science, math, and nature helps. Even now, you can notice problems in your city and imagine ways to fix them. https://socialmedia.xdme.com/tony/videos-book25/page-149.mp4 https://www.youtube.com/embed/s4-hY31ss1Q 111 2026-10-09T15:02:17+00:00 yes https://xdme.com/watch-book25-q150.html https://xdme.com/book25-thumbs/page-150.jpg How do all the city systems fit together like one giant machine? A city works because many systems connect. Buildings need water and power, streets need lights and signs, and trash trucks and sewers keep things clean. Parks and trees support wildlife and cool the air, while planners and workers keep everything going. When one part changes, it affects the others. A city is a living puzzle that people keep solving together. https://socialmedia.xdme.com/tony/videos-book25/page-150.mp4 https://www.youtube.com/embed/9CBtU_TBy3Q 109 2026-10-09T15:02:18+00:00 yes https://xdme.com/watch-book26-q001.html https://xdme.com/book26-thumbs/page-001.jpg What is a happy accident in science? A happy accident is a surprise that leads to a useful discovery. Scientists call it serendipity, a word from an old tale about three princes who kept finding things they were not looking for. The surprise alone is not enough, though. Someone has to notice it, wonder why it happened, and test it. Many great inventions started this way. https://socialmedia.xdme.com/tony/videos-book26/page-001.mp4 https://www.youtube.com/embed/JxDnwBbX4ac 109 2026-10-09T14:43:28+00:00 yes https://xdme.com/watch-book26-q002.html https://xdme.com/book26-thumbs/page-002.jpg How did a melted chocolate bar lead to the microwave oven? In 1945, engineer Percy Spencer was working near a machine that makes microwaves when he noticed the chocolate bar in his pocket had melted. Curious, he held popcorn kernels near the machine, and they popped. Then he tried an egg, which cooked. Soon his company built the first microwave oven. It was as tall as a grown-up and very heavy. https://socialmedia.xdme.com/tony/videos-book26/page-002.mp4 https://www.youtube.com/embed/Fka6167ryiI 109 2026-10-09T14:43:29+00:00 yes https://xdme.com/watch-book26-q003.html https://xdme.com/book26-thumbs/page-003.jpg How did a moldy dish lead to the first antibiotic? In 1928, scientist Alexander Fleming came back from vacation and found mold growing on one of his dishes of bacteria. Around the mold, the bacteria had died. He realized the mold was making something that kills germs. Years later, other scientists turned it into the medicine penicillin. Never touch or sniff moldy things yourself, because only trained scientists study them safely. https://socialmedia.xdme.com/tony/videos-book26/page-003.mp4 https://www.youtube.com/embed/fhT_RgcU8X0 111 2026-10-09T14:43:30+00:00 yes https://xdme.com/watch-book26-q004.html https://xdme.com/book26-thumbs/page-004.jpg How did a weak glue become sticky notes? In 1968, a scientist named Spencer Silver at 3M tried to make a super-strong glue but made one that barely stuck. For years nobody knew what to do with it. Then a coworker, Art Fry, was annoyed when the paper bookmarks in his song book kept falling out. He used the weak glue to make bookmarks that stuck and peeled off cleanly. Sticky notes were born. https://socialmedia.xdme.com/tony/videos-book26/page-004.mp4 https://www.youtube.com/embed/fVEQ5UsDyuA 104 2026-10-09T14:43:31+00:00 yes https://xdme.com/watch-book26-q005.html https://xdme.com/book26-thumbs/page-005.jpg Why was bubble wrap first meant to be wallpaper? In 1957, two inventors, Al Fielding and Marc Chavannes, sealed two plastic shower curtains together to make a bumpy wall covering. Nobody wanted it. Next, they tried it as greenhouse insulation, but that did not work either. Finally, a company realized the bubbles would be great at cushioning fragile things during shipping. A failed wallpaper became a famous packing material. https://socialmedia.xdme.com/tony/videos-book26/page-005.mp4 https://www.youtube.com/embed/fUZs9Lg6sPY 111 2026-10-09T14:43:33+00:00 yes https://xdme.com/watch-book26-q006.html https://xdme.com/book26-thumbs/page-006.jpg How was rubber made stronger by accident? Natural rubber gets sticky in heat and stiff in cold. In 1839, inventor Charles Goodyear found that heating rubber with sulfur made it firm, tough, and stretchy in all weather. A popular story says he spilled a mix onto a hot stove and it charred but stayed bouncy. In England, Thomas Hancock got a patent for a similar process in 1843. This is how tires, boots, and bouncing balls became dependable. https://socialmedia.xdme.com/tony/videos-book26/page-006.mp4 https://www.youtube.com/embed/f11wfyS8IDU 111 2026-10-09T14:43:34+00:00 yes https://xdme.com/watch-book26-q007.html https://xdme.com/book26-thumbs/page-007.jpg How did a mistake lead to Silly Putty? In the early 1940s, scientists were searching for a cheap, bouncy substitute for rubber. In one lab, James Wright mixed silicone oil with another chemical and got a strange goo. It bounced like rubber and stretched like taffy but didn't work as a rubber substitute. Years later, a toy seller put it in plastic eggs, and it became a toy. https://socialmedia.xdme.com/tony/videos-book26/page-007.mp4 https://www.youtube.com/embed/g3pwtNgoMDA 105 2026-10-09T14:43:35+00:00 yes https://xdme.com/watch-book26-q008.html https://xdme.com/book26-thumbs/page-008.jpg How did a spring that fell off a shelf become the Slinky? In 1943, engineer Richard James was testing springs for ship equipment when one fell off a shelf. Instead of landing in a heap, it flipped end over end and walked across the floor. He thought it would make a great toy. His wife named it the Slinky. It first went on sale in 1945, and the toy sold out quickly. https://socialmedia.xdme.com/tony/videos-book26/page-008.mp4 https://www.youtube.com/embed/xtcWcHwMgs8 102 2026-10-09T14:43:37+00:00 yes https://xdme.com/watch-book26-q009.html https://xdme.com/book26-thumbs/page-009.jpg How did Play-Doh start as a wall cleaner? When coal was used to heat many homes, wallpaper got sooty. A soft, dough-like putty was invented in the 1930s to rub the soot off. Later, homes switched to other kinds of heat and the cleaner stopped selling. Then a teacher noticed that kids loved to model with it. It was renamed Play-Doh in the 1950s and became a toy. https://socialmedia.xdme.com/tony/videos-book26/page-009.mp4 https://www.youtube.com/embed/qBQdmQmLut8 101 2026-10-09T14:43:38+00:00 yes https://xdme.com/watch-book26-q010.html https://xdme.com/book26-thumbs/page-010.jpg Who invented the ice cream cone? Stories differ. Many people say that at the 1904 World’s Fair in St. Louis, an ice cream seller ran out of dishes. A waffle maker named Ernest Hamwi, in a booth next to him, rolled one of his thin waffles into a cone, and the ice cream fit inside. Others say an Italian inventor, Italo Marchiony, had a patent for a cone mold in 1903. Cones may have been invented in several places. https://socialmedia.xdme.com/tony/videos-book26/page-010.mp4 https://www.youtube.com/embed/Eq0axqUmdQA 111 2026-10-09T14:43:39+00:00 yes https://xdme.com/watch-book26-q011.html https://xdme.com/book26-thumbs/page-011.jpg Where did the chocolate chip cookie come from? In the 1930s, Ruth Wakefield ran the Toll House Inn in Massachusetts. A popular story says she added chunks of chocolate to cookie dough, expecting them to melt into the batter, but they stayed in bits. Some say she planned it. Either way, the chocolate chip cookie was a hit, and chocolate companies started selling chips. https://socialmedia.xdme.com/tony/videos-book26/page-011.mp4 https://www.youtube.com/embed/3VMrpDli6e0 104 2026-10-09T14:43:40+00:00 yes https://xdme.com/watch-book26-q012.html https://xdme.com/book26-thumbs/page-012.jpg How did cornflakes come about? In 1894, brothers John and Will Kellogg in Michigan were cooking wheat dough. They got distracted, and the dough sat for hours until it went stale. When they pressed it through rollers, it broke into flakes instead of a big sheet. They baked the flakes and served them. People liked them, and they later tried the same idea with corn. https://socialmedia.xdme.com/tony/videos-book26/page-012.mp4 https://www.youtube.com/embed/i_mRlIecOmo 102 2026-10-09T14:43:41+00:00 yes https://xdme.com/watch-book26-q013.html https://xdme.com/book26-thumbs/page-013.jpg How were X-rays discovered by accident? In 1895, German physicist Wilhelm Röntgen was working in a dark room with a tube covered in black paper. He noticed a screen across the room glowing, even though no light could escape. He realized an invisible kind of ray was passing through the paper. He called them X-rays because he did not know what they were. Soon doctors used them to see bones. https://socialmedia.xdme.com/tony/videos-book26/page-013.mp4 https://www.youtube.com/embed/M2MOwqlWudQ 107 2026-10-09T14:43:42+00:00 yes https://xdme.com/watch-book26-q014.html https://xdme.com/book26-thumbs/page-014.jpg How did a dropped flask lead to safety glass? In 1903, French scientist Édouard Bénédictus knocked a glass flask off a shelf. It cracked but did not shatter, because it had a thin plastic coating inside. He figured out that glass with a layer of plastic held together when broken. This became laminated safety glass, which is used in car windshields to keep pieces from flying. https://socialmedia.xdme.com/tony/videos-book26/page-014.mp4 https://www.youtube.com/embed/5Fh8JK1euxQ 108 2026-10-09T14:43:43+00:00 yes https://xdme.com/watch-book26-q015.html https://xdme.com/book26-thumbs/page-015.jpg How was stainless steel discovered? In 1913, a metal expert named Harry Brearley in England was testing steels to find one that wore well. He tossed away a sample that did not seem useful. Weeks later, he noticed it had not rusted, while the others had. It contained a metal called chromium, which forms a thin invisible skin that protects steel. Stainless steel is used in knives, forks, and sinks. https://socialmedia.xdme.com/tony/videos-book26/page-015.mp4 https://www.youtube.com/embed/kQT1Md47sG0 107 2026-10-09T14:43:44+00:00 yes https://xdme.com/watch-book26-q016.html https://xdme.com/book26-thumbs/page-016.jpg How did a mystery cylinder of gas lead to Teflon? In 1938, chemist Roy Plunkett was working with a gas stored in a cylinder. When he opened it, no gas came out, but the cylinder still weighed the same. Curious, he cut it open and found a slippery white powder inside. It turned out to be a new plastic that nothing would stick to. It became the coating on nonstick pans. https://socialmedia.xdme.com/tony/videos-book26/page-016.mp4 https://www.youtube.com/embed/FKsUSd1Xdws 105 2026-10-09T14:43:45+00:00 yes https://xdme.com/watch-book26-q017.html https://xdme.com/book26-thumbs/page-017.jpg How did a wrong part help invent the pacemaker? In 1956, engineer Wilson Greatbatch was building a machine to record heartbeats. By mistake, he reached for the wrong part. When he turned it on, the circuit made steady pulses, like a heartbeat. He realized it could help a heart that beats unevenly. Within a few years, the first small pacemakers were put into people to keep their hearts steady. https://socialmedia.xdme.com/tony/videos-book26/page-017.mp4 https://www.youtube.com/embed/ERsmkpPaWFI 105 2026-10-09T14:43:46+00:00 yes https://xdme.com/watch-book26-q018.html https://xdme.com/book26-thumbs/page-018.jpg How was Super Glue discovered? In 1942, chemist Harry Coover was looking for a clear plastic when he made a chemical that stuck to everything it touched. It was too sticky to use, so he set it aside. Years later, he realized the sticky stuff could be a wonderful glue. Super Glue sticks very quickly and strongly. Kids should never use it without a grown-up. https://socialmedia.xdme.com/tony/videos-book26/page-018.mp4 https://www.youtube.com/embed/hGNf6GW2RCs 102 2026-10-09T14:43:48+00:00 yes https://xdme.com/watch-book26-q019.html https://xdme.com/book26-thumbs/page-019.jpg How did a noisy antenna reveal the afterglow of the Big Bang? In 1964, scientists Arno Penzias and Robert Wilson were using a huge horn-shaped antenna in New Jersey. They heard a steady hiss that would not go away. They cleaned out pigeon droppings and checked everything, but the hiss stayed. It was ancient heat left from the early universe, the cosmic microwave background. They earned a Nobel Prize for the discovery. https://socialmedia.xdme.com/tony/videos-book26/page-019.mp4 https://www.youtube.com/embed/63TcAa-fHHM 110 2026-10-09T14:43:49+00:00 yes https://xdme.com/watch-book26-q020.html https://xdme.com/book26-thumbs/page-020.jpg What does it mean that chance favors the prepared mind? Chemist Louis Pasteur said that chance favors the prepared mind. Lots of people see surprising things, but those who know a lot, ask good questions, and pay attention can turn surprises into discoveries. Fleming noticed mold, and Röntgen noticed a glowing screen. Learning and being curious get you ready for lucky moments. https://socialmedia.xdme.com/tony/videos-book26/page-020.mp4 https://www.youtube.com/embed/pHrrrpYi0nk 109 2026-10-09T14:43:50+00:00 yes https://xdme.com/watch-book26-q021.html https://xdme.com/book26-thumbs/page-021.jpg Why do inventors keep notebooks? Notebooks help inventors remember their ideas, experiments, and surprises. They write dates, sketches, and notes about what worked and didn't. This helps them repeat a lucky accident, check mistakes, and show others how they did it. Thomas Edison filled thousands of notebooks. Your own notebook can be a treasure of ideas. https://socialmedia.xdme.com/tony/videos-book26/page-021.mp4 https://www.youtube.com/embed/oe0EyJRnK04 114 2026-10-09T14:43:51+00:00 yes https://xdme.com/watch-book26-q022.html https://xdme.com/book26-thumbs/page-022.jpg How can you tinker safely with a surprise at home? When something odd happens, don't throw it out. Stay safe, and ask a grown-up to help you look closer. Change only one thing at a time, like the amount of water in a mixture, and write down what you see. Stick to safe kitchen materials, such as flour, water, and cornstarch. Never mix cleaning products or taste experiments. https://socialmedia.xdme.com/tony/videos-book26/page-022.mp4 https://www.youtube.com/embed/6iH2xEkthkA 104 2026-10-09T14:43:52+00:00 yes https://xdme.com/watch-book26-q023.html https://xdme.com/book26-thumbs/page-023.jpg How did spilled wine lead to cellophane? Swiss chemist Jacques Brandenberger was in a restaurant in 1900 when someone spilled wine on a tablecloth. He thought, wouldn't it be useful to have cloth that wouldn't soak up spills? He tried coating cloth, and the coating peeled off as a thin, clear sheet. That sheet was cellophane. It was used for wrapping candy, food, and gifts. https://socialmedia.xdme.com/tony/videos-book26/page-023.mp4 https://www.youtube.com/embed/yVnnLV8lyhg 105 2026-10-09T14:43:53+00:00 yes https://xdme.com/watch-book26-q024.html https://xdme.com/book26-thumbs/page-024.jpg How did tea bags get started? A story says that around 1908, a tea seller named Thomas Sullivan sent samples to customers in little silk bags instead of tins. Some customers dropped the whole bag into hot water. They liked how easy it was, and asked for more. Later, makers switched to paper and gauze bags. A shipping idea became a way to make tea. https://socialmedia.xdme.com/tony/videos-book26/page-024.mp4 https://www.youtube.com/embed/PPRPhojk8Bk 104 2026-10-09T14:43:54+00:00 yes https://xdme.com/watch-book26-q025.html https://xdme.com/book26-thumbs/page-025.jpg How did a contest for billiard balls lead to plastic? In the 1860s, billiard balls were made from ivory, which was becoming rare. A company offered a prize for a substitute. Inventor John Wesley Hyatt took up the challenge and made celluloid, one of the first plastics, from plant fibers. Celluloid became combs, movie film, and collars. It was a start for the age of plastics. https://socialmedia.xdme.com/tony/videos-book26/page-025.mp4 https://www.youtube.com/embed/kQqTVnv4LmY 109 2026-10-09T14:43:56+00:00 yes https://xdme.com/watch-book26-q026.html https://xdme.com/book26-thumbs/page-026.jpg What is biomimicry? Biomimicry means copying ideas from nature to solve human problems. Plants and animals have been testing designs for millions of years, and the ones that work well survive. Engineers study how a bird flies, how a gecko sticks, or how a leaf stays clean, and then use those ideas in machines, buildings, and materials. Nature is full of inventors' clues. https://socialmedia.xdme.com/tony/videos-book26/page-026.mp4 https://www.youtube.com/embed/f2n69bBjr88 111 2026-10-09T14:43:57+00:00 yes https://xdme.com/watch-book26-q027.html https://xdme.com/book26-thumbs/page-027.jpg How did a walk with a dog lead to Velcro? In 1941, Swiss engineer George de Mestral came home from a walk in the Alps with burrs stuck to his clothes and his dog’s fur. He looked at one under a microscope and wondered if he could copy it. It took him years of tests with different cloths to get it right. He called his invention Velcro and got a patent in 1955. https://socialmedia.xdme.com/tony/videos-book26/page-027.mp4 https://www.youtube.com/embed/6EtNxApHWEE 109 2026-10-09T14:43:58+00:00 yes https://xdme.com/watch-book26-q028.html https://xdme.com/book26-thumbs/page-028.jpg How did a kingfisher help shape a fast train? Japan's high-speed trains made a loud boom when they zoomed out of tunnels, because they pushed air ahead like a piston. An engineer who watched birds noticed that a kingfisher dives into water with barely a splash. Its long, narrow beak slips smoothly from thin air into thick water. Copying that shape for the train's nose made it quieter and faster. https://socialmedia.xdme.com/tony/videos-book26/page-028.mp4 https://www.youtube.com/embed/CMLpBqoo2GI 106 2026-10-09T14:44:00+00:00 yes https://xdme.com/watch-book26-q029.html https://xdme.com/book26-thumbs/page-029.jpg How does a lotus leaf keep itself clean? A lotus leaf is covered with tiny bumps and a waxy coating. Water cannot spread, so it rolls into beads and runs off. As the drops roll, they pick up dirt and carry it away. This is called the lotus effect. Engineers copy it for self-cleaning paints, glass, and fabrics, so that rain can do some of the cleaning. https://socialmedia.xdme.com/tony/videos-book26/page-029.mp4 https://www.youtube.com/embed/1LPGDq8631o 105 2026-10-09T14:44:01+00:00 yes https://xdme.com/watch-book26-q030.html https://xdme.com/book26-thumbs/page-030.jpg How do gecko feet stick to walls? A gecko's toes are covered with millions of tiny hairs, and each hair splits into even tinier tips. These tips get so close to the wall that weak attractions between molecules add up to a strong grip. The gecko can peel its foot off by changing the angle. Scientists have made gecko-inspired tapes that stick and release many times without glue. https://socialmedia.xdme.com/tony/videos-book26/page-030.mp4 https://www.youtube.com/embed/GThuy8D-ypw 106 2026-10-09T14:44:02+00:00 yes https://xdme.com/watch-book26-q031.html https://xdme.com/book26-thumbs/page-031.jpg How can bumps on a whale's flipper improve wind turbines? Humpback whales have bumps called tubercles along the front edge of their flippers. They look like they would slow the whale down, but they help water flow smoothly so that the flipper keeps working even at steep angles. Engineers added similar bumps to fan and turbine blades. This helps them work better, especially in light or gusty wind. https://socialmedia.xdme.com/tony/videos-book26/page-031.mp4 https://www.youtube.com/embed/H_5jzhgyKKc 107 2026-10-09T14:44:03+00:00 yes https://xdme.com/watch-book26-q032.html https://xdme.com/book26-thumbs/page-032.jpg How have shark-skin ideas been used in swimsuits and hospitals? Shark skin is covered in tiny, ridged scales that reduce drag. Swimsuit makers tried similar textures, and in 2008 many swimmers broke records in new suits. Much of that speed came from tight, water-shedding fabric, and swimming’s governing body banned most of those suits in 2010. Another use is a surface pattern copied from shark skin, called Sharklet, that makes it harder for germs to settle on hospital surfaces. https://socialmedia.xdme.com/tony/videos-book26/page-032.mp4 https://www.youtube.com/embed/Bk966iDKJb4 111 2026-10-09T14:44:05+00:00 yes https://xdme.com/watch-book26-q033.html https://xdme.com/book26-thumbs/page-033.jpg How did an architect copy termite mounds to cool an office building? In Harare, Zimbabwe, the Eastgate Centre office building opened in 1996. Architect Mick Pearce was inspired by termite mounds, which stay steady in temperature while it is hot outside. At night, fans pull cool air through the building and push warm air out through tall chimneys. Thick concrete soaks up heat in the day and releases it later. The building uses far less energy for cooling than normal office towers. https://socialmedia.xdme.com/tony/videos-book26/page-033.mp4 https://www.youtube.com/embed/caMNtXdFZbc 113 2026-10-09T14:44:06+00:00 yes https://xdme.com/watch-book26-q034.html https://xdme.com/book26-thumbs/page-034.jpg How did a boxy fish inspire a car? The boxfish looks like a rectangle with fins, yet it swims easily and has strong, light armor. Designers at a car company built a concept car shaped like a boxfish. It had a roomy interior but slipped through the air with little drag. Engineers also studied the fish's bony plates to learn how to build strong, light shapes. https://socialmedia.xdme.com/tony/videos-book26/page-034.mp4 https://www.youtube.com/embed/anaPND7VoM0 106 2026-10-09T14:44:07+00:00 yes https://xdme.com/watch-book26-q035.html https://xdme.com/book26-thumbs/page-035.jpg How do labs make spider-silk-like fibers without spiders? Spiders cannot be farmed like silkworms, because they attack each other when crowded. So scientists copy the recipe instead. They put spider-silk genes into tiny living things such as bacteria or yeast, which then make silk protein in big tanks. The protein is spun into thread. Companies have made test jackets and ties from it, and doctors hope to use such fibers for strong, gentle stitches. https://socialmedia.xdme.com/tony/videos-book26/page-035.mp4 https://www.youtube.com/embed/VKQjJYJMiV8 109 2026-10-09T14:44:09+00:00 yes https://xdme.com/watch-book26-q036.html https://xdme.com/book26-thumbs/page-036.jpg How did the Titanic disaster lead to sonar? After the Titanic hit an iceberg and sank in 1912, inventors looked for ways to find hidden dangers at sea by sound. In 1914, a Canadian inventor, Reginald Fessenden, built a device that sent out sound pulses and picked up echoes. Off Newfoundland, it detected an iceberg about two miles away. During World War I, other inventors, such as Paul Langevin in France, improved the idea to find submarines. Bats and dolphins use echoes too, but sonar was not copied from them. https://socialmedia.xdme.com/tony/videos-book26/page-036.mp4 https://www.youtube.com/embed/Mnrs_6-Cfi4 117 2026-10-09T14:44:10+00:00 yes https://xdme.com/watch-book26-q037.html https://xdme.com/book26-thumbs/page-037.jpg How does a pitcher plant inspire slippery surfaces? A pitcher plant has a slippery rim, and insects that land on it slide into the plant’s watery pool. Scientists at Harvard studied it around 2011 and made a surface soaked with a thin layer of liquid that stays locked in place. Honey, ketchup, and even oil slide right off. Companies now explore this idea for bottle linings, pipes, and coatings so things do not stick. https://socialmedia.xdme.com/tony/videos-book26/page-037.mp4 https://www.youtube.com/embed/zkc980EqyPk 109 2026-10-09T14:44:11+00:00 yes https://xdme.com/watch-book26-q038.html https://xdme.com/book26-thumbs/page-038.jpg How did a mosquito inspire gentler needles? A mosquito can draw blood so gently that you may not feel it, because its mouthparts are very thin and slide in with tiny jiggling motions. Researchers used this idea to design needles that are as thin as a mosquito's mouthparts. These might make shots and blood tests less painful. Nature's tiny engineers can have big lessons. https://socialmedia.xdme.com/tony/videos-book26/page-038.mp4 https://www.youtube.com/embed/B46KGQIw-Us 107 2026-10-09T14:44:13+00:00 yes https://xdme.com/watch-book26-q039.html https://xdme.com/book26-thumbs/page-039.jpg How did a gliding rainforest seed inspire an early airplane? In the rainforests of Southeast Asia, a vine called Alsomitra grows seeds with big, thin, papery wings that glide gently in a steady line. Around 1907, Austrian engineer Igo Etrich studied the seeds and copied their curved, swept-back wings in his gliders. By 1910, they became the Etrich Taube, an early airplane that was easy to keep stable in the air. A tiny seed helped teach people how wings can balance. https://socialmedia.xdme.com/tony/videos-book26/page-039.mp4 https://www.youtube.com/embed/861KiIeLo_w 113 2026-10-09T14:44:14+00:00 yes https://xdme.com/watch-book26-q040.html https://xdme.com/book26-thumbs/page-040.jpg Why is mother-of-pearl so tough? The shiny inside of a shell, called mother-of-pearl or nacre, is built from tiny flat tiles of a hard mineral stacked like bricks and glued by soft layers. When a crack starts, the layers stop it from spreading. This makes nacre much tougher than the mineral by itself. Scientists are making materials with this brick-and-glue design for strong coatings and armor-like panels. https://socialmedia.xdme.com/tony/videos-book26/page-040.mp4 https://www.youtube.com/embed/BKPcIVMTEf4 109 2026-10-09T14:44:15+00:00 yes https://xdme.com/watch-book26-q041.html https://xdme.com/book26-thumbs/page-041.jpg How does a sandcastle worm glue sand underwater? Sandcastle worms build tubes by gluing together grains of sand and shell pieces. They use a sticky protein that sets even when wet. Most glues don't work underwater, so scientists are studying this natural glue. They hope to make medical adhesives that can help repair broken bones or close wounds inside the body. https://socialmedia.xdme.com/tony/videos-book26/page-041.mp4 https://www.youtube.com/embed/wZrbSA7ZcFQ 109 2026-10-09T14:44:17+00:00 yes https://xdme.com/watch-book26-q042.html https://xdme.com/book26-thumbs/page-042.jpg Why are honeycomb patterns used in strong, light panels? Engineers make panels by putting a honeycomb of thin material between two thin sheets, like a sandwich. The sheets resist stretching and squashing, and the honeycomb keeps them apart so the panel does not bend easily. Most of the panel is air, so it is very light. You can find these panels in airplane floors, doors, surfboards, and cardboard boxes. They are strong for their weight. https://socialmedia.xdme.com/tony/videos-book26/page-042.mp4 https://www.youtube.com/embed/noJWKZ-xFu4 108 2026-10-09T14:44:18+00:00 yes https://xdme.com/watch-book26-q043.html https://xdme.com/book26-thumbs/page-043.jpg Why is bamboo such a strong plant? Bamboo is a hollow tube with solid rings called nodes along its length. The tube shape is stiff for its weight, and the nodes act like bands that keep it from bending too much. Bamboo grows very fast and is used for scaffolding, furniture, and even bike frames. Designers study its structure to build lighter, tougher poles and towers. https://socialmedia.xdme.com/tony/videos-book26/page-043.mp4 https://www.youtube.com/embed/bTJjW8M9-sA 105 2026-10-09T14:44:20+00:00 yes https://xdme.com/watch-book26-q044.html https://xdme.com/book26-thumbs/page-044.jpg Could a chameleon's color-changing skin become a new kind of material? Chameleon skin has layers of tiny crystals. When the chameleon relaxes or tightens its skin, the spacing between the crystals changes, and they reflect different colors of light. Scientists copied the idea to make stretchy films that change color when they are pulled. Someday this kind of material could be used as color-changing sensors, safety labels, or clothing that adapts to its surroundings. https://socialmedia.xdme.com/tony/videos-book26/page-044.mp4 https://www.youtube.com/embed/vn06qEevbZQ 113 2026-10-09T14:44:22+00:00 yes https://xdme.com/watch-book26-q045.html https://xdme.com/book26-thumbs/page-045.jpg How did fireflies make LED lights brighter? Scientists studied the glowing part of a firefly's body and found that it is covered with tiny, jagged scales. These let more light escape instead of being trapped inside. When they gave the surface of LEDs a similar shape, the lights became brighter without extra energy. A small bug turned out to be a lighting expert. https://socialmedia.xdme.com/tony/videos-book26/page-045.mp4 https://www.youtube.com/embed/lvip5sIF-64 111 2026-10-09T14:44:23+00:00 yes https://xdme.com/watch-book26-q046.html https://xdme.com/book26-thumbs/page-046.jpg How do moth eyes help screens and solar panels? A moth's eye is covered with a pattern of tiny bumps that reduces shine, so light goes in rather than bouncing off. This helps the moth hide from predators at night. Engineers copy this by putting very tiny bumps on glass and plastic. This makes anti-glare screens and helps solar panels absorb more sunlight. https://socialmedia.xdme.com/tony/videos-book26/page-046.mp4 https://www.youtube.com/embed/jW0E5_G9xfA 105 2026-10-09T14:44:24+00:00 yes https://xdme.com/watch-book26-q047.html https://xdme.com/book26-thumbs/page-047.jpg How do engineers look for nature's answers to a problem? A biomimicry designer starts with a question, like how to keep a building cool, and asks, how does nature do it? They search for living things that face the same challenge, study how they solve it, and then turn the idea into a design. There are online libraries of nature's solutions. Then they build and test, since an idea has to work in the real world. https://socialmedia.xdme.com/tony/videos-book26/page-047.mp4 https://www.youtube.com/embed/Q1ie2BSp6j0 104 2026-10-09T14:44:25+00:00 yes https://xdme.com/watch-book26-q048.html https://xdme.com/book26-thumbs/page-048.jpg Does nature always have the best design? Nature's designs are clever, but they are not always perfect. Living things have to be good enough to survive, and they are made from the materials and building steps available to them. People have different needs, like wheels, which hardly ever appear in nature. Engineers borrow the best ideas and mix them with their own to create new ones. https://socialmedia.xdme.com/tony/videos-book26/page-048.mp4 https://www.youtube.com/embed/-KXh2Edj3E0 106 2026-10-09T14:44:26+00:00 yes https://xdme.com/watch-book26-q049.html https://xdme.com/book26-thumbs/page-049.jpg How can you be a biomimicry detective at home? Go outside with a notebook and look closely at plants, bugs, birds, and rocks. Ask what each feature might do. Why is a pinecone scaled? Why do leaves have veins? Then ask what problem it could help solve. Draw your ideas and try a model. Many inventors started with simple questions. https://socialmedia.xdme.com/tony/videos-book26/page-049.mp4 https://www.youtube.com/embed/8cadindvIv8 106 2026-10-09T14:44:27+00:00 yes https://xdme.com/watch-book26-q050.html https://xdme.com/book26-thumbs/page-050.jpg How did a cat's tongue inspire a better hairbrush? A cat's tongue is rough because it has tiny hooked spines. They are shaped like little scoops and help the cat clean and groom its fur. Scientists used a microscope and a 3D printer to copy these spines. They designed a brush that cleans itself, because tangles slide off the barbs. Even something as small as a tongue can inspire an invention. https://socialmedia.xdme.com/tony/videos-book26/page-050.mp4 https://www.youtube.com/embed/sorPtBESdzs 106 2026-10-09T14:44:29+00:00 yes https://xdme.com/watch-book26-q051.html https://xdme.com/book26-thumbs/page-051.jpg Who invented the wheel, and why was it such a big deal? Nobody knows who invented the wheel. Wheels were used in Mesopotamia and in Europe about 5,500 years ago, for pottery and soon after for carts. The oldest wheel found so far, from Slovenia, is about 5,150 years old. Before that, people used sleds and log rollers. A wheel that turns on a fixed axle must be round and fit snugly, which is hard to make. It changed travel and farming forever. https://socialmedia.xdme.com/tony/videos-book26/page-051.mp4 https://www.youtube.com/embed/dOXIbpmcN_c 113 2026-10-09T14:44:30+00:00 yes https://xdme.com/watch-book26-q052.html https://xdme.com/book26-thumbs/page-052.jpg Why is a pencil's "lead" not really lead? Pencil cores are made of graphite, a soft, slippery form of carbon. In the 1500s, people in England found a big deposit of it and thought it was a kind of lead because it left gray marks. The name stuck. In 1795, a French inventor mixed graphite with clay and baked it, which lets makers control how hard or soft the pencil is. https://socialmedia.xdme.com/tony/videos-book26/page-052.mp4 https://www.youtube.com/embed/B5XEEcuVRH0 107 2026-10-09T14:44:32+00:00 yes https://xdme.com/watch-book26-q053.html https://xdme.com/book26-thumbs/page-053.jpg How does an eraser erase? Before rubber erasers, people used bread crumbs to rub away pencil marks. In the 1770s, a scientist discovered that a piece of natural rubber could do the job better, and the word rubber was born. An eraser works by being stickier to graphite than the paper is. As you rub, tiny graphite bits cling to the eraser and the crumbs carry them away. https://socialmedia.xdme.com/tony/videos-book26/page-053.mp4 https://www.youtube.com/embed/s8n6ad0nCjc 106 2026-10-09T14:44:33+00:00 yes https://xdme.com/watch-book26-q054.html https://xdme.com/book26-thumbs/page-054.jpg How does a ballpoint pen work? At the tip of a ballpoint pen is a tiny metal ball in a socket. As you write, the ball rolls and picks up thick ink from inside, laying it on the paper. In the 1930s, Hungarian journalist László Bíró noticed that newspaper ink dried fast and thought it would work better than runny fountain-pen ink if a ball could carry it. https://socialmedia.xdme.com/tony/videos-book26/page-054.mp4 https://www.youtube.com/embed/cCbtPMRe1EU 102 2026-10-09T14:44:34+00:00 yes https://xdme.com/watch-book26-q055.html https://xdme.com/book26-thumbs/page-055.jpg How was paper first made in ancient China? Paper was made in China around 2,000 years ago. An official named Cai Lun is traditionally credited with improving it using plant fibers, old rags, and bark. The fibers were beaten into pulp, spread on a screen, and dried into sheets. Before this, people wrote on clay, bamboo, silk, or papyrus. Paper-making spread along trade routes across the world. https://socialmedia.xdme.com/tony/videos-book26/page-055.mp4 https://www.youtube.com/embed/w45ll7zePcE 107 2026-10-09T14:44:36+00:00 yes https://xdme.com/watch-book26-q056.html https://xdme.com/book26-thumbs/page-056.jpg When were eyeglasses invented? The first eyeglasses were made in Italy around 1286. They used curved pieces of glass or crystal that magnified words for people whose near vision was getting blurry. At first, people held them in front of their eyes or balanced them on the nose. Later, makers added frames that hooked over the ears. Eyeglasses helped many people keep reading. https://socialmedia.xdme.com/tony/videos-book26/page-056.mp4 https://www.youtube.com/embed/5BV3VNCPPb4 111 2026-10-09T14:44:36+00:00 yes https://xdme.com/watch-book26-q057.html https://xdme.com/book26-thumbs/page-057.jpg When was the umbrella invented? Umbrellas are thousands of years old. In ancient China and Egypt, people held them over their heads to make shade from the Sun. Later, people covered them with oiled paper or silk so they would also keep off rain. The word comes from a Latin word meaning shade. Folding umbrellas with metal ribs came later. https://socialmedia.xdme.com/tony/videos-book26/page-057.mp4 https://www.youtube.com/embed/bVjozcqH7Hg 102 2026-10-09T14:44:37+00:00 yes https://xdme.com/watch-book26-q058.html https://xdme.com/book26-thumbs/page-058.jpg How did people clean their teeth before toothbrushes? Long ago, people chewed on twigs with frayed ends to rub their teeth clean. In China around 1498, someone made a brush with animal bristles on a bone handle. Brushes slowly spread, and nylon bristles replaced animal hair in 1938. Today, toothbrushes are soft, small, and comfortable. Brushing twice a day for two minutes keeps teeth healthy. https://socialmedia.xdme.com/tony/videos-book26/page-058.mp4 https://www.youtube.com/embed/nDcwPfGpTAk 111 2026-10-09T14:44:38+00:00 yes https://xdme.com/watch-book26-q059.html https://xdme.com/book26-thumbs/page-059.jpg How did people keep food cold before refrigerators? In cold places, workers cut big blocks of ice from frozen lakes in winter and stored them in sheds packed with sawdust. In summer the ice was delivered to homes and put into insulated iceboxes. Machines that move heat out of a box, the way modern fridges do, appeared in the 1800s. Electric home refrigerators became common in the 1930s. https://socialmedia.xdme.com/tony/videos-book26/page-059.mp4 https://www.youtube.com/embed/qbtVxuwxbeA 109 2026-10-09T14:44:39+00:00 yes https://xdme.com/watch-book26-q060.html https://xdme.com/book26-thumbs/page-060.jpg How does a tin can keep food fresh for years? In the early 1800s, a French confectioner named Nicolas Appert found that food sealed in jars and heated stayed good for a long time. Soon after, a British inventor made tin-coated steel cans. Heating kills the germs that make food spoil, and the sealed can keeps new germs out. The can opener was not invented until about 50 years later, so people used hammers and chisels. https://socialmedia.xdme.com/tony/videos-book26/page-060.mp4 https://www.youtube.com/embed/e6ImuiRE2y0 111 2026-10-09T14:44:40+00:00 yes https://xdme.com/watch-book26-q061.html https://xdme.com/book26-thumbs/page-061.jpg Why does a paper clip hold papers together? A paper clip is a piece of bent wire in a loop within a loop. When you slide it over paper, the wire bends slightly apart and then springs back, squeezing the sheets. The metal is springy but not too stiff. The common Gem-style clip, with two loops, was made around the 1890s. It is a simple machine that uses spring force. https://socialmedia.xdme.com/tony/videos-book26/page-061.mp4 https://www.youtube.com/embed/MemdudqPP4s 105 2026-10-09T14:44:41+00:00 yes https://xdme.com/watch-book26-q062.html https://xdme.com/book26-thumbs/page-062.jpg How was the safety pin invented? In 1849, American inventor Walter Hunt owed money and needed a quick idea. He picked up a piece of brass wire and began twisting it. In about three hours, he had made a pin with a coil spring at one end and a cover to hold the sharp point safely. He sold the idea for a few hundred dollars. Safety pins are still used all over the world. https://socialmedia.xdme.com/tony/videos-book26/page-062.mp4 https://www.youtube.com/embed/fSmdYpkCgT8 104 2026-10-09T14:44:43+00:00 yes https://xdme.com/watch-book26-q063.html https://xdme.com/book26-thumbs/page-063.jpg How did the bicycle change over time? The first bike-like machine, around 1817, had no pedals, and riders pushed with their feet. Later, pedals were attached to the front wheel. In the 1870s, the penny-farthing had a giant front wheel to go faster. The modern bike with two same-sized wheels and a chain appeared in the 1880s and is called the safety bicycle. Bikes keep improving. https://socialmedia.xdme.com/tony/videos-book26/page-063.mp4 https://www.youtube.com/embed/fTV6lCBm0jg 109 2026-10-09T14:44:44+00:00 yes https://xdme.com/watch-book26-q064.html https://xdme.com/book26-thumbs/page-064.jpg Who invented the flashlight? The flashlight became possible after small batteries and bulbs were invented in the 1890s. The first ones were called electric hand torches. They were often cardboard tubes with a small bulb and short-lived batteries. They made only short flashes, which is where the name flashlight came from. Today, LEDs and better batteries make flashlights bright and long-lasting. https://socialmedia.xdme.com/tony/videos-book26/page-064.mp4 https://www.youtube.com/embed/wGfZ5itsZGg 111 2026-10-09T14:44:44+00:00 yes https://xdme.com/watch-book26-q065.html https://xdme.com/book26-thumbs/page-065.jpg Who invented the telephone? Alexander Graham Bell is credited with inventing the telephone in 1876. Bell was born in Scotland and taught deaf students, and his experiments with sound led to the invention. His family moved to Brantford, Ontario, where he worked on ideas. On August 10, 1876, a call between Brantford and Paris, Ontario, eight miles away, was one of the first long-distance calls. https://socialmedia.xdme.com/tony/videos-book26/page-065.mp4 https://www.youtube.com/embed/jULSRJ8DSUI 112 2026-10-09T14:44:46+00:00 yes https://xdme.com/watch-book26-q066.html https://xdme.com/book26-thumbs/page-066.jpg How did the first phonograph record sound? In 1877, Thomas Edison invented the phonograph, a machine that could record and play back sound. A person spoke into a horn, and the sound waves made a needle wiggle against a sheet of tinfoil on a rotating cylinder, leaving tiny dents. Dragging the needle through the dents again made the sound play back. Edison's first recording was a nursery rhyme. https://socialmedia.xdme.com/tony/videos-book26/page-066.mp4 https://www.youtube.com/embed/u9KDTlfGbqE 107 2026-10-09T14:44:47+00:00 yes https://xdme.com/watch-book26-q067.html https://xdme.com/book26-thumbs/page-067.jpg How did the thermometer develop? Around 1600, Galileo built a device that showed changes in temperature but had no scale. Daniel Fahrenheit made a mercury thermometer with a scale in 1714. In 1742, Anders Celsius made a scale based on the freezing and boiling of water. Canada uses Celsius, and the United States uses Fahrenheit. Today thermometers use liquid, metal strips, or electronic sensors. https://socialmedia.xdme.com/tony/videos-book26/page-067.mp4 https://www.youtube.com/embed/6JTsB1qCQuY 118 2026-10-09T14:44:48+00:00 yes https://xdme.com/watch-book26-q068.html https://xdme.com/book26-thumbs/page-068.jpg How does a key open a lock? Inside most locks is a row of small pins of different lengths. A key has bumps and cuts that push each pin to just the right height so they line up along a line. Then the lock's cylinder can turn. The wrong key leaves some pins in the way. Pin locks were first made in Egypt, and Linus Yale Jr. improved the design in the 1860s. https://socialmedia.xdme.com/tony/videos-book26/page-068.mp4 https://www.youtube.com/embed/lQoYv7B1LGY 102 2026-10-09T14:44:49+00:00 yes https://xdme.com/watch-book26-q069.html https://xdme.com/book26-thumbs/page-069.jpg Who invented the goalie mask? Goalies used to play without any face protection. In 1959, Montreal goalie Jacques Plante was hit by a puck in the face. He insisted on wearing a mask he had made of fiberglass. His coach wasn't sure, but Plante kept wearing it, and other goalies soon followed. Today, masks are made of strong, light materials. Safety inventions often start with a problem. https://socialmedia.xdme.com/tony/videos-book26/page-069.mp4 https://www.youtube.com/embed/AXcbwjFyrQQ 110 2026-10-09T14:51:22+00:00 yes https://xdme.com/watch-book26-q070.html https://xdme.com/book26-thumbs/page-070.jpg Who invented the snowmobile? Joseph-Armand Bombardier of Quebec loved engines. As a teenager in 1922, he built a propeller-driven sled. In 1934, his young son became ill when deep snow kept the family from reaching a hospital, and Bombardier decided to build a vehicle that could travel on snow. His 1937 snow vehicle had tracks and a cabin that carried seven people. In 1959, he introduced the small Ski-Doo for fun. https://socialmedia.xdme.com/tony/videos-book26/page-070.mp4 https://www.youtube.com/embed/2nF8L31_0eE 113 2026-10-09T14:51:23+00:00 yes https://xdme.com/watch-book26-q071.html https://xdme.com/book26-thumbs/page-071.jpg Who invented basketball? In 1891, a Canadian teacher named James Naismith was asked to invent an indoor game for students in Massachusetts during winter. He nailed two peach baskets up high on walls and wrote 13 rules. The ball had to be thrown into the basket, not carried. The bottoms of the baskets were closed at first, so someone had to climb a ladder to get the ball out. https://socialmedia.xdme.com/tony/videos-book26/page-071.mp4 https://www.youtube.com/embed/xnAZQ7Wy3jo 108 2026-10-09T14:51:24+00:00 yes https://xdme.com/watch-book26-q072.html https://xdme.com/book26-thumbs/page-072.jpg What makes LEGO bricks fit together so well? LEGO bricks have studs on top and tubes underneath that squeeze together tightly. The bricks are made very precisely, within a tiny fraction of a millimeter. A Danish carpenter, Ole Kirk Christiansen, started making wooden toys in the 1930s and then changed to plastic. His company's stud-and-tube design from 1958 still fits with new bricks today. https://socialmedia.xdme.com/tony/videos-book26/page-072.mp4 https://www.youtube.com/embed/26slUpcSxhE 112 2026-10-09T14:51:25+00:00 yes https://xdme.com/watch-book26-q073.html https://xdme.com/book26-thumbs/page-073.jpg Why are phone keypads and calculators laid out in opposite orders? On most phones, 1-2-3 are on the top row, but on calculators and computer number pads, 7-8-9 are on top. In the early 1960s, researchers tested layouts and chose the one that people could dial quickly. Calculators copied the layout of old adding machines. Both layouts work, and people learn whichever one they use often. Old habits can be hard to change. https://socialmedia.xdme.com/tony/videos-book26/page-073.mp4 https://www.youtube.com/embed/CbvWsvSI4-8 111 2026-10-09T14:51:26+00:00 yes https://xdme.com/watch-book26-q074.html https://xdme.com/book26-thumbs/page-074.jpg Who invented the Ferris wheel? George Ferris, an engineer, built the first giant Ferris wheel for the 1893 World's Fair in Chicago. Organizers wanted something to rival the Eiffel Tower. The wheel was 264 feet high, and it had 36 cars, each holding up to 60 people. It was held by a massive steel axle. Many modern observation wheels follow the same idea. https://socialmedia.xdme.com/tony/videos-book26/page-074.mp4 https://www.youtube.com/embed/2YhH0OuHvp0 111 2026-10-09T14:51:27+00:00 yes https://xdme.com/watch-book26-q075.html https://xdme.com/book26-thumbs/page-075.jpg Does one person usually invent something alone? Most inventions grow from many people's ideas. Before Thomas Edison made his light bulb, other inventors had made glowing lamps, and later workers improved Edison's. Several people also worked on the telephone at the same time. Inventors build on earlier ideas, test, and improve them. Credit often goes to one name, but there are many people behind the story. https://socialmedia.xdme.com/tony/videos-book26/page-075.mp4 https://www.youtube.com/embed/HL3IBaFVdaU 112 2026-10-09T14:51:28+00:00 yes https://xdme.com/watch-book26-q076.html https://xdme.com/book26-thumbs/page-076.jpg How did an 11-year-old invent the Popsicle? In 1905, eleven-year-old Frank Epperson of San Francisco mixed soda powder and water with a stick and accidentally left the cup outside on a cold night. By morning, the drink had frozen around the stick. He had made the first frozen treat on a stick. Years later, he sold the idea and called it the Epsicle, which became the Popsicle. https://socialmedia.xdme.com/tony/videos-book26/page-076.mp4 https://www.youtube.com/embed/cCm06ZT22Mo 107 2026-10-09T14:51:29+00:00 yes https://xdme.com/watch-book26-q077.html https://xdme.com/book26-thumbs/page-077.jpg Who invented earmuffs when he was a teenager? In 1873, fifteen-year-old Chester Greenwood of Maine was out ice skating when his ears got very cold. He asked his grandmother to sew fur onto bent wire loops that fit over his ears. Friends wanted them too. Chester later got a patent and started a factory. Maine still celebrates a day in his honor each December. https://socialmedia.xdme.com/tony/videos-book26/page-077.mp4 https://www.youtube.com/embed/J_TGEEsHXMA 109 2026-10-09T14:51:30+00:00 yes https://xdme.com/watch-book26-q078.html https://xdme.com/book26-thumbs/page-078.jpg How did a teenager invent a reading system for blind people? Louis Braille lost his sight as a young child in France. At fifteen, in 1824, he created a system of raised dots that people could read with their fingertips. He built on an army code called night writing. His version used six dots in a small cell, and different patterns stood for letters, numbers, and music. Braille is used all over the world today. https://socialmedia.xdme.com/tony/videos-book26/page-078.mp4 https://www.youtube.com/embed/6TRY8Q_KAnU 111 2026-10-09T14:51:31+00:00 yes https://xdme.com/watch-book26-q079.html https://xdme.com/book26-thumbs/page-079.jpg What did a boy farmer's field have to do with television? In 1921, fourteen-year-old Philo Farnsworth was plowing rows in a potato field in Idaho when he thought that a picture might be scanned line by line, like the rows of a field. He sketched his idea for a teacher. In 1927, at age twenty-one, he made the first electronic television picture. Scanning in lines is still how screens build pictures. https://socialmedia.xdme.com/tony/videos-book26/page-079.mp4 https://www.youtube.com/embed/x148h-VtXEE 110 2026-10-09T14:51:32+00:00 yes https://xdme.com/watch-book26-q080.html https://xdme.com/book26-thumbs/page-080.jpg How did a boy in Kenya keep lions away from his family's cattle? Richard Turere lived near a national park in Kenya. At night, lions came near his family's animals. He noticed that the big cats didn't come near when someone walked with a flashlight. At around age eleven, he built a system of flashing lights wired to a solar panel and car battery. The "lion lights" worked, and people copied them. They help both animals and people stay safe. https://socialmedia.xdme.com/tony/videos-book26/page-080.mp4 https://www.youtube.com/embed/mP7FFn-Agrw 112 2026-10-09T14:51:34+00:00 yes https://xdme.com/watch-book26-q081.html https://xdme.com/book26-thumbs/page-081.jpg How did a teenager invent a flashlight that needs no batteries? Ann Makosinski, from British Columbia, was fifteen when she built the Hollow Flashlight. It uses small thermoelectric tiles that turn the difference between the warmth of your hand and cool air into a tiny bit of electricity. That electricity powers an LED. She won an award at the Google Science Fair in 2013. Her idea shows how heat can be turned into power. https://socialmedia.xdme.com/tony/videos-book26/page-081.mp4 https://www.youtube.com/embed/XQg82RfFPRQ 111 2026-10-09T14:51:34+00:00 yes https://xdme.com/watch-book26-q082.html https://xdme.com/book26-thumbs/page-082.jpg How did a 14-year-old build a robotic hand from simple parts? Easton LaChappelle of Colorado was fourteen when he made a robotic hand out of LEGO pieces, fishing line, and electrical tape, so he could learn how it worked. At a science fair, he met a young girl who used a very expensive prosthetic arm. He decided to design a cheaper one. His low-cost arm used 3D printing and motors to move fingers. https://socialmedia.xdme.com/tony/videos-book26/page-082.mp4 https://www.youtube.com/embed/uAbcGNk4C-U 109 2026-10-09T14:51:35+00:00 yes https://xdme.com/watch-book26-q083.html https://xdme.com/book26-thumbs/page-083.jpg How did an eleven-year-old design a way to find lead in water? Gitanjali Rao from Colorado was eleven when she read about lead in drinking water in a city in Michigan. She designed a device called Tethys, which uses special sensors to detect lead in water quickly. In 2020, TIME magazine named her the first Kid of the Year. She says that anyone can solve problems if they look closely and keep trying. https://socialmedia.xdme.com/tony/videos-book26/page-083.mp4 https://www.youtube.com/embed/XjThnCRyQic 109 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book26-q084.html https://xdme.com/book26-thumbs/page-084.jpg Why are kids often good at inventing? Kids ask lots of questions, notice small problems, and don't yet know what "can't be done." Looking at things with fresh eyes can lead to new ideas. Many kid inventors began by solving something that bothered them, such as cold ears or reading in the dark. Adults can help by finding materials and testing for safety, but the original idea often comes from curiosity. https://socialmedia.xdme.com/tony/videos-book26/page-084.mp4 https://www.youtube.com/embed/wEZtJv4M9Z8 106 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book26-q085.html https://xdme.com/book26-thumbs/page-085.jpg Where can a young inventor share and test an idea? Many schools, libraries, and museums run science fairs and invention contests where kids show their ideas to judges and the public. In Canada, regional science fairs can lead to the national Canada-Wide Science Fair. Some contests have categories for different ages, and some let teams work together. Even if you don't win, you get feedback, meet other makers, and improve your invention. https://socialmedia.xdme.com/tony/videos-book26/page-085.mp4 https://www.youtube.com/embed/0rWNaq76xUw 109 2026-10-09T14:51:39+00:00 yes https://xdme.com/watch-book26-q086.html https://xdme.com/book26-thumbs/page-086.jpg How does the Zamboni make hockey ice smooth? Frank Zamboni, who ran an ice rink in California, invented the machine in 1949. It scrapes a thin layer off the top of the ice, collects the shavings, washes the surface, and then spreads a thin film of warm water that freezes into a fresh smooth sheet. Rinks need this because skates carve rough lines in the ice. Many skaters like watching it work. https://socialmedia.xdme.com/tony/videos-book26/page-086.mp4 https://www.youtube.com/embed/Nl05GDgWAjw 108 2026-10-09T14:54:40+00:00 yes https://xdme.com/watch-book26-q087.html https://xdme.com/book26-thumbs/page-087.jpg How did a water experiment lead to the Super Soaker? Lonnie Johnson was an engineer who worked on space missions. In 1982, he was testing a cooling system idea at home when a nozzle on his sink-top experiment shot a powerful stream of water across the bathroom. He thought it would make a great toy. After years of trying to sell it, the Super Soaker became a hit in 1990 and one of the best-selling water toys. https://socialmedia.xdme.com/tony/videos-book26/page-087.mp4 https://www.youtube.com/embed/1RuMIFuqZYU 107 2026-10-09T14:55:17+00:00 yes https://xdme.com/watch-book26-q088.html https://xdme.com/book26-thumbs/page-088.jpg Why did Betamax lose to VHS? In the 1970s, two video tape formats competed. Sony's Betamax had good picture quality, but its tapes held only about one hour at first. VHS tapes were bigger and could record longer shows and whole movies. More companies also made VHS machines, so stores stocked more tapes. People chose the format that was more convenient, and VHS won. https://socialmedia.xdme.com/tony/videos-book26/page-088.mp4 https://www.youtube.com/embed/9-IWzgD4NVk 111 2026-10-09T14:55:18+00:00 yes https://xdme.com/watch-book26-q089.html https://xdme.com/book26-thumbs/page-089.jpg Why did the Ford Edsel car fail? In 1957, Ford launched a new car called the Edsel after years of planning and big advertising. But the car sold far fewer than the company hoped. It had a strange front grill that many people did not like, the price was confusing, and some early cars had flaws. Tastes changed, and Ford stopped making Edsels in 1959. The name still means a big flop. https://socialmedia.xdme.com/tony/videos-book26/page-089.mp4 https://www.youtube.com/embed/q3jQ8Ao9F0M 109 2026-10-09T14:55:18+00:00 yes https://xdme.com/watch-book26-q090.html https://xdme.com/book26-thumbs/page-090.jpg What happened to the Segway? In 2001, inventor Dean Kamen unveiled the Segway, a two-wheeled, self-balancing scooter that stays upright with gyroscopes and sensors. People expected it to change how cities move. But it cost thousands of dollars, and many places didn't allow it on sidewalks or roads. It became popular for tours and security patrols. Production of the original model ended in 2020. https://socialmedia.xdme.com/tony/videos-book26/page-090.mp4 https://www.youtube.com/embed/qX2yUfOYcwk 112 2026-10-09T14:55:19+00:00 yes https://xdme.com/watch-book26-q091.html https://xdme.com/book26-thumbs/page-091.jpg Why did early parachutes swing wildly, and how did a vent hole help? The first parachutes were big, closed umbrellas of cloth. When André-Jacques Garnerin jumped from a balloon over Paris in 1797, his parachute swung back and forth so hard that he felt sick. Air kept spilling out from the edges first on one side, and then the other. A French astronomer, Joseph Lalande, suggested a hole at the top. Air escapes smoothly through it, so the parachute steadies. https://socialmedia.xdme.com/tony/videos-book26/page-091.mp4 https://www.youtube.com/embed/zhiSTcIkblg 111 2026-10-09T14:55:21+00:00 yes https://xdme.com/watch-book26-q092.html https://xdme.com/book26-thumbs/page-092.jpg Why do engineers study things that go wrong? When something breaks or fails, engineers look for the cause so they can prevent it next time. In 1940, a long bridge in Washington State twisted and shook in the wind, which led to its collapse. No people were hurt. Engineers studied it and learned about wind and vibration. Today, bridges are tested in wind tunnels. Safe designs often come from learning from mistakes. https://socialmedia.xdme.com/tony/videos-book26/page-092.mp4 https://www.youtube.com/embed/uGRdVgtVaNk 111 2026-10-09T14:55:22+00:00 yes https://xdme.com/watch-book26-q093.html https://xdme.com/book26-thumbs/page-093.jpg Why don't we all have jetpacks? In the 1960s, an American team built a rocket belt that could lift one person into the air. But it only flew for about 30 seconds and needed special fuel, a lot of noise, and a trained pilot. Newer jetpacks can fly longer but are costly, loud, and risky. Water-jet packs that push a rider up from the surface are fun, but they need to be near water. https://socialmedia.xdme.com/tony/videos-book26/page-093.mp4 https://www.youtube.com/embed/IK7opUhhT8k 105 2026-10-09T14:55:23+00:00 yes https://xdme.com/watch-book26-q094.html https://xdme.com/book26-thumbs/page-094.jpg Why did early electric cars lose to gasoline cars? About 1900, many cars were electric. They were quiet, clean, and easy to start. But batteries were heavy and did not take cars very far, and few places had electricity to charge them. Gasoline cars could go farther, fill up fast, and the Ford Model T made them cheaper. In 1912, the electric starter ended the hard crank for gasoline cars. Today better batteries are bringing electric cars back. https://socialmedia.xdme.com/tony/videos-book26/page-094.mp4 https://www.youtube.com/embed/TOWU21uUelU 111 2026-10-09T14:55:24+00:00 yes https://xdme.com/watch-book26-q095.html https://xdme.com/book26-thumbs/page-095.jpg Why did eight-track tapes disappear? In the 1960s and 1970s, eight-track tapes played music in cars. The tape looped inside a big cartridge. But the tapes were bulky, the sound could change between tracks, and songs sometimes broke in the middle. Cassette tapes were smaller and could record, so they took over. Later, CDs and digital music replaced cassettes. Technology often improves in small steps. https://socialmedia.xdme.com/tony/videos-book26/page-095.mp4 https://www.youtube.com/embed/DsqGFiEgPkU 112 2026-10-09T14:55:24+00:00 yes https://xdme.com/watch-book26-q096.html https://xdme.com/book26-thumbs/page-096.jpg Why did floppy disks go away? Floppy disks were once used to save and move files on computers. A common one held only 1.44 megabytes, which is smaller than one photo from a modern phone. As files got bigger, floppy disks could not keep up. USB drives, memory cards, and cloud storage hold far more and are faster. The "save" icon in many programs still looks like a floppy disk. https://socialmedia.xdme.com/tony/videos-book26/page-096.mp4 https://www.youtube.com/embed/DY-pGXMT4X8 109 2026-10-09T14:55:25+00:00 yes https://xdme.com/watch-book26-q097.html https://xdme.com/book26-thumbs/page-097.jpg Which inventions did people once say would never work? Many great ideas were doubted at first. Some people said that machines heavier than air could never fly, until the Wright brothers' first flight in 1903 lasted twelve seconds. Others thought telephones were just toys. New ideas can seem strange, and it takes tests and time to prove them. Good inventors listen to criticism, improve their ideas, and keep trying. https://socialmedia.xdme.com/tony/videos-book26/page-097.mp4 https://www.youtube.com/embed/tjxotRRHTOM 108 2026-10-09T14:55:26+00:00 yes https://xdme.com/watch-book26-q098.html https://xdme.com/book26-thumbs/page-098.jpg What makes one invention succeed and another fail? Successful inventions usually solve a real problem, are easy to use, cost a fair price, and arrive at the right time. Many good ideas fail because they are too expensive, too complicated, or too early for the technology to support them. Sometimes a rival product is simply more convenient. Testing with real users helps inventors find these problems before launching. https://socialmedia.xdme.com/tony/videos-book26/page-098.mp4 https://www.youtube.com/embed/DUDZjpv-dDo 107 2026-10-09T14:55:27+00:00 yes https://xdme.com/watch-book26-q099.html https://xdme.com/book26-thumbs/page-099.jpg What is a Rube Goldberg machine? Rube Goldberg was an American cartoonist who drew funny contraptions where many steps do a simple job, like a ball rolling down a ramp to tip a bucket to pull a string to turn a page. Today, students build real versions as chain reactions. Each step moves energy to the next, and everything must be timed right. They are silly, but they teach planning and problem solving. https://socialmedia.xdme.com/tony/videos-book26/page-099.mp4 https://www.youtube.com/embed/huD5wfkbIss 104 2026-10-09T14:55:29+00:00 yes https://xdme.com/watch-book26-q100.html https://xdme.com/book26-thumbs/page-100.jpg What good can come from an invention that doesn't work? Even invention flops can leave behind good things. They show what customers do not want, expose weak parts, and give new ideas to the next inventor. Some failed products have been rebuilt years later when technology improved. Learning why something failed saves time and money. That is why many inventors keep a record of mistakes along with successes. https://socialmedia.xdme.com/tony/videos-book26/page-100.mp4 https://www.youtube.com/embed/42o7RbU5NNc 103 2026-10-09T14:55:30+00:00 yes https://xdme.com/watch-book26-q101.html https://xdme.com/book26-thumbs/page-101.jpg What is a control, and why does a test need one? A control is a part of a test where you change nothing, so you have something to compare. Say you think music helps you remember words. You read a list in silence first, which is your control. Then you read a different list of the same length while music plays. Without the control, you would not know if the music did anything. A control makes the answer trustworthy. https://socialmedia.xdme.com/tony/videos-book26/page-101.mp4 https://www.youtube.com/embed/lMvIXjqJo40 110 2026-10-09T14:55:31+00:00 yes https://xdme.com/watch-book26-q102.html https://xdme.com/book26-thumbs/page-102.jpg Why do inventors use rulers and timers instead of eyeballing a test? Guessing can be fooled by what you hope to see. Measuring gives numbers that everyone can check. A timer, ruler, or scale shows how fast, long, or heavy something is. Measuring the same thing several times and finding the average makes results more trustworthy. Numbers also show whether version two is truly better than version one, and by how much. https://socialmedia.xdme.com/tony/videos-book26/page-102.mp4 https://www.youtube.com/embed/0Xll-bJgvYQ 106 2026-10-09T14:55:31+00:00 yes https://xdme.com/watch-book26-q103.html https://xdme.com/book26-thumbs/page-103.jpg What is a patent, and why do inventors get one? A patent is a legal document that says a new invention belongs to its inventor. Others cannot make or sell it without permission for about twenty years. In return, the inventor explains in detail how the invention works. This lets inventors earn money from their work and lets everyone learn from the ideas. In Canada, a government office reviews patent applications. https://socialmedia.xdme.com/tony/videos-book26/page-103.mp4 https://www.youtube.com/embed/Vtc6ANZv-Es 105 2026-10-09T14:55:32+00:00 yes https://xdme.com/watch-book26-q104.html https://xdme.com/book26-thumbs/page-104.jpg What's the difference between a patent, a trademark, and a copyright? They protect different things. A patent protects how an invention works. A trademark protects a name, logo, or slogan that tells customers who made something. Copyright protects creative work such as books, songs, drawings, and software code, as soon as it is created. All three give owners a way to control copies, but each has its own rules and time limits. https://socialmedia.xdme.com/tony/videos-book26/page-104.mp4 https://www.youtube.com/embed/ZgS6tEQVpW4 112 2026-10-09T14:55:33+00:00 yes https://xdme.com/watch-book26-q105.html https://xdme.com/book26-thumbs/page-105.jpg How do crash test dummies help make cars safer? Crash test dummies are human-shaped models filled with sensors. In a lab, a car is driven into a wall while high-speed cameras record. The sensors measure how hard the head, chest, and legs would be pushed. Engineers use the data to improve seat belts, airbags, and the car's frame. There are dummies in many sizes, including children's, to help protect everyone. https://socialmedia.xdme.com/tony/videos-book26/page-105.mp4 https://www.youtube.com/embed/I-Ry_MJF-vs 112 2026-10-09T14:55:34+00:00 yes https://xdme.com/watch-book26-q106.html https://xdme.com/book26-thumbs/page-106.jpg How do engineers test a bike helmet? Testers put a helmet on a head-shaped model that has sensors inside. They drop it onto a hard metal surface from a set height, so every helmet gets the same test. The sensors measure how much shock reaches the model’s head, and a helmet must stay below a safety limit to pass. Helmets must meet standards before they can be sold. Testers also check the straps. https://socialmedia.xdme.com/tony/videos-book26/page-106.mp4 https://www.youtube.com/embed/9fofwQAGsrE 104 2026-10-09T14:55:35+00:00 yes https://xdme.com/watch-book26-q107.html https://xdme.com/book26-thumbs/page-107.jpg How are toys tested to make sure they are safe? Toy testers check for small parts that could be a choking hazard for little children, sharp edges, loose eyes, and strong magnets. They drop, twist, and pull toys to see if pieces come off. Labs check paint and plastic for harmful chemicals. In Canada, toy rules are set by Health Canada. Age labels on boxes tell you who the toy is designed for. https://socialmedia.xdme.com/tony/videos-book26/page-107.mp4 https://www.youtube.com/embed/UF-_G5EpTBI 108 2026-10-09T14:55:36+00:00 yes https://xdme.com/watch-book26-q108.html https://xdme.com/book26-thumbs/page-108.jpg How do engineers test whether a building can survive shaking? In big labs, engineers build models of buildings and bridges and place them on a shake table, a platform that moves like an earthquake. Sensors record how the structure sways and where it is weak. Then they try new designs, like flexible joints or cross braces, and shake again. This helps buildings protect people in regions that have earthquakes. https://socialmedia.xdme.com/tony/videos-book26/page-108.mp4 https://www.youtube.com/embed/naWkMBXwlyI 110 2026-10-09T14:55:37+00:00 yes https://xdme.com/watch-book26-q109.html https://xdme.com/book26-thumbs/page-109.jpg How do machines test how long a product will last? A robot finger can press a phone button hundreds of thousands of times. Another machine opens and closes a laptop lid again and again. Makers do this to find out how long parts will last before they wear out. These tests are called durability or life tests. They are faster than waiting years, and show weak spots that need a better design. https://socialmedia.xdme.com/tony/videos-book26/page-109.mp4 https://www.youtube.com/embed/zykn6OHO73I 105 2026-10-09T15:02:08+00:00 yes https://xdme.com/watch-book26-q110.html https://xdme.com/book26-thumbs/page-110.jpg What do waterproof ratings like IP67 mean? IP stands for ingress protection. The first number tells how well a product keeps out dust, and the second tells how well it keeps out water. IP67, for example, means dust-tight and able to be under about one meter of water for 30 minutes. A higher number means better protection, but it does not mean a device is waterproof forever. https://socialmedia.xdme.com/tony/videos-book26/page-110.mp4 https://www.youtube.com/embed/X2cREmUoJzM 107 2026-10-09T15:02:09+00:00 yes https://xdme.com/watch-book26-q111.html https://xdme.com/book26-thumbs/page-111.jpg How do computers help inventors test ideas before building them? A computer simulation uses math rules for physics to show how a design might behave. It can show how air flows around a car, how a bridge bends, or how heat spreads in a gadget. Inventors can try hundreds of versions quickly and cheaply. But simulations are only as good as the rules behind them, so engineers still build and test real versions. https://socialmedia.xdme.com/tony/videos-book26/page-111.mp4 https://www.youtube.com/embed/8OPjaX6azus 108 2026-10-09T15:02:10+00:00 yes https://xdme.com/watch-book26-q112.html https://xdme.com/book26-thumbs/page-112.jpg Why do designers draw an invention on a computer first? Computer-aided design, or CAD, is software that lets designers draw shapes in three dimensions. They can rotate them, measure parts, and check whether pieces fit together. Changes are easy, and no material is wasted. The drawing can then be sent to machines that cut or print the parts. CAD is used for everything from toys to airplanes. https://socialmedia.xdme.com/tony/videos-book26/page-112.mp4 https://www.youtube.com/embed/3r_JwyyLTVs 108 2026-10-09T15:02:11+00:00 yes https://xdme.com/watch-book26-q113.html https://xdme.com/book26-thumbs/page-113.jpg Why do inventors ask other people to try their inventions? Inventors know their own creations too well. A friend might hold the product the wrong way, press the wrong button, or tell you it's too heavy. These clues show where a design is confusing. This is called user testing. Watching quietly, without helping, is often the best way to learn. Then the inventor fixes problems and tests again. https://socialmedia.xdme.com/tony/videos-book26/page-113.mp4 https://www.youtube.com/embed/GBd8FHYGKjY 107 2026-10-09T15:02:12+00:00 yes https://xdme.com/watch-book26-q114.html https://xdme.com/book26-thumbs/page-114.jpg Why do good instructions matter so much? A great invention is hard to use if directions are confusing. Clear instructions use simple words, numbered steps, and pictures. Designers test them by watching someone follow the steps for the first time. Where the person gets stuck, the instructions need work. Sometimes a product is designed so well that few instructions are needed at all. https://socialmedia.xdme.com/tony/videos-book26/page-114.mp4 https://www.youtube.com/embed/wIxNWO5GD0k 114 2026-10-09T15:02:12+00:00 yes https://xdme.com/watch-book26-q115.html https://xdme.com/book26-thumbs/page-115.jpg What do safety marks like CSA on a product mean? A mark such as CSA in Canada, or UL in the United States, shows that an independent lab tested a product against safety standards. It is common on electrical items such as chargers, lamps, and toasters. The lab checks that the item doesn't overheat or shock people during normal use. It does not mean a product is for play. Always follow the instructions. https://socialmedia.xdme.com/tony/videos-book26/page-115.mp4 https://www.youtube.com/embed/wd3JEselLkU 113 2026-10-09T15:02:13+00:00 yes https://xdme.com/watch-book26-q116.html https://xdme.com/book26-thumbs/page-116.jpg Why do companies sometimes recall products? A recall happens when a company or government learns a product may be unsafe after it has been sold. The maker asks people to stop using it and offers a repair, replacement, or refund. Recalls are common for toys with small parts or loose magnets, baby seats, bikes, and cars with faulty parts. In Canada, you can check for recalls on a government website. A recall is a way of fixing a mistake. https://socialmedia.xdme.com/tony/videos-book26/page-116.mp4 https://www.youtube.com/embed/orxC6K4rbVo 108 2026-10-09T15:02:14+00:00 yes https://xdme.com/watch-book26-q117.html https://xdme.com/book26-thumbs/page-117.jpg How did a peeler for sore hands lead to tools everyone likes to hold? In the late 1980s, an American businessman, Sam Farber, noticed that his wife Betsey, who had arthritis, had a hard time gripping a skinny metal vegetable peeler. He and a design team made kitchen tools with thick, soft, oval handles that are easy to hold. The tools helped people with sore hands, and they turned out to feel better to everyone. That is called universal design: making things easy for as many people as possible. https://socialmedia.xdme.com/tony/videos-book26/page-117.mp4 https://www.youtube.com/embed/N-LbURKOkic 114 2026-10-09T15:02:16+00:00 yes https://xdme.com/watch-book26-q118.html https://xdme.com/book26-thumbs/page-118.jpg Why do some inventors share their designs for free? Open-source means the plans for something are shared so anyone can use, copy, or improve them. Computer programs, small electronics boards, and some tools have been developed this way. Many people join in, find mistakes, and add new features. Sharing can make ideas spread faster than keeping them secret. Others choose to patent their inventions to earn money from them. https://socialmedia.xdme.com/tony/videos-book26/page-118.mp4 https://www.youtube.com/embed/FI5QwUnIxbM 111 2026-10-09T15:02:16+00:00 yes https://xdme.com/watch-book26-q119.html https://xdme.com/book26-thumbs/page-119.jpg What happens at a Maker Faire? A Maker Faire is a fair where makers show projects they've built, such as robots, art, electronics, costumes, and woodwork. Visitors can try activities, talk with the makers, and learn new skills. The first one was held in California in 2006. Now there are events around the world. Makers love to explain how they built their projects and inspire others to try. https://socialmedia.xdme.com/tony/videos-book26/page-119.mp4 https://www.youtube.com/embed/LToK84IljaE 111 2026-10-09T15:02:17+00:00 yes https://xdme.com/watch-book26-q120.html https://xdme.com/book26-thumbs/page-120.jpg How do inventors choose which materials to use? Inventors think about what the object must do. Does it need to be strong, light, bendy, waterproof, cheap, or safe to touch? Then they pick materials with those properties. A bike frame might be aluminum or carbon fiber, and a raincoat uses waterproof fabric. Inventors also think about how a material will be made, used, repaired, and recycled. https://socialmedia.xdme.com/tony/videos-book26/page-120.mp4 https://www.youtube.com/embed/-PokZExrAg4 108 2026-10-09T15:02:18+00:00 yes https://xdme.com/watch-book26-q121.html https://xdme.com/book26-thumbs/page-121.jpg How can inventions be designed so they are easy to repair or recycle? Some products are built with screws instead of glue, so parts can be replaced without throwing away the whole thing. Others use one kind of plastic so recycling is simpler. Designers also make spare parts available and provide guides. A product that lasts longer and can be fixed creates less trash. Thinking about the whole life of an invention is part of good design. https://socialmedia.xdme.com/tony/videos-book26/page-121.mp4 https://www.youtube.com/embed/uBHAKkjKDM0 107 2026-10-09T15:02:19+00:00 yes https://xdme.com/watch-book26-q122.html https://xdme.com/book26-thumbs/page-122.jpg Why do engineers sometimes test things until they break? Testing something to its breaking point shows how strong it truly is and where it fails first. For example, an airplane wing may be bent far beyond normal use in a lab. If it breaks only at a much higher force than ever happens in flight, engineers know there is a big safety margin. Learning how and where a design breaks helps make it safer. https://socialmedia.xdme.com/tony/videos-book26/page-122.mp4 https://www.youtube.com/embed/fQobfUZUkaA 105 2026-10-09T15:02:20+00:00 yes https://xdme.com/watch-book26-q123.html https://xdme.com/book26-thumbs/page-123.jpg Where can you see famous inventions in real life? Science museums and science centers keep real inventions and replicas, from early telephones to huge trains. In Canada, Ingenium in Ottawa runs museums of science and technology. Many cities have local history museums or heritage buildings. Seeing inventions up close helps you understand how they worked. Some museums even let you try hands-on exhibits. https://socialmedia.xdme.com/tony/videos-book26/page-123.mp4 https://www.youtube.com/embed/92ly6wrMa9M 112 2026-10-09T15:02:21+00:00 yes https://xdme.com/watch-book26-q124.html https://xdme.com/book26-thumbs/page-124.jpg Why do companies test a new idea in just one town first? Trying something new in a small place is called a pilot test. If it goes wrong, the problem is small and can be fixed. It also shows what real people think. A bus company might test a new route in one neighborhood, or a store might try a new product in a few shops. Then they change the idea and try again before going bigger. https://socialmedia.xdme.com/tony/videos-book26/page-124.mp4 https://www.youtube.com/embed/gRp14XLHkuE 101 2026-10-09T15:02:22+00:00 yes https://xdme.com/watch-book26-q125.html https://xdme.com/book26-thumbs/page-125.jpg How do you know an invention is ready to share with the world? A good checklist helps. Does it solve the problem it was meant for? Does it work every time you test it? Is it safe? Do clear instructions exist? Did others try it and give feedback? Have you written down how it was made? If you can answer yes, it may be ready. Even then, inventors keep improving and listening. https://socialmedia.xdme.com/tony/videos-book26/page-125.mp4 https://www.youtube.com/embed/hWb3NgiBS1E 104 2026-10-09T15:02:23+00:00 yes https://xdme.com/watch-book26-q126.html https://xdme.com/book26-thumbs/page-126.jpg How do you pick the best idea to build first? After a brainstorm, you will have many ideas, and you cannot build them all. Ask three questions of each one. Would it really fix the problem? Can I make a test version with things I have? Is it safe? Give each idea a score from 1 to 3 on each question and add them up. Build the idea with the top score. If it does not work, try the next one. https://socialmedia.xdme.com/tony/videos-book26/page-126.mp4 https://www.youtube.com/embed/RbuRyXS56AM 102 2026-10-09T15:02:24+00:00 yes https://xdme.com/watch-book26-q127.html https://xdme.com/book26-thumbs/page-127.jpg How do you brainstorm lots of ideas? Brainstorming means coming up with many ideas fast without judging them. Set a timer for five minutes and write or draw as many ways to solve your problem as you can. Silly ideas are welcome because they can spark good ones. Build on a friend's idea by saying "yes, and." Afterward, pick the best ideas and think about how to test them. https://socialmedia.xdme.com/tony/videos-book26/page-127.mp4 https://www.youtube.com/embed/U_MQ-2fjYLI 105 2026-10-09T15:02:25+00:00 yes https://xdme.com/watch-book26-q128.html https://xdme.com/book26-thumbs/page-128.jpg How can a sketch help you explain your idea? A sketch shows your idea without needing many words. Draw it from the front, side, and top. Add arrows to show motion, and labels to show parts. A sketch doesn't have to be pretty; it just has to be clear. Showing a drawing to others helps them give useful feedback and may reveal problems you hadn't noticed. https://socialmedia.xdme.com/tony/videos-book26/page-128.mp4 https://www.youtube.com/embed/RvG1a8Ge3NY 103 2026-10-09T15:02:26+00:00 yes https://xdme.com/watch-book26-q129.html https://xdme.com/book26-thumbs/page-129.jpg How can limits make you more creative? Limits, called constraints, are rules like size, cost, time, or the materials you may use. They can seem annoying but often force clever solutions. A challenge to build the tallest tower using only 20 index cards and no tape makes you think differently. Real inventors always face constraints, such as budget and safety. Working within limits is a key skill. https://socialmedia.xdme.com/tony/videos-book26/page-129.mp4 https://www.youtube.com/embed/N-ECHDZgNlU 112 2026-10-09T15:02:27+00:00 yes https://xdme.com/watch-book26-q130.html https://xdme.com/book26-thumbs/page-130.jpg How do cardboard mockups test whether a product fits a hand? A mockup is a quick model, made from cardboard, foam, or clay, in the same size as the real thing. Designers hold it, press pretend buttons, and see whether people can reach everything. Small and large hands try it, and the designers make changes. Fixing a cardboard model takes minutes. Fixing a finished product made with expensive tools can cost far more, so makers test cheap models first. https://socialmedia.xdme.com/tony/videos-book26/page-130.mp4 https://www.youtube.com/embed/eWVh8viO5V4 110 2026-10-09T15:02:28+00:00 yes https://xdme.com/watch-book26-q131.html https://xdme.com/book26-thumbs/page-131.jpg How can you invent with materials from the recycling bin? Boxes, cardboard tubes, bottle caps, jars, and egg cartons make great invention materials. Using them saves money and keeps stuff out of the trash. Look at each item and ask what it can do: a tube can roll things, a lid can spin, a box can hold. Always clean items and ask a grown-up to cut anything sharp or tough. https://socialmedia.xdme.com/tony/videos-book26/page-131.mp4 https://www.youtube.com/embed/tjc8zpvwnv8 107 2026-10-09T15:02:29+00:00 yes https://xdme.com/watch-book26-q132.html https://xdme.com/book26-thumbs/page-132.jpg How can you build a gadget using a lever or pulley? Levers and pulleys are simple machines that make work easier. A lever, like a ruler resting on a pencil, can lift a small weight by pushing down on the other end. A pulley changes the direction of a pull so you can lift by pulling down. You can build a mini crane that lifts a small bucket using a spool, string, and a stick. https://socialmedia.xdme.com/tony/videos-book26/page-132.mp4 https://www.youtube.com/embed/mejp1Ewua1w 102 2026-10-09T15:05:31+00:00 yes https://xdme.com/watch-book26-q133.html https://xdme.com/book26-thumbs/page-133.jpg Can you build a car pushed by a paper sail? Yes! Sailboats on water use wind, and so can a little car on land. Build a small car with bottle-cap wheels on straw axles, and tape on a paper sail held by a straw mast. Blow gently from behind or use a hand fan. A bigger sail catches more wind, but it also adds weight. Try different sail sizes and shapes. Which version goes the farthest? That is how inventors improve ideas. https://socialmedia.xdme.com/tony/videos-book26/page-133.mp4 https://www.youtube.com/embed/U8i3ySXKaVg 108 2026-10-09T15:05:32+00:00 yes https://xdme.com/watch-book26-q134.html https://xdme.com/book26-thumbs/page-134.jpg How do you invent a new game? Start by choosing a goal, such as getting a ball in a bucket or collecting the most cards. Then decide the rules: how many players, how turns work, how to win, and what to do when someone breaks a rule. Test it with friends and watch for what's confusing or unfair. Change the rules and try again. Great games are fun and fair. https://socialmedia.xdme.com/tony/videos-book26/page-134.mp4 https://www.youtube.com/embed/YeUJzT-4PLc 103 2026-10-09T15:05:32+00:00 yes https://xdme.com/watch-book26-q135.html https://xdme.com/book26-thumbs/page-135.jpg Can you invent a helper for an everyday chore? Many chores have room for improvement. You could design a scoop for kitty food, a clip to hold a cleaning bag open, or a holder for books on a bed. First, watch how the chore is done and where it is hard. Then sketch ideas, build a rough model, and test with real use. Always check that your invention is safe and doesn't need heat or sharp tools. https://socialmedia.xdme.com/tony/videos-book26/page-135.mp4 https://www.youtube.com/embed/ajn72vg_6IM 103 2026-10-09T15:05:33+00:00 yes https://xdme.com/watch-book26-q136.html https://xdme.com/book26-thumbs/page-136.jpg How would you design a better backpack? Think about the problems: heavy straps, items sinking to the bottom, or zippers that get stuck. Design questions include where to put pockets, how to spread weight over both shoulders, and what materials are lightweight but strong. Interview friends about what they carry. Then sketch and make a model with cloth or paper. Good design starts with how real people use things. https://socialmedia.xdme.com/tony/videos-book26/page-136.mp4 https://www.youtube.com/embed/HE89IqulzQg 105 2026-10-09T15:05:34+00:00 yes https://xdme.com/watch-book26-q137.html https://xdme.com/book26-thumbs/page-137.jpg How can you design a lunch box that keeps food safe for a few hours? Germs grow quickly when food sits between about 40 and 140 degrees Fahrenheit for more than two hours. Cold foods need to stay cold. An insulated lunch bag slows the heat coming in. Pack a frozen gel pack or a frozen juice box next to the food, and keep the bag out of the sun. Warm foods can go in a thermos that has been warmed with hot water first. https://socialmedia.xdme.com/tony/videos-book26/page-137.mp4 https://www.youtube.com/embed/atzKU3mSjiA 111 2026-10-09T15:05:35+00:00 yes https://xdme.com/watch-book26-q138.html https://xdme.com/book26-thumbs/page-138.jpg How can you invent a musical instrument from household things? Sound comes from vibrations. You can make a rubber-band guitar by stretching bands across a box, a kazoo with a comb and wax paper, or a shaker with beans in a container. Changing the length, thickness, or tightness changes the pitch. Try different materials to hear what sounds best. Always use safe materials and ask a grown-up for help. https://socialmedia.xdme.com/tony/videos-book26/page-138.mp4 https://www.youtube.com/embed/EDZC9acCKzk 111 2026-10-09T15:05:36+00:00 yes https://xdme.com/watch-book26-q139.html https://xdme.com/book26-thumbs/page-139.jpg How do you design a toy for a younger sibling? Toys for little kids must be safe. Avoid small parts that can be swallowed, sharp edges, and anything that can pinch. Use soft or smooth materials, bright colors, and sizes bigger than a fist. Try it with the younger child while a grown-up watches. Notice what they do with it, since little kids often use toys in surprising ways. That is the best user test. https://socialmedia.xdme.com/tony/videos-book26/page-139.mp4 https://www.youtube.com/embed/9JTVNzBVccE 105 2026-10-09T15:05:37+00:00 yes https://xdme.com/watch-book26-q140.html https://xdme.com/book26-thumbs/page-140.jpg How do you improve an invention again and again? Making something better in steps is called iteration. Build a version, test it, find what's wrong, and fix it. Then build version two and test again. Each round teaches something. Write down changes so you can see what helped. Some inventions go through hundreds of versions, but even three rounds can make your project much better. https://socialmedia.xdme.com/tony/videos-book26/page-140.mp4 https://www.youtube.com/embed/jmrRGgL3Xf0 108 2026-10-09T15:05:38+00:00 yes https://xdme.com/watch-book26-q141.html https://xdme.com/book26-thumbs/page-141.jpg How do you give your invention a good name and a short pitch? A name should be easy to say and give a hint about what your invention does. A pitch is a short talk, about 30 seconds, explaining the problem, your solution, and why it helps. Practice in front of a mirror or family. Use clear words and show it if you can. A good pitch makes people want to learn more about your invention. https://socialmedia.xdme.com/tony/videos-book26/page-141.mp4 https://www.youtube.com/embed/s_8SbHV3g-I 104 2026-10-09T15:05:40+00:00 yes https://xdme.com/watch-book26-q142.html https://xdme.com/book26-thumbs/page-142.jpg How can a comic explain how your invention works? A comic strip shows a story in steps. In panel one, show the problem. In panel two, show your invention. In panel three, show it working. Add speech bubbles and labels. Comics are good for explaining ideas to people of many ages. Patent drawings and instruction sheets also use pictures to show steps clearly. https://socialmedia.xdme.com/tony/videos-book26/page-142.mp4 https://www.youtube.com/embed/5Vf8o3c9yLo 109 2026-10-09T15:05:40+00:00 yes https://xdme.com/watch-book26-q143.html https://xdme.com/book26-thumbs/page-143.jpg How do you make a good poster for a science or invention fair? A good poster has a clear title, a short explanation, a drawing or photo, and your results. Use large letters and bright, simple colors. Divide it into sections: Problem, Idea, How I Tested, What I Learned. Don't pack in too many words. Practice explaining it aloud, because people will ask questions. Be proud of your work and be ready to admit what you still don't know. https://socialmedia.xdme.com/tony/videos-book26/page-143.mp4 https://www.youtube.com/embed/6wSMr_gTUNM 109 2026-10-09T15:05:41+00:00 yes https://xdme.com/watch-book26-q144.html https://xdme.com/book26-thumbs/page-144.jpg How can a team work well on an invention? Teams share many ideas and skills. Give everyone a role, such as builder, tester, drawer, and recorder, and switch roles sometimes. Listen to each person, and agree on a plan before you start. If you disagree, test both ideas. Respect and kindness matter just as much as clever thinking. Many famous inventions were made by teams working together over years. https://socialmedia.xdme.com/tony/videos-book26/page-144.mp4 https://www.youtube.com/embed/R_Aogjs_uBU 108 2026-10-09T15:05:42+00:00 yes https://xdme.com/watch-book26-q145.html https://xdme.com/book26-thumbs/page-145.jpg What are good rules for a safe inventor's workspace? Pick a clear table, cover it if needed, and keep a clean floor. Wear safety goggles when cutting or hammering, and let grown-ups handle knives, hot tools, power tools, and anything electrical from the wall. Keep batteries and magnets away from small children and pets. Wash your hands after working, and tidy up when you finish. https://socialmedia.xdme.com/tony/videos-book26/page-145.mp4 https://www.youtube.com/embed/tt8la9SK8wA 108 2026-10-09T15:05:43+00:00 yes https://xdme.com/watch-book26-q146.html https://xdme.com/book26-thumbs/page-146.jpg What can you do when your invention gets stuck? Everyone gets stuck sometimes. Take a break, then look at the problem again. Ask a friend to try it and tell you what they see. Break the big problem into smaller parts and fix one at a time. Try a completely different approach. Check your notes to see what you've already tried. Often a new idea comes when you step away and then return. https://socialmedia.xdme.com/tony/videos-book26/page-146.mp4 https://www.youtube.com/embed/jDfjGZX3beE 98 2026-10-09T15:05:44+00:00 yes https://xdme.com/watch-book26-q147.html https://xdme.com/book26-thumbs/page-147.jpg How can you invent something that helps your community? Look around your neighborhood for needs. Perhaps a bus stop needs shade, a park needs better trash bins for recycling, or neighbors could use a way to share tools. Talk to the people involved to understand the problem. Then design a simple solution and share it with leaders or neighbors. Even small ideas can make life better for many people. https://socialmedia.xdme.com/tony/videos-book26/page-147.mp4 https://www.youtube.com/embed/eb7ZI21Y-pg 107 2026-10-09T15:05:45+00:00 yes https://xdme.com/watch-book26-q148.html https://xdme.com/book26-thumbs/page-148.jpg How can inventors make things that are kind to the planet? Eco-design means thinking about the whole life of a product: where the materials come from, how much energy it uses, how long it lasts, and what happens when it is thrown away. Inventors can use recycled or plant-based materials, make things easy to repair, and design products that use less power. Small choices in design can add up to a big difference. https://socialmedia.xdme.com/tony/videos-book26/page-148.mp4 https://www.youtube.com/embed/UIAbyJAGADs 110 2026-10-09T15:05:46+00:00 yes https://xdme.com/watch-book26-q149.html https://xdme.com/book26-thumbs/page-149.jpg Who can help you with your invention? Inventors rarely work alone. Parents and teachers can help find materials and keep you safe. Librarians can help you research. Makers and engineers in your community might share advice, and many museums and clubs run workshops for kids. Online, always ask a grown-up before sharing anything. Asking for help is a sign of a good inventor. https://socialmedia.xdme.com/tony/videos-book26/page-149.mp4 https://www.youtube.com/embed/WDHpdyGikjQ 110 2026-10-09T15:05:48+00:00 yes https://xdme.com/watch-book26-q150.html https://xdme.com/book26-thumbs/page-150.jpg What will you invent first? The world needs new ideas, and yours matter. Choose a small problem, brainstorm, sketch, build a simple model, test it fairly, and improve it. Be patient and curious, and learn from mistakes just as many inventors did. You can start today with paper, tape, and imagination. Whatever you make, keep asking questions and keep making. Who knows what you will create? https://socialmedia.xdme.com/tony/videos-book26/page-150.mp4 https://www.youtube.com/embed/vvqckDn48uM 108 2026-10-09T15:05:50+00:00 yes https://xdme.com/watch-book27-q001.html https://xdme.com/book27-thumbs/page-001.jpg What is a crystal? A crystal is a solid whose tiny building blocks, called atoms or molecules, are lined up in a neat, repeating pattern that goes in every direction. Salt, sugar, ice, quartz, and even the metal in a spoon are made of crystals. Some crystals are big and shiny, but most are too small to see without a magnifier, so crystals are hiding all around you. https://socialmedia.xdme.com/tony/videos-book27/page-001.mp4 https://www.youtube.com/embed/Cdn3SqyqEOo 110 2026-10-09T14:43:31+00:00 yes https://xdme.com/watch-book27-q002.html https://xdme.com/book27-thumbs/page-002.jpg Why do the atoms in a crystal line up in a pattern? Atoms and molecules attract each other, and they settle into the arrangement that uses the least energy, which is usually a tidy repeating pattern. Imagine stacking boxes in a warehouse: neat rows fit better than a jumble. This repeating three-dimensional grid is called a lattice. Because the pattern repeats, a tiny piece of a crystal has the same arrangement as a huge one. https://socialmedia.xdme.com/tony/videos-book27/page-002.mp4 https://www.youtube.com/embed/u2bkNzaf8LA 108 2026-10-09T14:43:32+00:00 yes https://xdme.com/watch-book27-q003.html https://xdme.com/book27-thumbs/page-003.jpg Why do crystals have flat sides and sharp corners? Crystals grow outward by adding one layer of atoms at a time, and every layer follows the same pattern as the one under it. The flat faces you see are the outer edges of those neat layers. The corners are where flat faces meet. When a crystal has room to grow without bumping into anything, those smooth faces and sharp points can look like they were cut by a jeweler. https://socialmedia.xdme.com/tony/videos-book27/page-003.mp4 https://www.youtube.com/embed/NQoIglvIuXU 106 2026-10-09T14:43:32+00:00 yes https://xdme.com/watch-book27-q004.html https://xdme.com/book27-thumbs/page-004.jpg Why does the same crystal always have the same angles? In 1669, a Danish scientist named Nicolas Steno measured quartz crystals from many places and noticed that the angle between two matching faces was always the same, no matter how big or small the crystal. That happens because the faces follow the lattice inside, and the lattice never changes. Mineral experts still use these angles as clues to identify crystals. https://socialmedia.xdme.com/tony/videos-book27/page-004.mp4 https://www.youtube.com/embed/7f4hJYWVpwE 113 2026-10-09T14:43:34+00:00 yes https://xdme.com/watch-book27-q005.html https://xdme.com/book27-thumbs/page-005.jpg How many different crystal shapes are there? Scientists sort crystals into seven main groups, called crystal systems, based on the shape of their repeating box. These are cubic, tetragonal, orthorhombic, hexagonal, trigonal, monoclinic, and triclinic. Table salt is cubic. Quartz crystals look six-sided, but they belong to the trigonal group, while beryl is hexagonal. There are thousands of kinds of minerals, but they all fit into these seven families. https://socialmedia.xdme.com/tony/videos-book27/page-005.mp4 https://www.youtube.com/embed/400xLnymKxg 115 2026-10-09T14:43:36+00:00 yes https://xdme.com/watch-book27-q006.html https://xdme.com/book27-thumbs/page-006.jpg What is symmetry in a crystal? Symmetry means that a shape looks the same after you flip, turn, or mirror it. A snowflake-like hexagon can be turned a sixth of a turn and look unchanged. A cube has many mirror planes. Crystals have symmetry because their lattice repeats in an orderly way. Scientists use symmetry to organize crystals into groups and to predict how they will break, bend, or shine. https://socialmedia.xdme.com/tony/videos-book27/page-006.mp4 https://www.youtube.com/embed/AL4Zeub1LJk 111 2026-10-09T14:43:38+00:00 yes https://xdme.com/watch-book27-q007.html https://xdme.com/book27-thumbs/page-007.jpg Is glass a crystal? No. Ordinary glass is made by melting sand with a few other ingredients and then cooling it so fast that the atoms freeze in place before they can line up. The atoms are jumbled like a crowd instead of lined up like a marching band. That kind of solid is called amorphous. Glass breaks into curved, shell-like pieces, while real crystals tend to break along flat lines. Because glass has no crystal faces, it can be shaped into windows and lenses. https://socialmedia.xdme.com/tony/videos-book27/page-007.mp4 https://www.youtube.com/embed/kcepXQaYKiE 114 2026-10-09T14:43:39+00:00 yes https://xdme.com/watch-book27-q008.html https://xdme.com/book27-thumbs/page-008.jpg Why do some crystals split along flat lines? Inside a crystal, atoms are held together more weakly in some directions than in others. When the crystal is tapped or hit, it can split along those weak flat planes. This is called cleavage. Mica splits into thin, bendy sheets, and calcite breaks into slanted blocks. Gem cutters study cleavage so they can split big stones the safe, smart way. https://socialmedia.xdme.com/tony/videos-book27/page-008.mp4 https://www.youtube.com/embed/0BfVQE4GA8Q 110 2026-10-09T14:43:40+00:00 yes https://xdme.com/watch-book27-q009.html https://xdme.com/book27-thumbs/page-009.jpg What is the difference between a crystal, a mineral, and a rock? A mineral is a natural solid with a particular chemical makeup and a crystal structure, like quartz or salt. A crystal describes the neat shape and pattern a mineral can have. A rock is usually a mix of one or more minerals packed together, such as granite, which holds quartz and other crystals. So rocks are made of mineral grains, and those grains are often tiny crystals. https://socialmedia.xdme.com/tony/videos-book27/page-009.mp4 https://www.youtube.com/embed/I4oQVQDxS4M 110 2026-10-09T14:43:42+00:00 yes https://xdme.com/watch-book27-q010.html https://xdme.com/book27-thumbs/page-010.jpg How can diamond and pencil graphite both be made of carbon? Diamond and graphite are made of the same atoms, carbon, but arranged differently. In diamond, each carbon atom is locked to four neighbors in a strong 3D lattice, making it the hardest natural material. In graphite, carbon atoms form flat sheets that slide over each other, so it is soft and slippery. The same atoms can act very differently when their pattern changes. https://socialmedia.xdme.com/tony/videos-book27/page-010.mp4 https://www.youtube.com/embed/Pcm51N7nDs0 106 2026-10-09T14:43:42+00:00 yes https://xdme.com/watch-book27-q011.html https://xdme.com/book27-thumbs/page-011.jpg Why do atoms stack like oranges in a crystal? When you stack oranges at a store, the pile is steadiest and holds the most when each layer sits in the dips of the layer below. Many crystals pack atoms the same way, because that arrangement wastes the least space. Scientists call this close packing. Metals like copper and aluminum often follow this pattern, which helps explain why they are dense and strong. https://socialmedia.xdme.com/tony/videos-book27/page-011.mp4 https://www.youtube.com/embed/YOsUhQPiW8w 106 2026-10-09T14:43:44+00:00 yes https://xdme.com/watch-book27-q012.html https://xdme.com/book27-thumbs/page-012.jpg Are metals made of crystals? Yes. A piece of metal is made of countless tiny crystals called grains, each one a block of lined-up atoms, all packed together. Bending a metal paper clip makes layers of atoms slide, which is why metals can bend instead of snapping. Blacksmiths, steelmakers, and engineers shape and heat metals to change their grains and make the metal tougher. https://socialmedia.xdme.com/tony/videos-book27/page-012.mp4 https://www.youtube.com/embed/QHiAFcKi_xY 108 2026-10-09T14:43:45+00:00 yes https://xdme.com/watch-book27-q013.html https://xdme.com/book27-thumbs/page-013.jpg Is ice a crystal? Yes. When water freezes, its molecules lock into a six-sided pattern with open spaces between them. That pattern is a crystal lattice, and it is why ice crystals often have six sides. The open spaces also make ice less dense than liquid water, so it floats. Frost on a window, ice cubes, and glaciers are all made of ice crystals. https://socialmedia.xdme.com/tony/videos-book27/page-013.mp4 https://www.youtube.com/embed/W2ftF-v12Zc 107 2026-10-09T14:43:47+00:00 yes https://xdme.com/watch-book27-q014.html https://xdme.com/book27-thumbs/page-014.jpg Why do some crystals grow as needles and others as cubes? The shape of a crystal depends on its internal lattice and on where it grows. Some faces grow faster than others, which stretches the crystal into needles, plates, or blocks. Temperature, space, and the other chemicals around the crystal all matter. That is why the same mineral can look different in different places, and why experts also test hardness and color before naming it. https://socialmedia.xdme.com/tony/videos-book27/page-014.mp4 https://www.youtube.com/embed/2jEQIhexm18 111 2026-10-09T14:43:48+00:00 yes https://xdme.com/watch-book27-q015.html https://xdme.com/book27-thumbs/page-015.jpg How do scientists look inside a crystal? Scientists use X-rays. When a beam of X-rays passes through a crystal, the repeating layers of atoms bend the rays, creating a pattern of spots on a detector. Experts work backward from the pattern to figure out where each atom sits. This method is called X-ray crystallography. It has revealed the structures of metals, medicines, and even the molecules in living things. https://socialmedia.xdme.com/tony/videos-book27/page-015.mp4 https://www.youtube.com/embed/ZU3trQG_LEk 112 2026-10-09T14:43:49+00:00 yes https://xdme.com/watch-book27-q016.html https://xdme.com/book27-thumbs/page-016.jpg How did a father and son discover how crystals are built? In 1912 and 1913, the British physicists William Henry Bragg and his son William Lawrence Bragg showed that X-rays bouncing off the layers of atoms in a crystal make a pattern that reveals the atoms' positions. They first solved the structure of table salt. The two shared the 1915 Nobel Prize in Physics, and the son, at age 25, is still the youngest person to win it. https://socialmedia.xdme.com/tony/videos-book27/page-016.mp4 https://www.youtube.com/embed/YvtCKY2WXy0 113 2026-10-09T14:43:50+00:00 yes https://xdme.com/watch-book27-q017.html https://xdme.com/book27-thumbs/page-017.jpg How small can a crystal be? Crystals can be tiny, down to just a few nanometers wide. A nanometer is a billionth of a meter, tens of thousands of times thinner than a human hair. These nanocrystals can act differently from large ones, glowing different colors depending on their size. Some TV screens use tiny crystals called quantum dots to make bright colors. https://socialmedia.xdme.com/tony/videos-book27/page-017.mp4 https://www.youtube.com/embed/A4-PsPR4p2c 107 2026-10-09T14:43:51+00:00 yes https://xdme.com/watch-book27-q018.html https://xdme.com/book27-thumbs/page-018.jpg What is the biggest crystal ever found? In a mine in Naica, Mexico, workers found a cave filled with giant beams of gypsum, a soft white mineral. Some are about 36 feet long and weigh dozens of tons. They grew slowly for hundreds of thousands of years in warm, mineral-rich water. The cave was so hot and humid that scientists wore cooling suits and could stay only a short time. https://socialmedia.xdme.com/tony/videos-book27/page-018.mp4 https://www.youtube.com/embed/pLIH0qgSSsY 108 2026-10-09T14:43:52+00:00 yes https://xdme.com/watch-book27-q019.html https://xdme.com/book27-thumbs/page-019.jpg Are crystals alive? No. Crystals don't eat, breathe, or have cells. They grow because new atoms or molecules attach to the outside in the same pattern, which is a physical process, not a living one. A crystal can stop growing if the liquid runs out. It doesn't reproduce or respond like a living thing. But watching crystals grow can look almost like watching a plant. https://socialmedia.xdme.com/tony/videos-book27/page-019.mp4 https://www.youtube.com/embed/k0TFGPN1ukI 105 2026-10-09T14:43:53+00:00 yes https://xdme.com/watch-book27-q020.html https://xdme.com/book27-thumbs/page-020.jpg Is "crystal" glassware real crystal? Not in the science sense. Fancy glassware is usually called crystal because it is clearer and sparkles more than ordinary glass. But it is still glass, with atoms in a jumbled pattern. Traditional lead crystal had lead added, which makes glass heavier and more brilliant. Many people today use lead-free versions. Real crystals like quartz have an orderly lattice. https://socialmedia.xdme.com/tony/videos-book27/page-020.mp4 https://www.youtube.com/embed/YeYn3LLMGP8 110 2026-10-09T14:43:54+00:00 yes https://xdme.com/watch-book27-q021.html https://xdme.com/book27-thumbs/page-021.jpg Do crystals have special powers? People love crystals for their beauty and have long made up stories about them. But careful tests have not found that crystals can heal people or bring luck. What science can say is that crystals really are amazing: they keep time in watches, carry phone signals, and power computers. Enjoy a crystal for its beauty and its real science. https://socialmedia.xdme.com/tony/videos-book27/page-021.mp4 https://www.youtube.com/embed/mRFQAQWFpaY 111 2026-10-09T14:43:56+00:00 yes https://xdme.com/watch-book27-q022.html https://xdme.com/book27-thumbs/page-022.jpg What makes some crystals see-through and others milky? A perfectly clear crystal lets light pass straight through. Cloudy crystals often have tiny cracks, bubbles, or other minerals trapped inside that scatter the light. Quartz can be clear, like glass, or milky white if full of tiny bubbles. Slow, calm growth tends to make clearer crystals because there is time for atoms to settle neatly. Rock crystal is the name for very clear quartz. https://socialmedia.xdme.com/tony/videos-book27/page-022.mp4 https://www.youtube.com/embed/KyK45CZWjfw 108 2026-10-09T14:43:57+00:00 yes https://xdme.com/watch-book27-q023.html https://xdme.com/book27-thumbs/page-023.jpg What is the smallest repeating piece of a crystal? The smallest repeating block is called a unit cell. Imagine a LEGO brick that can be stacked up, down, and sideways to build the whole crystal. Every unit cell has the same atoms in the same places. Different minerals have different unit cells. Scientists use the shape and size of the unit cell to describe a crystal's structure and compare it with others. https://socialmedia.xdme.com/tony/videos-book27/page-023.mp4 https://www.youtube.com/embed/p0CKEAPp3YQ 107 2026-10-09T14:43:58+00:00 yes https://xdme.com/watch-book27-q024.html https://xdme.com/book27-thumbs/page-024.jpg Why does a salt crystal shatter, but a metal paper clip bends? In salt, charged particles alternate in a pattern, with plus next to minus. If a layer slides over by one step, plus faces plus and the particles push apart, so the crystal splits. In a metal, atoms are surrounded by a flowing sea of electrons that holds them together, so layers can slide without breaking. That is why metals bend and many crystals are brittle. https://socialmedia.xdme.com/tony/videos-book27/page-024.mp4 https://www.youtube.com/embed/j3zWB1Z7LXc 107 2026-10-09T14:44:00+00:00 yes https://xdme.com/watch-book27-q025.html https://xdme.com/book27-thumbs/page-025.jpg How can you spot crystals at home? Look for flat shiny faces, straight edges, and sparkle that flashes when you move. Salt and sugar are crystals. Ice is a crystal. Many sand grains are tiny quartz crystals. The granite on a counter is full of crystals too. A magnifier or a microscope will show more details, and shining a flashlight from different angles helps you see their flat faces. https://socialmedia.xdme.com/tony/videos-book27/page-025.mp4 https://www.youtube.com/embed/Qa9DxIlOd6g 109 2026-10-09T14:44:01+00:00 yes https://xdme.com/watch-book27-q026.html https://xdme.com/book27-thumbs/page-026.jpg How does a crystal begin to grow? A crystal begins when a few atoms or molecules in a liquid or gas happen to bump together in the right pattern and stick. This tiny starter group is called a nucleus. Once it forms, more particles attach to it layer by layer, and it grows. Dust specks, scratches, or rough surfaces can give particles a place to start, which is why crystals often begin on edges and corners. https://socialmedia.xdme.com/tony/videos-book27/page-026.mp4 https://www.youtube.com/embed/mo4Mwz_fH_g 112 2026-10-09T14:44:02+00:00 yes https://xdme.com/watch-book27-q027.html https://xdme.com/book27-thumbs/page-027.jpg Why does a tiny seed crystal help a big one grow? A seed crystal is a small, ready-made crystal that gives atoms a perfect place to attach. Instead of making lots of new tiny crystals everywhere, the dissolved material adds to the seed, making one big crystal. That is why rock candy makers use a string coated with sugar crystals, and why labs use seeds when they want large, clear crystals for technology. https://socialmedia.xdme.com/tony/videos-book27/page-027.mp4 https://www.youtube.com/embed/RKqWmtBmMB4 109 2026-10-09T14:44:04+00:00 yes https://xdme.com/watch-book27-q028.html https://xdme.com/book27-thumbs/page-028.jpg Why do slow-growing crystals get bigger than fast-growing ones? When a crystal grows slowly, atoms have time to find the perfect spot, so the crystal can get big and clear. When a solution cools or dries quickly, thousands of tiny crystals start at once, and they run out of material before any gets large. This is why cooling speed makes a huge difference in the size of crystals in science, cooking, and nature. https://socialmedia.xdme.com/tony/videos-book27/page-028.mp4 https://www.youtube.com/embed/SRSjEyx83XA 109 2026-10-09T14:44:05+00:00 yes https://xdme.com/watch-book27-q029.html https://xdme.com/book27-thumbs/page-029.jpg What does supersaturated mean? Warm water can dissolve more of some substances than cold water. If you make a hot, nearly full solution and let it cool gently, the water may hold more dissolved stuff than it normally could at that cooler temperature. We call that supersaturated. It is unstable, like a ball balanced on a hill, so crystals start growing and use up the extra. https://socialmedia.xdme.com/tony/videos-book27/page-029.mp4 https://www.youtube.com/embed/HA7rmtpDHvA 111 2026-10-09T14:44:06+00:00 yes https://xdme.com/watch-book27-q030.html https://xdme.com/book27-thumbs/page-030.jpg How do crystals appear when salty water dries up? When water evaporates, it leaves behind whatever was dissolved in it. As the water level shrinks, the salts become more crowded until they cannot stay dissolved, and crystals start to form, often along the edges where evaporation is fastest. This is how sea salt is collected in shallow pools, and how white rings appear on a boot after it dries. https://socialmedia.xdme.com/tony/videos-book27/page-030.mp4 https://www.youtube.com/embed/Fpbbtl2Uv4w 110 2026-10-09T14:44:07+00:00 yes https://xdme.com/watch-book27-q031.html https://xdme.com/book27-thumbs/page-031.jpg Why do some rocks have a few big crystals sitting in tiny ones? Some rocks, called porphyry, look like a speckled cookie. Big crystals sit in a background of tiny ones. This happens when melted rock starts to cool slowly deep underground, which lets a few crystals grow big. Then the rest of the melt rises or erupts and cools quickly, so the leftover liquid makes tiny crystals around the big ones. The rock keeps a record of two cooling speeds. https://socialmedia.xdme.com/tony/videos-book27/page-031.mp4 https://www.youtube.com/embed/n38E9-2VSVE 111 2026-10-09T14:44:09+00:00 yes https://xdme.com/watch-book27-q032.html https://xdme.com/book27-thumbs/page-032.jpg How does a hollow rock fill up with crystals? A geode starts as a hollow space inside rock, like a gas bubble in old lava or a gap in limestone. Over thousands to millions of years, water seeps in carrying dissolved minerals such as silica. The minerals line the walls, first with a thin layer and then with crystals that grow slowly into the empty space. If the cavity fills completely, it becomes a solid nodule. https://socialmedia.xdme.com/tony/videos-book27/page-032.mp4 https://www.youtube.com/embed/ia8SNtXtLTM 108 2026-10-09T14:44:10+00:00 yes https://xdme.com/watch-book27-q033.html https://xdme.com/book27-thumbs/page-033.jpg Why do the crystals in a geode point toward the middle? Crystals grow from wall surfaces outward into any open space. In a geode, the wall is the starting place, so each crystal sprouts from the wall and points into the empty middle, where it has the most room. Crystals growing next to each other squeeze and compete, which is why some are thin at the base and wider at the tip. It looks like a tiny crystal cave. https://socialmedia.xdme.com/tony/videos-book27/page-033.mp4 https://www.youtube.com/embed/qqcztgcyJc4 104 2026-10-09T14:44:11+00:00 yes https://xdme.com/watch-book27-q034.html https://xdme.com/book27-thumbs/page-034.jpg How can a paper-thin slice of rock show its crystals? Geologists cut a very thin slice of rock, only about as thick as a hair, and glue it to a piece of glass. At that thickness, light can pass through the crystals. Under a special microscope with polarized light, each mineral shows its own colors and patterns. By looking at the size, shape, and colors of the crystals, geologists can name the minerals and learn how the rock formed. https://socialmedia.xdme.com/tony/videos-book27/page-034.mp4 https://www.youtube.com/embed/MefGRFvflPM 109 2026-10-09T14:44:12+00:00 yes https://xdme.com/watch-book27-q035.html https://xdme.com/book27-thumbs/page-035.jpg How does temperature change which crystals form? When melted rock cools, different minerals become solid at different temperatures. Some crystals form first at high temperatures, while others wait until it is cooler. So the first crystals can float or sink before the rest freeze around them. Scientists read the mix of crystals in a rock to learn how hot it was and how it cooled, like reading a recipe. https://socialmedia.xdme.com/tony/videos-book27/page-035.mp4 https://www.youtube.com/embed/5BNCV2yC7TI 108 2026-10-09T14:44:13+00:00 yes https://xdme.com/watch-book27-q036.html https://xdme.com/book27-thumbs/page-036.jpg Can crystals grow better in space? On Earth, gravity makes liquids move in little currents, which can disturb a growing crystal. On the International Space Station, astronauts grow crystals of proteins and other substances in microgravity, where the liquid is calmer. Sometimes the crystals come out larger or more perfect. Scientists study them on Earth with X-rays to help design new medicines and materials. https://socialmedia.xdme.com/tony/videos-book27/page-036.mp4 https://www.youtube.com/embed/eSI0VLLX-nE 90 2026-10-09T14:44:14+00:00 yes https://xdme.com/watch-book27-q037.html https://xdme.com/book27-thumbs/page-037.jpg Do living things make crystals? Yes! Your bones and teeth contain tiny crystals of a calcium mineral that make them hard. Seashells are crystals of calcium carbonate. Inside your inner ear are tiny calcium carbonate crystals that help your balance, like little weights that shift when you tilt your head. Some bacteria even make tiny magnetic crystals to sense Earth's magnetic field. https://socialmedia.xdme.com/tony/videos-book27/page-037.mp4 https://www.youtube.com/embed/XdoTJ4ZLMSc 110 2026-10-09T14:44:15+00:00 yes https://xdme.com/watch-book27-q038.html https://xdme.com/book27-thumbs/page-038.jpg What is hoarfrost, and why does it make trees look furry white? Hoarfrost forms on clear, cold, still nights. Water vapor in the air turns straight into ice crystals on cold surfaces such as twigs, grass, wires, and fence posts. The crystals grow into spiky feathers and needles, which can make a whole tree look furry and white. It is different from frost on a window, because it grows outside on thin things that cool off fast. When the Sun rises, it melts away. https://socialmedia.xdme.com/tony/videos-book27/page-038.mp4 https://www.youtube.com/embed/l5qF0mFc2-4 113 2026-10-09T14:44:17+00:00 yes https://xdme.com/watch-book27-q039.html https://xdme.com/book27-thumbs/page-039.jpg Why do bismuth crystals look like staircases? Bismuth is a metal that grows into square spiral shapes called hopper crystals. The edges grow faster than the middles, which leaves stepped hollows like a staircase. A thin layer of oxide forms on the surface, and light reflecting from it makes rainbow colors. Scientists grow bismuth crystals in labs by carefully melting and cooling it. Don't try melting metal at home. https://socialmedia.xdme.com/tony/videos-book27/page-039.mp4 https://www.youtube.com/embed/A-d0O5UT1wA 110 2026-10-09T14:44:18+00:00 yes https://xdme.com/watch-book27-q040.html https://xdme.com/book27-thumbs/page-040.jpg How long do crystals take to grow in nature? It depends. Frost crystals can grow in minutes, and salt crystals can grow in hours or days. Some mineral crystals in caves and rocks take thousands or even millions of years to reach the size we see. The giant gypsum crystals in the Mexican cave may have grown for about half a million years. Diamonds, formed deep in the Earth, took far longer still. https://socialmedia.xdme.com/tony/videos-book27/page-040.mp4 https://www.youtube.com/embed/GH-Dyg3EZ9A 108 2026-10-09T14:44:19+00:00 yes https://xdme.com/watch-book27-q041.html https://xdme.com/book27-thumbs/page-041.jpg What makes a growing crystal stop? A crystal stops growing when there is nothing left to add. The liquid may run out of dissolved material, the temperature may change, or the crystal may bump into the wall or another crystal. Sometimes changing conditions even dissolve part of the crystal. When the crystal is finished, it holds a record of the conditions in which it grew. https://socialmedia.xdme.com/tony/videos-book27/page-041.mp4 https://www.youtube.com/embed/2JsxPZ24a8o 107 2026-10-09T14:44:21+00:00 yes https://xdme.com/watch-book27-q042.html https://xdme.com/book27-thumbs/page-042.jpg Why does quartz grow pointy tips? Quartz crystals often grow from the wall of a cavity or crack, with their base stuck to the rock and the other end free in open space. Only the free end can grow neat, sloped faces that meet in a point. The attached end has nowhere to grow and stays rough. Many quartz crystals look like six-sided columns topped with a pointed pyramid. https://socialmedia.xdme.com/tony/videos-book27/page-042.mp4 https://www.youtube.com/embed/jcXVj_4-i0s 105 2026-10-09T14:44:23+00:00 yes https://xdme.com/watch-book27-q043.html https://xdme.com/book27-thumbs/page-043.jpg Why do some crystals have stripes or bands? As a crystal grows layer by layer, conditions around it may change: the temperature, the amount of dissolved minerals, or tiny impurities such as iron. Each change can leave a colored band. These are called growth bands, a bit like tree rings. Agate, a type of quartz, shows beautiful curved stripes inside, and some amethyst crystals have color zones. https://socialmedia.xdme.com/tony/videos-book27/page-043.mp4 https://www.youtube.com/embed/Hl-MdCHEY_c 111 2026-10-09T14:44:24+00:00 yes https://xdme.com/watch-book27-q044.html https://xdme.com/book27-thumbs/page-044.jpg Why do crystals grow in clusters? In a mineral-rich liquid, many tiny crystals often start at the same time across a surface. They grow side by side, competing for space, and the ones that point outward keep growing while others are blocked. This makes a cluster of crystal points, like a crowd of people leaning in. You can see this in cut geodes and in sparkling mineral clusters displayed in museums. https://socialmedia.xdme.com/tony/videos-book27/page-044.mp4 https://www.youtube.com/embed/Csp2vlnre3w 109 2026-10-09T14:44:25+00:00 yes https://xdme.com/watch-book27-q045.html https://xdme.com/book27-thumbs/page-045.jpg What is a desert rose? A desert rose is a cluster of flat crystals, usually gypsum or barite, that looks like the petals of a rose. It forms in dry, sandy soil when salty groundwater slowly seeps through the sand and crystals grow between the grains, trapping sand inside. The crystals fan out in a rosette. Desert roses are found in dry places such as Sahara in Africa and parts of North America. https://socialmedia.xdme.com/tony/videos-book27/page-045.mp4 https://www.youtube.com/embed/WlClTfoc6Lc 106 2026-10-09T14:44:26+00:00 yes https://xdme.com/watch-book27-q046.html https://xdme.com/book27-thumbs/page-046.jpg How do scientists grow big, perfect crystals in a lab? Scientists give crystals the conditions they love: very clean liquids, a seed crystal, and slow, steady changes in temperature. To make the silicon crystals used for computer chips, a seed crystal is dipped into hot liquid silicon and slowly pulled up while turning. The silicon freezes onto it, growing a long, smooth cylinder. The process can take days and must be extremely precise. https://socialmedia.xdme.com/tony/videos-book27/page-046.mp4 https://www.youtube.com/embed/5L4J5wkhhKU 110 2026-10-09T14:44:28+00:00 yes https://xdme.com/watch-book27-q047.html https://xdme.com/book27-thumbs/page-047.jpg Why do crystals grow on a string or twig? A rough surface, like fuzzy string or a twig, gives dissolved particles many tiny places to start sticking. As the liquid evaporates or cools, particles attach there and grow. That is why a string dipped in sugar water collects rock candy crystals. In nature, minerals from springs can coat leaves and twigs with crystals the same way. https://socialmedia.xdme.com/tony/videos-book27/page-047.mp4 https://www.youtube.com/embed/_68w7hbADts 107 2026-10-09T14:44:29+00:00 yes https://xdme.com/watch-book27-q048.html https://xdme.com/book27-thumbs/page-048.jpg Why do taps and glasses get white crusty spots? Tap water carries dissolved minerals such as calcium. When drops dry, the water evaporates and the minerals stay behind as a hard, white crust of tiny crystals called scale. Some areas have harder water with more minerals, so spots are bigger. Ask a grown-up to clean with a safe cleaner, since some can irritate skin or eyes. https://socialmedia.xdme.com/tony/videos-book27/page-048.mp4 https://www.youtube.com/embed/3Xsrgalje38 110 2026-10-09T14:44:31+00:00 yes https://xdme.com/watch-book27-q049.html https://xdme.com/book27-thumbs/page-049.jpg Can a chipped crystal heal itself? Sometimes, yes. If a crystal with a chipped corner is placed back in a solution that is full of its dissolved material, atoms attach first at the damaged spot, because it offers many places to stick. Over time, the crystal can regrow its original shape. Scientists in the 1800s noticed this and learned that crystals prefer to return to their natural forms. https://socialmedia.xdme.com/tony/videos-book27/page-049.mp4 https://www.youtube.com/embed/Lz-uw67jCnc 107 2026-10-09T14:44:32+00:00 yes https://xdme.com/watch-book27-q050.html https://xdme.com/book27-thumbs/page-050.jpg What are the secrets to growing a great crystal? Use clean containers, pure ingredients, and a good seed. Keep the setup still, away from drafts and bumps. Make changes slowly, such as letting water evaporate over days. Be patient, because rushing leads to cloudy clumps. Take notes on what you tried and how it looked. Like any science project, trying the same thing again with one small change teaches the most. https://socialmedia.xdme.com/tony/videos-book27/page-050.mp4 https://www.youtube.com/embed/KPawA9LzM0c 110 2026-10-09T14:44:33+00:00 yes https://xdme.com/watch-book27-q051.html https://xdme.com/book27-thumbs/page-051.jpg Why are there so many kinds of sugar if they are all crystals? Sugar is made of crystals, and different sugars are just crystals of different sizes. Granulated sugar has small grains, powdered sugar is ground very fine, and sanding sugar has big, sparkly crystals for decorating cookies. Brown sugar has a thin coat of molasses on each crystal, which makes it moist and darker. Sugar cubes are crystals pressed together. Each kind is useful in a different recipe. https://socialmedia.xdme.com/tony/videos-book27/page-051.mp4 https://www.youtube.com/embed/pRUSVxend3Q 109 2026-10-09T14:44:34+00:00 yes https://xdme.com/watch-book27-q052.html https://xdme.com/book27-thumbs/page-052.jpg Why does chocolate have to be tempered to snap? Chocolate gets its snap and shine from the fat in cocoa butter, which can form crystals in several different ways. Chocolate makers carefully warm and cool the chocolate so only the best kind of tiny crystals form. These stable crystals make it glossy, crisp, and melt-in-your-mouth at body temperature. Without this step, chocolate can be dull, crumbly, or soft. https://socialmedia.xdme.com/tony/videos-book27/page-052.mp4 https://www.youtube.com/embed/17xOZBZKeFg 109 2026-10-09T14:44:36+00:00 yes https://xdme.com/watch-book27-q053.html https://xdme.com/book27-thumbs/page-053.jpg Why does thawed and refrozen ice cream get gritty? Good ice cream is full of very tiny ice crystals, which feel smooth on your tongue. When ice cream warms and freezes again, the small crystals melt and join into larger ones that feel gritty. Ice cream makers keep crystals tiny by freezing the mix while churning it, and by adding fats, sugar, and air that get in the way of crystal growth. https://socialmedia.xdme.com/tony/videos-book27/page-053.mp4 https://www.youtube.com/embed/f0Sh1L_EHWw 107 2026-10-09T14:44:37+00:00 yes https://xdme.com/watch-book27-q054.html https://xdme.com/book27-thumbs/page-054.jpg Why is fudge smooth but rock candy crunchy? Both are sugar crystals, but they are different sizes. Rock candy forms slowly and grows large crystals you can crunch. Fudge makers cool the hot candy mixture and then beat it, which starts millions of tiny crystals that are too small to feel, so it is smooth. The size of the crystals decides the texture. Cooking hot sugar is for grown-ups only. https://socialmedia.xdme.com/tony/videos-book27/page-054.mp4 https://www.youtube.com/embed/uE1C9nIp0qI 109 2026-10-09T14:44:38+00:00 yes https://xdme.com/watch-book27-q055.html https://xdme.com/book27-thumbs/page-055.jpg How does maple syrup turn into maple sugar? Maple trees give sap that is mostly water. Syrup makers boil it down until it is thick, taking about forty buckets of sap for one of syrup. If the syrup is heated more and stirred, the sugar starts forming tiny crystals, making maple sugar or soft maple butter. Canada makes most of the world's maple syrup, and Quebec makes the most of all. https://socialmedia.xdme.com/tony/videos-book27/page-055.mp4 https://www.youtube.com/embed/WSTdOseooDk 107 2026-10-09T14:44:39+00:00 yes https://xdme.com/watch-book27-q056.html https://xdme.com/book27-thumbs/page-056.jpg What are the crunchy bits in aged cheese? Old cheeses like Parmesan, aged cheddar, and aged Gouda often have little crunchy specks. These are tiny crystals that grow slowly while cheese ages. Some are made of an amino acid called tyrosine, and others are calcium lactate. They are harmless, and many cheese lovers think they are a sign of a well-aged cheese. Crunchy crystals show that slow growth takes time. https://socialmedia.xdme.com/tony/videos-book27/page-056.mp4 https://www.youtube.com/embed/4Ty2vSZajL0 103 2026-10-09T14:44:39+00:00 yes https://xdme.com/watch-book27-q057.html https://xdme.com/book27-thumbs/page-057.jpg Why does salt clump up in the shaker on damp days? Salt crystals attract a little moisture from humid air. The thin film of water lets salt grains stick together, and when it dries, little crystal bridges form that glue them into lumps. Makers often add an anti-caking ingredient that soaks up moisture. Many people drop a few grains of rice into a shaker, since rice absorbs extra moisture too. https://socialmedia.xdme.com/tony/videos-book27/page-057.mp4 https://www.youtube.com/embed/buELscQ7O5g 105 2026-10-09T14:44:41+00:00 yes https://xdme.com/watch-book27-q058.html https://xdme.com/book27-thumbs/page-058.jpg Why do some salts look like flakes or pyramids? When salt crystallizes from a quickly evaporating pool of brine, crystals start on the surface and grow outward into hollow pyramids that float. They are called flake salt and are light and crunchy. Table salt grows in tanks and has dense little cubes. The shape depends on how and where the crystals grow. Cooks like flakes for a crunchy finish on food. https://socialmedia.xdme.com/tony/videos-book27/page-058.mp4 https://www.youtube.com/embed/0cYbVnneBEA 107 2026-10-09T14:44:42+00:00 yes https://xdme.com/watch-book27-q059.html https://xdme.com/book27-thumbs/page-059.jpg Why does cold grape juice sometimes have tiny crystals? Grape juice contains natural substances such as tartaric acid and potassium. In the cold, they can combine into small crystals called tartrates, which settle at the bottom or stick to the cork. They look like sand or glass bits but are harmless. They are the same stuff as cream of tartar, used in baking. Juice makers sometimes chill and filter juice to remove them. https://socialmedia.xdme.com/tony/videos-book27/page-059.mp4 https://www.youtube.com/embed/6a1ZZEFf1-8 106 2026-10-09T14:44:43+00:00 yes https://xdme.com/watch-book27-q060.html https://xdme.com/book27-thumbs/page-060.jpg What is Epsom salt? Epsom salt is not table salt. It is magnesium sulfate, a mineral that forms clear, needle-like crystals. It was first found in 1618 in the water of a spring near Epsom, England. People use it in baths, in gardens, and for science projects because it dissolves easily and makes beautiful crystals. It is not for eating, so never taste it. https://socialmedia.xdme.com/tony/videos-book27/page-060.mp4 https://www.youtube.com/embed/sV0u0o7kOpY 110 2026-10-09T14:44:44+00:00 yes https://xdme.com/watch-book27-q061.html https://xdme.com/book27-thumbs/page-061.jpg Is cotton candy made of sugar crystals? Not really. A cotton candy machine melts sugar and flings it through tiny holes in a spinning bowl. The thin threads cool so fast that the sugar atoms freeze in a jumble instead of lining up, making a glassy solid, like window glass. On a damp day, the threads soak up moisture, shrink, and can turn into crystals. The hot machine is for adults to run. https://socialmedia.xdme.com/tony/videos-book27/page-061.mp4 https://www.youtube.com/embed/NKE2bQsOqyA 106 2026-10-09T14:44:45+00:00 yes https://xdme.com/watch-book27-q062.html https://xdme.com/book27-thumbs/page-062.jpg What is freezer burn? Freezer burn happens when frozen food loses moisture. Water slowly turns from ice straight into vapor and escapes from the food, then re-freezes as frosty crystals inside the package. The food becomes dry, pale, and tough in spots. It is not dangerous, but it doesn't taste as good. Wrapping food tightly and removing air keeps crystals from forming. https://socialmedia.xdme.com/tony/videos-book27/page-062.mp4 https://www.youtube.com/embed/93TaQ2bGEbE 109 2026-10-09T14:55:18+00:00 yes https://xdme.com/watch-book27-q063.html https://xdme.com/book27-thumbs/page-063.jpg What is table salt made of, and why does it look like tiny cubes? Table salt is made of sodium and chloride, joined as sodium chloride. In a crystal, sodium and chloride alternate in a cube-shaped lattice, like a three-dimensional checkerboard. As the crystals grow, their outer faces form flat squares, so each grain is a tiny cube. This is why salt crumbles into smaller cubes. Salt is safe in food. https://socialmedia.xdme.com/tony/videos-book27/page-063.mp4 https://www.youtube.com/embed/d6Gm7kaVA1A 108 2026-10-09T14:58:39+00:00 yes https://xdme.com/watch-book27-q064.html https://xdme.com/book27-thumbs/page-064.jpg Why do dried juice spills feel gritty? Juice is mostly water with sugar dissolved in it. When the water evaporates, the sugar can no longer stay dissolved, so it forms tiny crystals. At first the spill feels sticky because of the thick syrup. As it dries, the crystals become hard and gritty. Wiping up spills with a damp cloth dissolves the sugar again and takes it away. https://socialmedia.xdme.com/tony/videos-book27/page-064.mp4 https://www.youtube.com/embed/-Sq9OklCLdo 103 2026-10-09T15:02:28+00:00 yes https://xdme.com/watch-book27-q065.html https://xdme.com/book27-thumbs/page-065.jpg How does a reusable hand warmer get hot when you click it? Inside the pouch is a liquid called sodium acetate, which is kept liquid even though it is below the temperature at which it would normally crystallize. Clicking a small metal disc starts crystals growing, and they spread quickly through the liquid. As the atoms lock into place, they let out heat, making the pouch warm. A grown-up must boil it again to reset it. https://socialmedia.xdme.com/tony/videos-book27/page-065.mp4 https://www.youtube.com/embed/BWd4L9S8jh0 110 2026-10-09T15:06:03+00:00 yes https://xdme.com/watch-book27-q066.html https://xdme.com/book27-thumbs/page-066.jpg Why do white fluffy crystals grow on brick walls? Bricks and concrete hold tiny amounts of salts. When water seeps through the wall, it dissolves some salt. At the surface, the water evaporates and leaves the salt behind as a white, fluffy coating of crystals. This is called efflorescence. It's harmless but tells builders that moisture is moving through the wall. It can be brushed off when dry. https://socialmedia.xdme.com/tony/videos-book27/page-066.mp4 https://www.youtube.com/embed/04HFHzcse4A 105 2026-10-09T15:10:34+00:00 yes https://xdme.com/watch-book27-q067.html https://xdme.com/book27-thumbs/page-067.jpg How do factories turn sugar juice into crystals? Sugar comes from sugar cane or sugar beets. Factories squeeze out the sweet juice, clean it, and boil it under low pressure so it thickens at gentler temperatures. They add tiny seed crystals so sugar grows on them. A spinning machine then flings off the syrup and leaves clean crystals. In Canada, sugar beets are grown in parts of Alberta, and cane sugar is refined in cities such as Toronto. https://socialmedia.xdme.com/tony/videos-book27/page-067.mp4 https://www.youtube.com/embed/s7j6As3LAGM 106 2026-10-09T15:15:07+00:00 yes https://xdme.com/watch-book27-q068.html https://xdme.com/book27-thumbs/page-068.jpg Why do cooks worry about stray sugar crystals in caramel? When sugar is melted into caramel, one stray crystal on the side of the pot can fall in and start a chain reaction. The liquid turns grainy and cloudy as crystals grow everywhere. Cooks avoid this by keeping the sides clean, using a lid, or adding a little acid or syrup that gets in the way. Making caramel involves very hot sugar, so it's a job for grown-ups. https://socialmedia.xdme.com/tony/videos-book27/page-068.mp4 https://www.youtube.com/embed/cZr8CEqoVRY 107 2026-10-09T15:20:10+00:00 yes https://xdme.com/watch-book27-q069.html https://xdme.com/book27-thumbs/page-069.jpg Why is butter hard in the fridge but soft on the counter? Butter contains fat that forms tiny crystals when it is cold. The crystals interlock like a mesh and make butter firm. As it warms, some of these crystals melt, so the butter becomes softer and spreadable. Butter doesn't melt all at once because it holds different kinds of fat crystals, which melt at different temperatures. That's why it goes slowly from hard to soft to liquid. https://socialmedia.xdme.com/tony/videos-book27/page-069.mp4 https://www.youtube.com/embed/Oeo_PKhR-3s 104 2026-10-09T15:24:43+00:00 yes https://xdme.com/watch-book27-q070.html https://xdme.com/book27-thumbs/page-070.jpg Why does old hard candy turn cloudy and sticky? Fresh hard candy is sugar glass: the sugar was melted and cooled so fast that it never formed crystals. Sugar likes water, so in humid air the candy’s surface soaks up moisture and turns sticky. Then the sugar molecules can move around and begin lining up into tiny crystals, which make the candy look cloudy and grainy. A tightly wrapped candy stays clear and glassy for much longer. https://socialmedia.xdme.com/tony/videos-book27/page-070.mp4 https://www.youtube.com/embed/FRsU0VgGTZg 106 2026-10-09T15:29:45+00:00 yes https://xdme.com/watch-book27-q071.html https://xdme.com/book27-thumbs/page-071.jpg Why does old chocolate get a white film? A white, powdery film on chocolate is called bloom. Fat bloom happens when heat changes make some cocoa butter melt and then form new crystals on the surface. Sugar bloom happens when moisture dissolves surface sugar, which dries as tiny crystals. Chocolate with bloom is safe to eat but looks pale and may feel gritty. Storing it in a cool, dry place helps prevent it. https://socialmedia.xdme.com/tony/videos-book27/page-071.mp4 https://www.youtube.com/embed/upRhBy6V7XE 102 2026-10-09T15:34:18+00:00 yes https://xdme.com/watch-book27-q072.html https://xdme.com/book27-thumbs/page-072.jpg How can you tell salt from sugar without tasting? Never taste an unknown white powder! Instead, use your eyes. Spread a few grains on dark paper and use a magnifier. Salt grains are tiny, clear cubes with sharp corners. Sugar crystals are slightly bigger and more irregular, with shiny, sparkling faces. Scientists identify things by looking at their shape, color, and other properties before ever tasting. https://socialmedia.xdme.com/tony/videos-book27/page-072.mp4 https://www.youtube.com/embed/xKhkTOSspaM 109 2026-10-09T15:39:20+00:00 yes https://xdme.com/watch-book27-q073.html https://xdme.com/book27-thumbs/page-073.jpg Why do grains of beach sand flash in the light? Most beach and playground sand is full of quartz grains, which are tiny crystals with shiny faces. When sunlight hits them, flat faces reflect light like tiny mirrors. Some sand also contains flakes of mica, which flash and shimmer. Sand can also hold bits of shell, rock, and volcanic glass, so every beach has its own mix. A magnifier shows a treasure chest. https://socialmedia.xdme.com/tony/videos-book27/page-073.mp4 https://www.youtube.com/embed/4KMT1_oF1kk 107 2026-10-09T15:43:53+00:00 yes https://xdme.com/watch-book27-q074.html https://xdme.com/book27-thumbs/page-074.jpg What is the crusty white stuff on old batteries? When an old alkaline battery leaks, the liquid inside reacts with air and dries into crusty white crystals. The crystals can irritate skin and eyes. If you ever see white crust on a battery, do not touch it. Tell a grown-up, who can wear gloves, remove it, and dispose of the battery properly. Taking batteries out of devices that are not used for a long time prevents leaks. https://socialmedia.xdme.com/tony/videos-book27/page-074.mp4 https://www.youtube.com/embed/FnEAe4bsDyU 106 2026-10-09T15:48:55+00:00 yes https://xdme.com/watch-book27-q075.html https://xdme.com/book27-thumbs/page-075.jpg How can you explore crystals safely at your own kitchen table? Set up a tray, a magnifier, dark paper, and a few safe ingredients such as salt, sugar, and Epsom salt. Look at them closely and draw what you see. Try dissolving them in warm tap water and letting drops dry. Don't taste experiments, don't use hot liquids by yourself, and wash your hands after. With a little care, a kitchen is a great crystal lab. https://socialmedia.xdme.com/tony/videos-book27/page-075.mp4 https://www.youtube.com/embed/hpUWkRncV6A 111 2026-10-09T15:53:27+00:00 yes https://xdme.com/watch-book27-q076.html https://xdme.com/book27-thumbs/page-076.jpg What makes a mineral a gemstone? A gemstone is a mineral, or sometimes another natural material, that is beautiful, tough enough to wear, and rare enough to be valued. Diamonds, rubies, sapphires, and emeralds are well-known examples. Most gems start as rough stones that look dull until a gem cutter shapes and polishes them. A gem's color, clarity, and hardness all help decide how special it is. https://socialmedia.xdme.com/tony/videos-book27/page-076.mp4 https://www.youtube.com/embed/e64tfU0lfmY 115 2026-10-09T14:44:46+00:00 yes https://xdme.com/watch-book27-q077.html https://xdme.com/book27-thumbs/page-077.jpg What is the Mohs scale? In 1812, German scientist Friedrich Mohs made a ranking of minerals by how hard they are. It runs from 1, soft talc, up to 10, diamond. A harder mineral can scratch a softer one but not the other way around. The scale is not evenly spaced, but it is a handy way to compare minerals. Quartz is a 7, and gypsum is a 2. https://socialmedia.xdme.com/tony/videos-book27/page-077.mp4 https://www.youtube.com/embed/0qUR2vNt6IY 110 2026-10-09T14:44:47+00:00 yes https://xdme.com/watch-book27-q078.html https://xdme.com/book27-thumbs/page-078.jpg How can you test how hard a mineral is? Try scratching it with common items. A fingernail is about 2.5 on the Mohs scale, a copper coin about 3.5, a steel nail about 5.5, and a piece of window glass about 5.5. If your fingernail can scratch it, it's softer than that. If a nail scratches it but a coin can't, it's in the middle. Always scratch gently, and let a grown-up handle glass. https://socialmedia.xdme.com/tony/videos-book27/page-078.mp4 https://www.youtube.com/embed/OI-_8u9gMho 116 2026-10-09T14:44:48+00:00 yes https://xdme.com/watch-book27-q079.html https://xdme.com/book27-thumbs/page-079.jpg What is a streak test? A streak test rubs a mineral across a rough, white, unglazed porcelain tile to leave a line of powder. The color of the powder can be different from the color of the mineral. Hematite looks silver or black but leaves a reddish-brown streak, and pyrite leaves a greenish-black one. Streak color is often more reliable than the outside color for identifying minerals. https://socialmedia.xdme.com/tony/videos-book27/page-079.mp4 https://www.youtube.com/embed/7mGnMb3OwTI 107 2026-10-09T14:44:49+00:00 yes https://xdme.com/watch-book27-q080.html https://xdme.com/book27-thumbs/page-080.jpg How does a mineral's shine help you name it? Luster describes how a mineral looks when light bounces off its surface. Metallic luster shines like metal, as in pyrite. Glassy luster looks like glass, as in quartz. Others look pearly, silky, waxy, or dull and earthy. Luster is one of the first clues rock detectives use, because you can notice it without any tools. Try tilting a stone under a lamp to see how the light moves. https://socialmedia.xdme.com/tony/videos-book27/page-080.mp4 https://www.youtube.com/embed/XqbVXQ7ixKs 108 2026-10-09T14:44:50+00:00 yes https://xdme.com/watch-book27-q081.html https://xdme.com/book27-thumbs/page-081.jpg Why do some rocks feel heavy for their size? Different minerals pack different numbers of atoms and heavier atoms into the same space, which makes them dense. Galena, a lead mineral, feels much heavier than quartz of the same size. Gold is even heavier. Comparing how heavy a sample feels, called heft, is a quick test. Scientists measure it as density or specific gravity by comparing the sample's weight with the same amount of water. https://socialmedia.xdme.com/tony/videos-book27/page-081.mp4 https://www.youtube.com/embed/F6JIhjj2K8U 106 2026-10-09T14:51:22+00:00 yes https://xdme.com/watch-book27-q082.html https://xdme.com/book27-thumbs/page-082.jpg Why is a ruby red and a sapphire blue if both are the same mineral? Rubies and sapphires are both made of corundum, a very hard mineral made of aluminum and oxygen. Pure corundum is clear. A tiny bit of chromium turns it red and makes a ruby, while traces of iron and titanium make it blue. Sapphires can also be yellow, pink, or green. Small amounts of other elements can make a big difference in color. https://socialmedia.xdme.com/tony/videos-book27/page-082.mp4 https://www.youtube.com/embed/ZA9Lgj0pyvg 106 2026-10-09T14:51:23+00:00 yes https://xdme.com/watch-book27-q083.html https://xdme.com/book27-thumbs/page-083.jpg What makes an opal flash rainbow colors? Opal is made of tiny silica spheres stacked in neat layers, with water in between. When light enters, the layers bend it and split it into colors, creating flashes that change as you turn the stone. This is called play of color. Opals aren't true crystals because their pattern is not completely regular, but they shimmer. Much of the world's opal is found in Australia. https://socialmedia.xdme.com/tony/videos-book27/page-083.mp4 https://www.youtube.com/embed/U7ORWfo_QQo 106 2026-10-09T14:51:24+00:00 yes https://xdme.com/watch-book27-q084.html https://xdme.com/book27-thumbs/page-084.jpg How do gem cutters turn rough stones into gems? A gem cutter, or lapidary, studies a rough stone to find the best shape. The stone is sawed, ground, and polished using grit made of very hard materials such as diamond dust. Flat faces called facets are cut at exact angles so light bounces inside and flashes out. Some stones are polished smooth into domes called cabochons. Cutters work with water and masks to stay safe. https://socialmedia.xdme.com/tony/videos-book27/page-084.mp4 https://www.youtube.com/embed/bUepG6IXkIM 109 2026-10-09T14:51:25+00:00 yes https://xdme.com/watch-book27-q085.html https://xdme.com/book27-thumbs/page-085.jpg What is a lab-grown diamond? A lab-grown diamond is a real diamond made by people. Scientists put a tiny diamond seed in a chamber and either squeeze carbon at very high pressure and temperature or grow it from a hot carbon gas, layer by layer. After days or weeks, the seed has grown into a larger crystal. It has the same atoms and structure as a mined one. Lab diamonds are also used in tools. https://socialmedia.xdme.com/tony/videos-book27/page-085.mp4 https://www.youtube.com/embed/x9Yq-LAcYDs 103 2026-10-09T14:51:27+00:00 yes https://xdme.com/watch-book27-q086.html https://xdme.com/book27-thumbs/page-086.jpg What are the crystal patterns inside some meteorites? Some iron meteorites are pieces of the cores of ancient broken asteroids. When a slice is cut, polished, and dipped in mild acid by a lab, a crisscross pattern appears, called a Widmanstätten pattern. It is made of crystals of two kinds of iron and nickel that formed as the metal cooled incredibly slowly in space, over millions of years. This pattern can't be made on Earth. https://socialmedia.xdme.com/tony/videos-book27/page-086.mp4 https://www.youtube.com/embed/qxynLVHGUcY 112 2026-10-09T14:51:28+00:00 yes https://xdme.com/watch-book27-q087.html https://xdme.com/book27-thumbs/page-087.jpg Why do some minerals glow under a special lamp? Some minerals soak up invisible ultraviolet light and give back some of the energy as visible light, so they glow bright red, green, or blue. This is called fluorescence. Fluorite is such a mineral, and it gave the effect its name. Scientists and museums use UV lamps in dark rooms to show glowing rocks. Never shine a UV lamp toward anyone's eyes. https://socialmedia.xdme.com/tony/videos-book27/page-087.mp4 https://www.youtube.com/embed/s3cjUsOJFWY 107 2026-10-09T14:51:29+00:00 yes https://xdme.com/watch-book27-q088.html https://xdme.com/book27-thumbs/page-088.jpg How can you tell fool's gold from real gold? Pyrite, called fool's gold, shines like brassy gold but is a different mineral. Real gold is soft enough to dent with a nail, while pyrite is hard and brittle, and may form tiny cubes. Gold leaves a yellow streak, and pyrite leaves a greenish-black one. Gold is also much heavier for its size. Rock hounds use these tests to avoid being fooled. https://socialmedia.xdme.com/tony/videos-book27/page-088.mp4 https://www.youtube.com/embed/dOq-lPU5Z2w 110 2026-10-09T14:51:29+00:00 yes https://xdme.com/watch-book27-q089.html https://xdme.com/book27-thumbs/page-089.jpg What gems and minerals come from Canada? Canada has many treasures. Amethyst is mined near Thunder Bay, Ontario, and is Ontario's gemstone. Diamonds are mined in the Northwest Territories and other northern areas. Alberta has ammolite, a rainbow gem formed from fossil shells. Labrador has labradorite, a stone that flashes blue in the light. Every province has its own minerals worth exploring. https://socialmedia.xdme.com/tony/videos-book27/page-089.mp4 https://www.youtube.com/embed/K-_uZgGY-Mk 115 2026-10-09T14:51:31+00:00 yes https://xdme.com/watch-book27-q090.html https://xdme.com/book27-thumbs/page-090.jpg What is a rock hound? A rock hound is someone who loves finding and collecting rocks, minerals, and crystals. Rock hounds explore creeks and beaches where collecting is allowed. They learn to identify what they find by color, hardness, shine, and shape. Quarries and road cuts can be dangerous, so rock hounds visit them only on permitted trips with an adult. A notebook, a bag, and a curious mind are enough to start. https://socialmedia.xdme.com/tony/videos-book27/page-090.mp4 https://www.youtube.com/embed/wvuqYExWAMo 111 2026-10-09T14:51:33+00:00 yes https://xdme.com/watch-book27-q091.html https://xdme.com/book27-thumbs/page-091.jpg What gear does a young rock hound need? Basic gear includes safety glasses, sturdy shoes, gloves for scratchy rocks, a magnifying lens, a notebook and pencil, small bags, and newspapers to wrap fragile finds. A grown-up should handle any hammer or chisel, and everyone nearby needs eye protection when rocks are split because chips can fly. Bring water and a snack, and watch for slippery or steep places. https://socialmedia.xdme.com/tony/videos-book27/page-091.mp4 https://www.youtube.com/embed/vVn17M3z4Ns 108 2026-10-09T14:51:34+00:00 yes https://xdme.com/watch-book27-q092.html https://xdme.com/book27-thumbs/page-092.jpg Why do rock hounds follow collecting rules? Places like national and provincial parks usually protect rocks, fossils, and plants, so taking them is not allowed. On private land you must ask the owner first. Rules protect special places so everyone can enjoy them and scientists can study them. A good rock hound leaves the area as tidy as they found it, stays away from cliffs, and takes only what is permitted. https://socialmedia.xdme.com/tony/videos-book27/page-092.mp4 https://www.youtube.com/embed/lkXJV5Kr4yw 107 2026-10-09T14:51:35+00:00 yes https://xdme.com/watch-book27-q093.html https://xdme.com/book27-thumbs/page-093.jpg How do you label and keep a rock collection? Give every specimen a number and write it on a small sticker or tag. In a notebook, record the date, where you found it, and what it looks like. The place where it was found is the most important clue. Store samples in egg cartons or small boxes with soft paper. Take pictures. A well-labeled collection can be used to learn and share science. https://socialmedia.xdme.com/tony/videos-book27/page-093.mp4 https://www.youtube.com/embed/mDTlaTZU8MA 104 2026-10-09T14:51:36+00:00 yes https://xdme.com/watch-book27-q094.html https://xdme.com/book27-thumbs/page-094.jpg Where can you see amazing minerals in a museum? Museums keep huge collections of minerals, gems, and meteorites that you can study up close. The Royal Ontario Museum in Toronto has a large gallery of minerals and gemstones, including crystals, gems, and meteorites. Other science museums across Canada have rock and fossil displays. Seeing rare specimens helps rock hounds learn what to look for in the field. https://socialmedia.xdme.com/tony/videos-book27/page-094.mp4 https://www.youtube.com/embed/7G61RNgR6ec 117 2026-10-09T14:51:37+00:00 yes https://xdme.com/watch-book27-q095.html https://xdme.com/book27-thumbs/page-095.jpg How can you tell quartz from calcite? They can look alike, but they behave differently. Quartz is harder: it scratches glass and rates a 7. Calcite is softer, about 3, and can be scratched by a copper coin. Quartz breaks in smooth, curved pieces, while calcite splits into slanted blocks. A grown-up can also drip a little vinegar on calcite, which will fizz, but quartz doesn't react. https://socialmedia.xdme.com/tony/videos-book27/page-095.mp4 https://www.youtube.com/embed/pP4jcvPNSGo 110 2026-10-09T14:51:38+00:00 yes https://xdme.com/watch-book27-q096.html https://xdme.com/book27-thumbs/page-096.jpg How does a rock tumbler make stones shiny? A rock tumbler is a rotating barrel filled with rough stones, water, and gritty powder. As the barrel turns for days or weeks, the stones rub against the grit and each other, wearing off rough spots. Coarse grit comes first, then finer grits, and finally a polishing powder. The stones come out smooth and shiny. It is noisy, so it's best to run it in a garage. https://socialmedia.xdme.com/tony/videos-book27/page-096.mp4 https://www.youtube.com/embed/MRQ_D43j7MQ 109 2026-10-09T14:51:39+00:00 yes https://xdme.com/watch-book27-q097.html https://xdme.com/book27-thumbs/page-097.jpg What everyday things are made from minerals? Minerals are in many things around you. Table salt is a mineral called halite. Drywall is made from gypsum. Glass is made from quartz sand. Pencils use graphite. Baby powder is made of talc. Aluminum cans come from a rock called bauxite. Phones need minerals for their metals and parts. Without minerals, we wouldn't have buildings, tools, or computers. https://socialmedia.xdme.com/tony/videos-book27/page-097.mp4 https://www.youtube.com/embed/KBJIpK7CiKA 111 2026-10-09T14:51:40+00:00 yes https://xdme.com/watch-book27-q098.html https://xdme.com/book27-thumbs/page-098.jpg What is mica, and why does it peel into thin sheets? Mica is a shiny mineral made of stacked flat layers. The layers are held together only weakly, so you can peel them apart into thin, flexible, transparent sheets. Mica handles heat well and does not conduct electricity, which made it useful for old oven windows and electronics. Powdered mica puts a shimmer in some paints and makeup. In the sand, you may see small flashing flakes of it. https://socialmedia.xdme.com/tony/videos-book27/page-098.mp4 https://www.youtube.com/embed/Gh-9EPxW4R8 107 2026-10-09T14:51:41+00:00 yes https://xdme.com/watch-book27-q099.html https://xdme.com/book27-thumbs/page-099.jpg Do amateur collectors ever discover new minerals? Yes! Scientists approve about a hundred new minerals each year, and some were first noticed by amateur collectors who spotted something unusual. They share it with experts, who test it in a lab. If it has a new combination of chemistry and structure, it can get a new name. Careful notes and curiosity matter more than expensive tools. https://socialmedia.xdme.com/tony/videos-book27/page-099.mp4 https://www.youtube.com/embed/uAiRo-qS7dc 107 2026-10-09T14:55:19+00:00 yes https://xdme.com/watch-book27-q100.html https://xdme.com/book27-thumbs/page-100.jpg Can a mineral's color fool you? Yes. The same mineral can come in many colors: quartz can be purple, pink, yellow, smoky brown, or clear. Impurities cause the changes. And different minerals can share the same color, like green malachite and green emerald. That is why mineral detectives also test streak, hardness, shine, and shape. Color is a clue, but never the whole story. https://socialmedia.xdme.com/tony/videos-book27/page-100.mp4 https://www.youtube.com/embed/qMmayolVtQM 110 2026-10-09T14:55:20+00:00 yes https://xdme.com/watch-book27-q101.html https://xdme.com/book27-thumbs/page-101.jpg How does a quartz crystal keep a watch on time? Inside a quartz watch is a tiny slice of quartz shaped like a tuning fork. A battery sends electricity through it, which makes it vibrate 32,768 times every second. A small circuit counts those vibrations and turns them into one tick each second. Because the crystal vibrates so steadily, a quartz watch may drift only a few seconds in a month. https://socialmedia.xdme.com/tony/videos-book27/page-101.mp4 https://www.youtube.com/embed/f3YVmOiyepc 116 2026-10-09T14:55:21+00:00 yes https://xdme.com/watch-book27-q102.html https://xdme.com/book27-thumbs/page-102.jpg What is the piezoelectric effect? Some crystals, like quartz, make a small electric voltage when they are pressed or bent. Scientists call this the piezoelectric effect, from a Greek word for press. Pierre and Jacques Curie discovered it in 1880. It also works in reverse: electricity makes the crystal change shape slightly. This two-way trick lets crystals sense pressure, make sound, and keep time. https://socialmedia.xdme.com/tony/videos-book27/page-102.mp4 https://www.youtube.com/embed/8nPLKgK3VMk 114 2026-10-09T14:55:21+00:00 yes https://xdme.com/watch-book27-q103.html https://xdme.com/book27-thumbs/page-103.jpg How does a click-on barbecue lighter make a spark? When you push the button on some lighters, a spring-loaded hammer snaps against a small piezoelectric crystal. The sudden squeeze makes a high voltage that jumps across a tiny gap as a spark, lighting the gas. No battery is needed. These lighters and stove igniters are for grown-ups only, since they start fires. https://socialmedia.xdme.com/tony/videos-book27/page-103.mp4 https://www.youtube.com/embed/QtdNnUV4e2s 108 2026-10-09T14:55:22+00:00 yes https://xdme.com/watch-book27-q104.html https://xdme.com/book27-thumbs/page-104.jpg How do tiny crystals make buzzers and beeps? Many beeping alarms use a thin disc with a piezoelectric crystal on it. When electricity flows in a pulsing pattern, the disc flexes back and forth quickly, pushing the air and making sound. Smoke alarms, microwave ovens, and greeting cards use these buzzers because they are cheap, small, and need little power. Changing how fast the electricity pulses changes the pitch. https://socialmedia.xdme.com/tony/videos-book27/page-104.mp4 https://www.youtube.com/embed/wo048ont7oQ 111 2026-10-09T14:55:23+00:00 yes https://xdme.com/watch-book27-q105.html https://xdme.com/book27-thumbs/page-105.jpg Why do computer chips use silicon crystals? Silicon is a semiconductor, a material that can switch between letting electricity flow and blocking it, which is just what a computer needs. It is also one of the most common elements in Earth's crust. For chips, silicon must form a nearly perfect single crystal, because even tiny flaws can break a circuit. This is why chip factories are cleaner than hospitals. https://socialmedia.xdme.com/tony/videos-book27/page-105.mp4 https://www.youtube.com/embed/Fh-ctVTI_FM 112 2026-10-09T14:55:24+00:00 yes https://xdme.com/watch-book27-q106.html https://xdme.com/book27-thumbs/page-106.jpg How is sand turned into a computer chip? Chips begin with quartz sand, which is made of silicon and oxygen. Factories heat it with carbon to separate out silicon, then purify it until it is nearly perfect. A crystal is grown, sliced into thin shiny discs called wafers, and printed with tiny circuits using light and special chemicals. Finally, each wafer is cut into many small chips. It takes hundreds of steps. https://socialmedia.xdme.com/tony/videos-book27/page-106.mp4 https://www.youtube.com/embed/Zrfqje479Fc 109 2026-10-09T14:55:25+00:00 yes https://xdme.com/watch-book27-q107.html https://xdme.com/book27-thumbs/page-107.jpg How do liquid crystals make pictures on a screen? Liquid crystals are strange materials that flow like a liquid but have molecules that line up like crystals. In a liquid crystal display, a thin layer sits between two filters. A small electric signal twists the molecules, which lets light pass through or blocks it. Millions of tiny dots called pixels switch on and off to make pictures. Calculators, watches, and TVs use this idea. https://socialmedia.xdme.com/tony/videos-book27/page-107.mp4 https://www.youtube.com/embed/5-NNOxEZZ2M 110 2026-10-09T14:55:26+00:00 yes https://xdme.com/watch-book27-q108.html https://xdme.com/book27-thumbs/page-108.jpg How do silicon crystals turn sunshine into electricity? A solar cell is a thin slice of silicon crystal with two layers treated slightly differently. One layer has extra electrons, and the other has gaps where electrons could go. Where the two layers meet, an electric push is built into the crystal. When light hits the cell, it knocks electrons loose, and the push sends them one way, which makes an electric current. Many cells together form a solar panel. https://socialmedia.xdme.com/tony/videos-book27/page-108.mp4 https://www.youtube.com/embed/2Ve7mC90Vyk 110 2026-10-09T14:55:27+00:00 yes https://xdme.com/watch-book27-q109.html https://xdme.com/book27-thumbs/page-109.jpg Why does the gap in an LED chip decide its color? An LED is a tiny crystal chip. When electricity flows, electrons drop across a tiny gap in the crystal’s energy, and they give off the extra energy as light. A bigger gap makes bluer light, and a smaller gap makes redder light. Makers choose crystals with the gap for the color they want. Blue LEDs were so hard to make that three scientists won a Nobel Prize in 2014. https://socialmedia.xdme.com/tony/videos-book27/page-109.mp4 https://www.youtube.com/embed/hfYtBlUNjJU 111 2026-10-09T14:55:28+00:00 yes https://xdme.com/watch-book27-q110.html https://xdme.com/book27-thumbs/page-110.jpg What was the first laser made from? The first working laser was built in 1960 by American scientist Theodore Maiman, using a rod of synthetic ruby crystal. A bright flash of light energized the atoms in the ruby. They sent out a red beam that was strong, pure, and straight. Today lasers use many materials, such as crystals, gases, and chips. They are used in surgery, scanners, and communications. https://socialmedia.xdme.com/tony/videos-book27/page-110.mp4 https://www.youtube.com/embed/RZlHaDpeMcM 110 2026-10-09T14:55:28+00:00 yes https://xdme.com/watch-book27-q111.html https://xdme.com/book27-thumbs/page-111.jpg Why are watch faces and camera lenses made of sapphire? Sapphire is a form of corundum, a crystal that ranks 9 on the Mohs scale, harder than almost anything except diamond. Lab-grown sapphire can be made into clear windows that resist scratches from keys, sand, and dust. It is used on fine watches, phone camera covers, and supermarket scanner windows. Because it's made in a factory, it doesn't have to be mined. https://socialmedia.xdme.com/tony/videos-book27/page-111.mp4 https://www.youtube.com/embed/3Na6kjaiR8k 111 2026-10-09T14:55:31+00:00 yes https://xdme.com/watch-book27-q112.html https://xdme.com/book27-thumbs/page-112.jpg Why are diamonds on saw blades and drill bits? Diamond is the hardest known natural material, so it can cut or grind almost anything. Tiny diamonds glued to the edge of a saw blade cut through stone, concrete, and tile. Drill bits tipped with diamonds can reach deep into rock. Sandpapers use other hard crystals, like garnet and corundum. The crystals wear away the softer material and stay sharp. https://socialmedia.xdme.com/tony/videos-book27/page-112.mp4 https://www.youtube.com/embed/EEbLHDj3iho 110 2026-10-09T14:55:32+00:00 yes https://xdme.com/watch-book27-q113.html https://xdme.com/book27-thumbs/page-113.jpg How did early crystal radios work? In the early 1900s, simple radios used a piece of mineral crystal such as galena and a thin wire called a cat's whisker touching it. The crystal turned radio waves from the air into tiny electric signals that could be heard in earphones. Crystal sets needed no battery at all, because the radio waves themselves gave the power. Many kids have built them. https://socialmedia.xdme.com/tony/videos-book27/page-113.mp4 https://www.youtube.com/embed/9d2x_vnzBto 111 2026-10-09T14:55:33+00:00 yes https://xdme.com/watch-book27-q114.html https://xdme.com/book27-thumbs/page-114.jpg Why are jet engine blades grown as one crystal? Inside a jet engine, hot gases are hotter than the melting point of the metal. The blades spin quickly and endure heat and force. Ordinary metal has many tiny crystals, and the boundaries between them are weak spots where blades slowly stretch. Engineers grow special blades from just one crystal of nickel alloy, so there are no weak boundaries. Tiny cooling holes also protect them. https://socialmedia.xdme.com/tony/videos-book27/page-114.mp4 https://www.youtube.com/embed/3QP4aT9rWQ8 111 2026-10-09T14:55:34+00:00 yes https://xdme.com/watch-book27-q115.html https://xdme.com/book27-thumbs/page-115.jpg What is graphene, and why is it special? Graphene is a single layer of carbon atoms arranged in a honeycomb pattern, just one atom thick. It is incredibly strong for its weight, bends, and conducts electricity well. In 2004, scientists in England first peeled graphene from graphite using sticky tape, winning the Nobel Prize in 2010. Researchers are exploring it for batteries, screens, and filters. https://socialmedia.xdme.com/tony/videos-book27/page-115.mp4 https://www.youtube.com/embed/8dCmQBcBuCE 113 2026-10-09T14:55:35+00:00 yes https://xdme.com/watch-book27-q116.html https://xdme.com/book27-thumbs/page-116.jpg Why do some crystals flash when invisible rays hit them? Certain crystals, such as sodium iodide, give off a tiny flash of light when X-rays or gamma rays hit them. Detectors use these crystals, called scintillators, to turn invisible rays into flashes that a sensor can count. They are used in medical scanners, airport machines, and space telescopes. Each flash tells scientists something about the energy of the ray. https://socialmedia.xdme.com/tony/videos-book27/page-116.mp4 https://www.youtube.com/embed/uvr17JyEX0c 114 2026-10-09T14:55:37+00:00 yes https://xdme.com/watch-book27-q117.html https://xdme.com/book27-thumbs/page-117.jpg Why do glow-in-the-dark stars glow? Glow-in-the-dark materials use special crystals, such as strontium aluminate. When light hits them, electrons jump to a higher energy and get stuck there for a while. Slowly they fall back and release the energy as a soft glow. The glow lasts minutes to hours, depending on the material. The more light the crystals absorb, the brighter they glow. https://socialmedia.xdme.com/tony/videos-book27/page-117.mp4 https://www.youtube.com/embed/rgOb_pBmgs8 108 2026-10-09T14:55:37+00:00 yes https://xdme.com/watch-book27-q118.html https://xdme.com/book27-thumbs/page-118.jpg How does plaster harden? Plaster of Paris is a dry powder made from gypsum. When mixed with water, tiny needle-shaped gypsum crystals grow through the mixture and lock together like a tangled mat, making it hard. The mixture warms up as the crystals form. People use plaster for casts, wall repairs, and crafts. Mixing and handling should be done with a grown-up, and plaster must never go down a drain. https://socialmedia.xdme.com/tony/videos-book27/page-118.mp4 https://www.youtube.com/embed/oIY8EPsRtks 112 2026-10-09T14:55:38+00:00 yes https://xdme.com/watch-book27-q119.html https://xdme.com/book27-thumbs/page-119.jpg Why does rain slowly eat away a limestone statue? Limestone and marble are made of calcite crystals. Rain is slightly acidic, because it picks up carbon dioxide from the air, and polluted rain is even more acidic. The acid slowly dissolves calcite, so sharp carved details turn soft and blurry over many years. Some stone also gets a crusty layer of new crystals, called gypsum. Caretakers clean old statues gently and sometimes cover them to protect them. https://socialmedia.xdme.com/tony/videos-book27/page-119.mp4 https://www.youtube.com/embed/Su9tYEUldUw 113 2026-10-09T14:58:40+00:00 yes https://xdme.com/watch-book27-q120.html https://xdme.com/book27-thumbs/page-120.jpg How do blacksmiths change a metal's crystals? Metal is made of tiny crystal grains. When a blacksmith heats metal and hammers it, the grains move, squish, and change size. Heating and then cooling quickly makes steel harder, and gentle heating afterward makes it tougher. Making metal with the right grains is the secret of strong swords, tools, and springs. Forges are very hot, so this is for watching only. https://socialmedia.xdme.com/tony/videos-book27/page-120.mp4 https://www.youtube.com/embed/sSkO6x3n8Tc 110 2026-10-09T15:01:41+00:00 yes https://xdme.com/watch-book27-q121.html https://xdme.com/book27-thumbs/page-121.jpg How does fluoride toothpaste help teeth? The hard outer coat of your teeth, enamel, is made of tiny crystals of a calcium mineral. Acids from sugary foods and germs can dissolve a bit of them. Fluoride, found in many toothpastes, can join the crystals and make them tougher against acid. That is why dentists recommend brushing with a small, pea-sized dab of fluoride toothpaste and not swallowing it. https://socialmedia.xdme.com/tony/videos-book27/page-121.mp4 https://www.youtube.com/embed/5oPGo7W_2KE 112 2026-10-09T15:01:42+00:00 yes https://xdme.com/watch-book27-q122.html https://xdme.com/book27-thumbs/page-122.jpg What are zeolites, and what do they do in cat litter? Zeolites are crystals full of microscopic holes and tunnels, like a sponge made of rock. Water and other small particles slip inside and get trapped. Some cat litters and water filters use zeolites to soak up moisture and smells. Chemists call them molecular sieves because they let small molecules in and keep bigger ones out. They are found in nature and can be made in labs. https://socialmedia.xdme.com/tony/videos-book27/page-122.mp4 https://www.youtube.com/embed/p10lelzNVxU 110 2026-10-09T15:01:43+00:00 yes https://xdme.com/watch-book27-q123.html https://xdme.com/book27-thumbs/page-123.jpg Why do some watches say they have jewels? In old-fashioned mechanical watches, tiny gears spin on pivots. To reduce friction and wear, makers set tiny bearings made of ruby in the places where the pivots turn. Rubies are extremely hard and smooth. Early watches used natural stones, but today the rubies are lab-grown. A watch that says 17 jewels means it has seventeen of these tiny bearings. https://socialmedia.xdme.com/tony/videos-book27/page-123.mp4 https://www.youtube.com/embed/IOpIrtwiQYk 110 2026-10-09T15:01:44+00:00 yes https://xdme.com/watch-book27-q124.html https://xdme.com/book27-thumbs/page-124.jpg What is a transistor, and why does a phone need billions? A transistor is a tiny switch with no moving parts. Made of silicon, it uses a small electric signal to turn a larger current on or off. The first one was built in 1947 at Bell Labs. Turning many switches on and off lets a computer follow instructions. A phone chip may have billions, each only a few nanometers wide. https://socialmedia.xdme.com/tony/videos-book27/page-124.mp4 https://www.youtube.com/embed/bev7cw-p7fg 111 2026-10-09T15:01:45+00:00 yes https://xdme.com/watch-book27-q125.html https://xdme.com/book27-thumbs/page-125.jpg Which gadget at home could not exist without crystals? Many can't. Your phone has silicon chips, a crystal-controlled clock, a liquid-crystal or LED screen, and maybe a sapphire camera cover. A watch ticks on quartz. A microwave beeps with a piezo disc. Solar panels, LED bulbs, and computers all depend on crystals. Take a look at the things around you: crystals are working behind the scenes everywhere. https://socialmedia.xdme.com/tony/videos-book27/page-125.mp4 https://www.youtube.com/embed/ZcE6iap5lqs 111 2026-10-09T15:01:46+00:00 yes https://xdme.com/watch-book27-q126.html https://xdme.com/book27-thumbs/page-126.jpg What are the safety rules for growing crystals at home? Grown-ups should handle all hot water, since hot liquids can burn. Use only safe ingredients such as table salt, sugar, and Epsom salt, and never taste your experiments. Wear safety glasses if a grown-up says to, keep jars away from little children and pets, and label everything. Wipe spills right away and wash your hands afterward. Good scientists always plan for safety first. https://socialmedia.xdme.com/tony/videos-book27/page-126.mp4 https://www.youtube.com/embed/4XtafFr2am0 111 2026-10-09T15:01:47+00:00 yes https://xdme.com/watch-book27-q127.html https://xdme.com/book27-thumbs/page-127.jpg How can you grow salt crystals in a dish? Ask a grown-up to stir table salt into warm water until no more will dissolve. Pour a thin layer into a shallow dish over dark paper and put it in a quiet, sunny spot. As the water evaporates over a few days, tiny cubes and stepped, hollow pyramids appear along the edges. Look every day with a magnifier and draw changes. https://socialmedia.xdme.com/tony/videos-book27/page-127.mp4 https://www.youtube.com/embed/QnJvgoQRMDw 104 2026-10-09T15:01:48+00:00 yes https://xdme.com/watch-book27-q128.html https://xdme.com/book27-thumbs/page-128.jpg How can you make rock candy? Rock candy is sugar crystals grown on a string or stick. A grown-up boils about three parts sugar to one part water until it clears, then lets it cool a little and pours it into a tall jar. A skewer rolled in sugar for seed crystals hangs in the middle. Over about a week, crystals gather on it. Keep the jar still and covered with a paper towel. https://socialmedia.xdme.com/tony/videos-book27/page-128.mp4 https://www.youtube.com/embed/SP-0i3VXqVk 103 2026-10-09T15:01:48+00:00 yes https://xdme.com/watch-book27-q129.html https://xdme.com/book27-thumbs/page-129.jpg How can you grow Epsom salt needles overnight? Epsom salt crystals grow fast. Stir equal parts of Epsom salt and warm tap water until it dissolves. Spread a thin layer on dark paper or a dish and put it in the fridge. After an hour or so, you will see long needle crystals shoot out like frost. The cool temperature makes the water unable to hold as much salt, so it crystallizes. Do not taste it. https://socialmedia.xdme.com/tony/videos-book27/page-129.mp4 https://www.youtube.com/embed/hsYMgm04bHQ 105 2026-10-09T15:01:50+00:00 yes https://xdme.com/watch-book27-q130.html https://xdme.com/book27-thumbs/page-130.jpg Can you grow crystals on a pipe cleaner shape? Yes. Twist a pipe cleaner into a simple shape, like a star or a heart, and hang it with a string from a pencil into a jar. A grown-up pours in a warm, strongly dissolved Epsom-salt or sugar solution. As the solution cools and evaporates, crystals attach to the fuzzy surface. After a night or two, your shape glitters. Real snowflakes are different, because they grow in clouds. https://socialmedia.xdme.com/tony/videos-book27/page-130.mp4 https://www.youtube.com/embed/RRn63ipRBT8 108 2026-10-09T15:01:51+00:00 yes https://xdme.com/watch-book27-q131.html https://xdme.com/book27-thumbs/page-131.jpg How can you make an eggshell geode? Wash half an eggshell in hot soapy water with a grown-up, rinse it, and let it dry. Then place it in an egg carton. A grown-up prepares a warm, strongly dissolved Epsom-salt or sugar solution and pours it into the shell. As the solution cools and slowly evaporates over a few days, crystals grow on the inside, a bit like a real geode. Wash your hands, keep it still, and do not eat it. https://socialmedia.xdme.com/tony/videos-book27/page-131.mp4 https://www.youtube.com/embed/-zw73eoiULI 105 2026-10-09T15:01:52+00:00 yes https://xdme.com/watch-book27-q132.html https://xdme.com/book27-thumbs/page-132.jpg Why didn't my crystals grow? Don't worry: crystals can be tricky. If no crystals show up, maybe too little salt was dissolved, or the water hasn't evaporated yet. If you only get a thin crust, it may have dried too fast. If the crystals are cloudy or tiny, the jar may have been bumped or cooled quickly. Try again with more dissolved material, more patience, and a still spot. https://socialmedia.xdme.com/tony/videos-book27/page-132.mp4 https://www.youtube.com/embed/d4Zpe61iYzY 107 2026-10-09T15:01:53+00:00 yes https://xdme.com/watch-book27-q133.html https://xdme.com/book27-thumbs/page-133.jpg How do salt, sugar, and Epsom crystals compare? Under a magnifier, they look different. Table salt forms tiny cubes. Sugar makes slanted, glassy blocks with pointed ends. Epsom salt grows long needles or thin prisms. These shapes come from the way each substance's particles fit together in its lattice. Comparing crystals from different materials is a classic way scientists identify unknown substances. https://socialmedia.xdme.com/tony/videos-book27/page-133.mp4 https://www.youtube.com/embed/0qNASIhKbsc 114 2026-10-09T15:01:54+00:00 yes https://xdme.com/watch-book27-q134.html https://xdme.com/book27-thumbs/page-134.jpg How can you test what helps crystals grow best? Plan a fair test. Pick one thing to change, like the temperature or the amount of evaporation, and keep everything else the same. Make identical jars with the same amount of solution. Put one in a warm place, one in the fridge, and one on the counter. Measure the biggest crystal in each after several days. Repeat to be sure. https://socialmedia.xdme.com/tony/videos-book27/page-134.mp4 https://www.youtube.com/embed/_XkY6lwKLrU 103 2026-10-09T15:01:55+00:00 yes https://xdme.com/watch-book27-q135.html https://xdme.com/book27-thumbs/page-135.jpg What can a microscope or magnifier show about crystals? A magnifier shows the flat faces and sharp edges of crystals, and a pocket microscope can show even more: tiny steps, bubbles, and cracks. Hold it close to your eye, then move the sample until it comes into focus. Good lighting from the side shows the shapes. A phone camera with a macro lens can also take close-up photos. Draw what you see. https://socialmedia.xdme.com/tony/videos-book27/page-135.mp4 https://www.youtube.com/embed/UyZ-yjihNAE 108 2026-10-09T15:01:56+00:00 yes https://xdme.com/watch-book27-q136.html https://xdme.com/book27-thumbs/page-136.jpg How would a detective identify a mystery powder safely? Detectives never taste or sniff unknown powders. With a grown-up, you can test known kitchen powders, such as salt, sugar, baking soda, flour, and cornstarch. Look at the grains under a magnifier. Feel how they pinch or squeak. See whether they dissolve in water. Baking soda fizzes with vinegar. Comparing results with a chart can help you tell them apart without tasting. https://socialmedia.xdme.com/tony/videos-book27/page-136.mp4 https://www.youtube.com/embed/BpoOxJFWrRU 110 2026-10-09T15:01:58+00:00 yes https://xdme.com/watch-book27-q137.html https://xdme.com/book27-thumbs/page-137.jpg How do mineral detectives use an identification key? An identification key is a flowchart of questions. Is the mineral shiny like a metal or dull? Is it harder than a copper coin? What color streak does it leave? Does it split in flat sheets or break in curved shapes? Each answer leads to the next question until you reach a name. Using a key trains you to notice careful details instead of guessing. https://socialmedia.xdme.com/tony/videos-book27/page-137.mp4 https://www.youtube.com/embed/6-SX7vdAUOI 97 2026-10-09T15:02:29+00:00 yes https://xdme.com/watch-book27-q138.html https://xdme.com/book27-thumbs/page-138.jpg How can tiny crystals tell us how old Earth is? Zircon crystals, found in western Australia, are about 4.4 billion years old, among the oldest bits of Earth's crust ever found. When zircon forms, it traps tiny amounts of uranium. Over time, the uranium changes into lead at a steady rate, like a very slow clock. By measuring how much has changed, scientists calculate the crystal's age. https://socialmedia.xdme.com/tony/videos-book27/page-138.mp4 https://www.youtube.com/embed/X0w6up22w-c 114 2026-10-09T15:05:31+00:00 yes https://xdme.com/watch-book27-q139.html https://xdme.com/book27-thumbs/page-139.jpg How did a scientist use crystals to see the shape of medicines? Dorothy Hodgkin was a British scientist who used X-rays to study crystals of important molecules. Between the 1940s and 1960s, she worked out the structures of penicillin, vitamin B12, and insulin by studying their crystals. Knowing the shapes helped doctors and chemists understand how they work. She won the Nobel Prize in Chemistry in 1964. https://socialmedia.xdme.com/tony/videos-book27/page-139.mp4 https://www.youtube.com/embed/X1gNSTk-tQo 115 2026-10-09T15:05:31+00:00 yes https://xdme.com/watch-book27-q140.html https://xdme.com/book27-thumbs/page-140.jpg What can crystals tell us about other planets? Mars rovers have found crystals that are clues to the planet's past. Curiosity found veins of gypsum, a mineral that forms in water. Opportunity found little round pieces of hematite nicknamed blueberries, which also grew in watery places. Seeing these crystals tells scientists that liquid water once soaked the Martian ground. Crystals are like fingerprints for the places they grew. https://socialmedia.xdme.com/tony/videos-book27/page-140.mp4 https://www.youtube.com/embed/fqVo8BVfgtE 114 2026-10-09T15:06:03+00:00 yes https://xdme.com/watch-book27-q141.html https://xdme.com/book27-thumbs/page-141.jpg Who are the scientists that study crystals? Many careers revolve around crystals. Mineralogists study natural crystals and minerals. Crystallographers use X-rays to find the atoms inside. Gemologists identify and grade gems. Materials scientists create new crystals for electronics and energy. Geologists in the field, like those at the Geological Survey of Canada, hunt for minerals. Museum curators care for collections. You can start as a curious rock hound. https://socialmedia.xdme.com/tony/videos-book27/page-141.mp4 https://www.youtube.com/embed/mDCMGv9n70Y 118 2026-10-09T15:10:36+00:00 yes https://xdme.com/watch-book27-q142.html https://xdme.com/book27-thumbs/page-142.jpg How can you make art with crystals? Try salt painting. Draw with white glue on thick paper, sprinkle salt on the glue, shake off the extra, and then dab watercolor onto the salt. The color spreads along the grains, making sparkly patterns. You can also photograph crystals under a magnifier, or draw their shapes. Artists have long used crystals and minerals for pigments, jewelry, and sparkling glass. https://socialmedia.xdme.com/tony/videos-book27/page-142.mp4 https://www.youtube.com/embed/8gzYeOf9I5w 109 2026-10-09T15:15:38+00:00 yes https://xdme.com/watch-book27-q143.html https://xdme.com/book27-thumbs/page-143.jpg Are any crystals or minerals unsafe? Most rocks are safe to handle, but some need care. Never taste minerals. A few contain harmful metals, so wash your hands after handling. Dust from cutting or grinding rocks can hurt your lungs, so professionals wear masks and use water. Sharp edges can cut. Always ask a grown-up before collecting rocks or handling unfamiliar ones, and leave sites with unsafe cliffs or loose rock alone. https://socialmedia.xdme.com/tony/videos-book27/page-143.mp4 https://www.youtube.com/embed/uhLWOoSUD9M 109 2026-10-09T15:20:11+00:00 yes https://xdme.com/watch-book27-q144.html https://xdme.com/book27-thumbs/page-144.jpg How do you take care of a crystal collection? Some minerals need gentle handling. Halite and Epsom salt dissolve in water, so keep them dry. Amethyst and rose quartz can fade in strong sunlight. Soft minerals like gypsum scratch easily, so store them apart from harder ones. Use boxes with soft padding and labels, and dust with a soft brush. Handle specimens by their sides and keep them out of reach of small children. https://socialmedia.xdme.com/tony/videos-book27/page-144.mp4 https://www.youtube.com/embed/eco7MxKFcfM 109 2026-10-09T15:24:44+00:00 yes https://xdme.com/watch-book27-q145.html https://xdme.com/book27-thumbs/page-145.jpg What is a quasicrystal? In 1982, scientist Dan Shechtman saw an atom pattern that looked orderly but did not repeat, which scientists had thought was impossible. Many doubted him, but other experts later confirmed it, and he won the Nobel Prize in Chemistry in 2011. These materials are called quasicrystals. Scientists have even found natural ones in a meteorite. They show how nature can surprise us. https://socialmedia.xdme.com/tony/videos-book27/page-145.mp4 https://www.youtube.com/embed/Np3i2vZsmAs 116 2026-10-09T15:29:46+00:00 yes https://xdme.com/watch-book27-q146.html https://xdme.com/book27-thumbs/page-146.jpg What are scientists still trying to figure out about crystals? Many puzzles remain. Scientists want to predict how atoms will arrange from just a chemical formula, and why one material can crystallize in several forms. They still study exactly how a crystal first starts to grow. And they search for new crystals with special powers for energy, medicine, and electronics. Every answer leads to new questions. https://socialmedia.xdme.com/tony/videos-book27/page-146.mp4 https://www.youtube.com/embed/M6JZf9U-1xE 111 2026-10-09T15:34:49+00:00 yes https://xdme.com/watch-book27-q147.html https://xdme.com/book27-thumbs/page-147.jpg How do you make a crystal field guide? A field guide is a small book that helps people identify things. For each crystal or mineral, make a page with a photo or drawing and facts: color, shine, hardness, streak, shape, and where it is found. Add a space to record the date and place of your sample. Keep it neat and clear so a friend could use it. Share it with your class or family. https://socialmedia.xdme.com/tony/videos-book27/page-147.mp4 https://www.youtube.com/embed/JantV3B9Jkw 103 2026-10-09T15:39:21+00:00 yes https://xdme.com/watch-book27-q148.html https://xdme.com/book27-thumbs/page-148.jpg How do you keep a crystal journal like a scientist? Write down the date, ingredients, amounts, temperature, and how long you waited. Add drawings or photos each day. Record surprises and failures, too, since they help you learn. Compare your notes from different experiments. A journal lets you repeat what worked and share your results with other people. Scientists trust results that can be checked. https://socialmedia.xdme.com/tony/videos-book27/page-148.mp4 https://www.youtube.com/embed/reWEH0yOj1g 111 2026-10-09T15:46:54+00:00 yes https://xdme.com/watch-book27-q149.html https://xdme.com/book27-thumbs/page-149.jpg Could crystals help solve future energy problems? Scientists are looking at crystals for cleaner energy. New solar cells use crystals called perovskites that might be cheaper to make. Better battery materials are crystals that store and release energy more safely. Other researchers explore crystals that turn waste heat into electricity. These ideas are still being tested, but crystals may help power the future. https://socialmedia.xdme.com/tony/videos-book27/page-149.mp4 https://www.youtube.com/embed/1zp5TOImU9k 116 2026-10-09T15:48:56+00:00 yes https://xdme.com/watch-book27-q150.html https://xdme.com/book27-thumbs/page-150.jpg What will you grow and discover next? You now know that crystals are everywhere: in your kitchen, your clock, your teeth, and the rocks outside. Keep looking with a magnifier, keep asking questions, and keep experimenting safely. Whether you become a rock hound, a chemist, or an engineer, the same curiosity that makes you wonder about crystals will lead you somewhere amazing. What will you find? https://socialmedia.xdme.com/tony/videos-book27/page-150.mp4 https://www.youtube.com/embed/EvHVu0ZW6L8 113 2026-10-09T15:53:28+00:00 yes