A camel's hump is not full of water. It stores fat, and the camel's body uses that fat for energy when food is hard to find in the desert. What is inside a camel's hump?

When a honeybee finds flowers, it flies back to the hive and moves in a waggle dance. The dance tells the other bees which direction to fly to reach the food. What does the waggle dance tell the other bees?

An octopus has three hearts. Two of them push blood to the gills, and the third heart pumps blood to the rest of the body. What do the two gill hearts do?

Many bats hunt at night. A bat makes high squeaks and then listens for the echoes that bounce back off insects. The echoes tell the bat where the insect is. How does a bat find insects in the dark?

On December 17, 1903, Orville Wright flew the first powered airplane at Kitty Hawk, North Carolina. That first flight lasted only 12 seconds. Where did the Wright brothers make the first powered flight?

Louis Braille had been blind since he was three. In 1824, when he was 15, he built a code of raised dots that a blind reader can feel with a fingertip. What did Braille use to make his code?

The Statue of Liberty was a gift to the United States from the people of France. It was unveiled in New York Harbor in 1886. Who gave the Statue of Liberty to the United States?

Beavers cut down small trees with their strong front teeth. They pile the sticks and pack them with mud to build a dam across a stream. What do beavers use to build a dam?

Each fall, monarch butterflies leave Canada and the northern United States and fly about 3,000 miles south. They spend the whole winter in fir forests in central Mexico. Where do the monarchs spend the winter?

An owl can fly almost silently. Comb-like edges on its wing feathers break up the rushing air, so a mouse never hears the owl coming. What makes an owl's flight so quiet?

The center of a hurricane is called the eye. Inside the eye the wind is calm and the sky is sometimes clear, while the strongest winds spin in the ring of clouds around it. What is the weather like inside the eye?

Lightning heats the air around it in a flash. That hot air spreads out so fast that it makes the loud boom we call thunder. What causes the sound of thunder?

Melted rock deep under the ground is called magma. Once that melted rock reaches the surface and pours out of a volcano, people call it lava. What is melted rock called after it reaches the surface?

Coast redwoods are the tallest trees on Earth, and some grow more than 350 feet tall. They grow in the foggy forests along the coast of northern California. Where do coast redwoods grow?

The Sahara is the largest hot desert in the world. It stretches across northern Africa and is nearly as big as the whole United States. On which continent is the Sahara?

Tiny green algae grow in the damp grooves of a sloth's fur. The green tint helps the slow sloth blend in with the leaves, so hunters below do not spot it. How do the algae help a sloth?

In 1941, a Swiss man named George de Mestral came home from a walk and found prickly burrs stuck to his pants. He looked closely, saw thousands of tiny hooks, and got the idea for Velcro. What gave de Mestral his idea?

In 1860, Pony Express riders began carrying mail from Missouri to California on horseback. A rider swapped to a fresh horse about every 10 miles. In what year did the Pony Express begin carrying mail?

An African elephant has huge ears that are full of blood vessels. When the elephant flaps its ears, moving air cools the blood inside them, and the cooler blood cools the whole animal. Why does an elephant flap its ears?

Weather scientists use a tool called an anemometer. It has small cups that spin in the wind, and the faster the cups spin, the stronger the wind is. What does an anemometer measure?