How are mountains formed? What makes the air we breathe? What causes the ocean waves? Now you can learn the answers to these and other questions aboutthe earth,

How do plants make their own food? Why do the different strings on a guitar have differentsounds? What does the color of a star tell you about how hot the stari

What makes the heart beat faster or slower? How do tightrope walkers keep their balance? Why does spinning fast cause dizziness? Explore the mysteries and the w

Why is the ocean salty? How do whales stay warm? What causes tides to rise and fall? How do oil spills affect ocean animals? Now you can discover the answers to