A series of twenty non-fiction science readers which engages children in the world around them. Why is the sea salty? Why do boats float? Why do I feel thirsty? You can find the answers to these and other questions about water and weather in Why Do Raindrops Fall? Why is the sea salty? Why do boats float? Why do I feel thirsty? You can find the answers to these and other questions about water and weather in Why Do Raindrops Fall?