Tap, plink, tweet, and tootle. Here are four simple instruments you and your friends can make. Each instrument belongs to a big family---it has lots of \"relatives" that make music in the same way. ...
A push in a wire
should go. Click! The minute you turn on a lamp or a radio, something happens---a light bulb glows or sounds come out. But electricity doesn't jump into the lamp or the radio. It flows through...
Books, tires, and string
The next time you read a book, ride a bicycle, or fly a kite, thank the plants. Without them, you might not be able to do any of those things. The paper in most books comes from trees. To make...