Education.com: Where's the Air?

[Free Registration/Login Required] How can you tell that air is real if you can't see it or feel it? One way we can tell that air exists is by observing some of the things it does. Air can fill a balloon, for example, and when it's in the form of wind, it can move leaves and blow your hair around. Here's a quick, fun experiment that your child can do with just a few things from around the house.