Activity: A cup of science

My son came home from the school science fair and replicated this quick little experiment he saw there.

Fill a pot with water.

Take a drinking glass and stuff a paper napkin in the bottom so that it stays put.

Turn the glass upside down and quickly immerse it in the pot of water. Then pull it out - the napkin is dry! A miracle, you say? Not at all - the cup isn't really empty, it's filled with air. The air keeps the water out of the cup and the napkin stays dry. This is one of many science experiments that help demonstrate that air isn't empty space.