Heavy Air

2 sheets of newspaper
1 ruler
1 friend
1) Place the ruler on the table with about 3 inches hanging over the end.
2) Place the two sheets of newsprint over the ruler, keeping it in the middle, and smooth them so that there is no air between them and the table top.
3) Hit the end of the ruler hard. If you hit it hard enough, the ruler will break. Explanation: By smoothing the paper, you pushed most of the air out from under it, but there is still a lot of pressure from the air above it. When you hit the stick, it breaks because it can not rise up in response to the force you used on it, the air pressure above is too high.