Mr. Vanden Heuvel is in the bathroom again! This time he examines the strength of atmospheric pressure with a classic demonstration of filling a glass with water in the sink to reveal the column that fills the glass. Then he places a plate at the opening and lifts the cupful of water out of the sink. The air pressure beneath the plate holds it tight against the glass. How about having your class perform this trick at home or in the lab rather than just showing the clip?