Is coming from sciencegeekgirl’s Hands on Science Sunday: Feeling pressured?

All you need is a big trash bag and an industrial strength vacuum cleaner, and a willing victim (er, “faithful subject of science.”) The victim (aka “subject) gets inside the bag, and once you suck all the air out of the bag with the vacuum cleaner, they’ll feel an intense pressure. SAFETY FIRST! Read this PDF writeup of the activity (from the Exploratorium’s Eric Muller) for all the ins-and-outs and safety factors in doing this with your kids. (Words to the wise — don’t put your head inside the bag!) It’s stunning — try it if you can.