I start by putting some water in the bottom of an empty coke can. I put just enough water to fill the bottom... About a table spoon or so. I put it on the heater so that I can replace the air inside the can with water vapor...
Once I boil the water for a minute or so and allow the can to fill up with water vapor... I turn the can upside down and drop it in some cold water. The water vapor condenses back to liquid water and because liquid water takes up less space, a void is created.
Therefore, the can has no choice but to "implode" on itself! Sure it is simple, but I love the sound an imploding can makes! If I ever come and visit a your kids' school, there is a high chance that I will do this little trick!
I had a great time visiting with the teachers and kids at Success School and I believe I will be going back there in a few days to talk with the younger kids.
Do any of you have some cool science experiments in mind? If so, drop me an email!
PS- I always test my experiments with my kids first. If they like it, then I take the ideas to school with me!