I made this for my high school chemistry project. We made it in the morning so it would be ready for our afternoon class.

It was drying in the chemistry back office and there must have been a draft. It exploded during a silent study hall.

Somehow they let us remake it for class that afternoon. We tried to put it on the floor as a joke, but our teacher was wearing sandals that day (no lab). She wasn't happy about it.

I originally got the idea (and prank idea) the previous year from a retiring chemistry teacher.