In high school, we spread a bag of flour on the top of the blades of the ceiling fans in the Home Economics (cooking) room when the teacher was out. The next warm day, when she turned them on the entire fucking room got coated like a snowy day. I used to steal the chocolate out of the cooking cupboards there. Our teacher ended up chaining the door shut, but the chain links weren't welded, so I bent them open, got the chocolate out, then bent them closed again. I only ate a few, then left the bad on her desk. She never figured out how we got them out.