You could also do the classic laxative in cookies, brownies and such as well. Or if you don't mind stealing and if your school doesn't have cameras. Find a farmer with a bunch of chickens, take them, and on your way out of school, unlock a window, dump the chickens in the halls and book it. That helps if you dump a bag of chicken feed on the floor too. That was the original attempt for a high school prank before everyone pussed out and just wrote 03 on cars. That 03 b.s. wouldn't have even bothered me so much, but I was supposed to have seen some boobs in the process (I was in on a deal, I draw a pornographic picture, someone shows me their boobs) and I got ripped. Now I've moved about 20 minutes away and I'll never see any of those dweebs again, thus no chance to get my pay. Bastards.