Like Sorcha I never did anything bad except the gum thing recounted on another thread. My younger brother was always up to mischief however. He had a teacher with a hearing aid and actually went up to him mouthing a question - no sound. The poor man kept turning up his hearing aid and fiddling with the batteries. He finally gave up and said "Speak louder!" John did and nearly killed him.
Just remembered antoher - I guess I did do one or two things. I attended an all girl high school. Saran wrapping the toilet and then putting the seat down ensured an embarrassing mess whether you sat or not. Vaseline on the seat only worked for sitters.