I skipped a lot because of bullies, boredom and barbiturates (quaaludes). Also, I put an "I bought my bong at Black Doggs" (a popular local head shop)bumpersticker on a teacher's car. Told the study hall teacher I was going to the library but wandered around downtown instead, hung out with some potheads in front of the Alabama Theatre, went to English class stoned out of my gourd, took my French final and got a 97
while high as a kite, made wild-goose chases in textbooks that said, "turn to page 98", then on page 98 I'd write to turn to another page, etc.. There was never any paypff. Smoked in the bathroom.
In college, we had to use dry ice in a play and there was some left over so we put it in the toilets in the ladies room of the humanities building.
That's about the worst thing I did at school in college. Most of my college mischief was after hours. 
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"Lonely is as lonely does.
Lonely is an eyesore."