nice ideas here - wish I were in school again.. but that train has departed quite some time ago.. 
I liked to do some mischief, but mostly tried to do so without getting punished or having my mother informed.. (like most mothers, she has the worst case of 'I'm so disappointed in you'-stare)
first of all, get allies.. I used to pick a few good natured teachers nobody respected (you know them. they're nice and enthusiastic and desperately want to teach you something.. anything) and do everything I could in their class - show interest (by asking questions, but not in a disruptive way (see below), do homework and extras and so on.. teachers talk - unrespected teachers (because they're too nice) will remember you and stand up for you.. saved my hide a lot of times when conferences had me as a topic
know your teachers. some have low self esteem, others are nervous, and so on. play on those weaknesses, don't try to pull stuff on someone who won't react to it - thats just wasted effort. make them lose their patience so they get angry and react badly - they often won't report you when they themself are on the line. if they do, make sure to report every single one of their failures.. or if you get a teacher to be angry, shouting and being near to beat you.. start crying and say 'please, don't hit me, please' with as much fear as you're able to simulate. reacting as they don't expect makes them confused
mostly you don't want to get caught, but for some stunts you need to for them to work.. then its good to be obvious - the teacher will have his moment of 'I caught you'-pride until he realizes he wished he hadn't 
some random thoughts with more or less value (mostly less, I fear.. damn beer *g*):
1. ask ask ask.. always start the next follow-up question with 'but'.. but isn't it .. but didn't you say.. but i always thought..
2. use a paper clip (or whatever its called in english, this bent wire to hold papers together), to pick the teachers desk-lock (only works if its a cheap one). if theres an unannounced test - learn. and if the wire accidentally breaks.. oops but never do that in front of to many students - theres always a narc
3. if you get thrown out of class and theres a tree outside the classroom. climb it, shake the tree as much as you can. I didn't get thrown out of this class anymore - my presence was less annoying than my absence. (I'm not sure what happens in other countries - I just got thrown out to roam the school grounds for the rest of the class. .but that may be just switzerland *g*)
4. for girls only: get guys to do the dirty work. even not being interested in girls I often found myself doing stuff which got ME into trouble.. and never the initiators, those devilish girls
5. be late and use stupid reasons (I didn't find the way in the fog/I forgot which classroom I had to go to) - only recommended if your teacher has not lost his sense of humour yet..
6. do as if you were supressing hysterical laughter.. barely.. when teacher asks, say its nothing, you're sorry.. repeat. teachers with low self esteem will take it personally and try to figure out what they did wrong..make them doubt themselves..
7. tap your fingers on the desk.. when you're asked to stop - continue, whithout making a sound (tapping your fingers on the back of your other hand)..
8. know more than the teacher.. thats usually not possible in the main courses.. but in lessons like IT its simple.. rub in their every mistake
9. use a screwdriver to loosen the knobs on every closet.. DON'T ask the teacher to get something.. thats too obvious. it will happen somewhen anyway.
10. if you have those pneumatic stools. sit on them and let them down. then stack. than pull the lever on a few to raise them again. you'll have a stool-tower snugly fit between floor and ceiling - only way to get them apart is to kick in the middle and run away from the falling stools.
11. if theres one of those paper-cut machines (where you position the paper and then pull the knife down): just befor the edge where its cut, theres often a metal part to hold down the paper. put some oil colors in between the gap.
12. hide a few fresh eggs in the classroom (hide them good!).. for a faster reaction.. use a fish
13. give your teacher a gift-wrapped deodorant or use a spray-deo when he/she walks by or obviously hold your breath whenever the teacher is talking near you.. just nod an as soon as he leaves, take a large breath of air with as much sound as possible.
14. if you're teacher is a smoker.. get a cigarette and play with it in front of him.. as a smoker myself I can say that this would make me want my next cigarette even more
15. write your teachers name and paint a few hearts around it - be obviously secretive. most teachers will want to see the paper
sorry for the strange explanations, my english vocabulary seems not to cover all that stuff
ora
