paperclipping
Should your teacher exhibit such a lack of fashion nous as to dress in trousers with turn-ups, you must spend a significant amount of time "accidentally" dropping your pen, allowing you to get on the floor and flick paperclips at his legs with the aim of landing them in the turn-ups.

Chris Spedding was so adept at this game that Mr Law often walked out of RE lessons to a jangling musical accompaniment.
written by excluded pupil, approved by Phil