Ok first of all I do not suggest doing magic at school in the first place, so technicly I dont even condone what I am saying. If you really want to do magic at school, leave the cards at home and just use a friggin FORK! liquid metal or Steve Shaws's ( Banachek ) dvds are perfect for this.... I mean what can go wrong with forks, fully examinable and an amazing trick plus you can throw the fork away after your 30 seconds of fame and just leave people mistified!
The only problem I see with this is the use of forks so !!!DONT!!! do magic to every day to be popular, be your bloody self and see if people like you for your personality not your magical ability! Just show the tricks once in a while maybe once a moth to a small group of 5-10 people.
Anyway thats just my $0.02 on school magic
if you have any complaints about my rant please send post email them to IDONTREALLYCARE@ABOUTSCHOOLMAGIC.COM