Ugh, they have a damn network monitoring program installed... my school uses NetOp, any teacher can see ur screen in plain view and control your desktop and it wouldn't be any suprise that your school has a similar program installed with similar features....

Morale of the story, don't do stupid **** like download stuff on school computers.. you're just eating the school's bandwidth and giving them a better than average shot of getting infected with some skiddie virii.