Ack, well I'm glad you didn't get suspended, SG!
I don't think police were needed (maybe they did that to cover themselves if your parents sued them or something!) and I wouldn't exactly call rubber bands and paper a 'weapon'!
But I do know that one reason they get irritated about such things on school buses is because of the safety issue. If one of those were to hit the driver and he/she went off the road or into a guard rail, you'd all be in some trouble.
Anyway, you'll graduate to water guns by senior year...