I don't know what happened and what damage was done, but this seems like punishment that has gone too far. Make the kids and their families pay for any damages that may have occurred due to this, and make them perform community service at the school. This, IMO, is just a lack of leadership from a principle who apparenlty can't teach a lesson, and who is relying on a judicial system to send the message for him. This is not the place for high school discipline where no one got hurt.