I like what our school system does. We have an After PRom function at the school that lasts from 12Midnight till 0500. Once you're inside you can't leave and come back, if you leave, you;re done for the night. Its $5 (the prom cruise this year is $95/person). My son will go to that. And the thought of underaged drinking chills me, especially since I have to patch up the young fools when they come in unconcious to the emergency room!
We had one of those my senior year of high school. It sucked. Most boring thing ever, and everyone wanted to leave by 2. I would definitely recommend anyone who's school is having one of those things that they shouldn't go. Don't waste your time.