@cmsmith10: I have hosted two after-prom parties. For the most part, they went smoothly. I tried to give them their privacy but I did make rounds about once or twice to make sure things were not getting out of hand.
We have a basement so the party was down there. We hired a DJ and the kids loved it. Make sure there are plenty of party treats available. Sometimes, we will order several pizzas.
Another important thing is to make sure that there is someone outside to mandate parking areas. It can get out of hand, otherwise.