It is not a good idea for coed sleep overs with teens. Never! I know some parents do permit these but IMHO it is putting your child in a situation they are too young for. As a parent it is our job to guide them to good decisions (this party isn't a good decision- again imho). Some schools have Lock-ins with prom, where the kids will go to a place like a bowling alley or an arcade, where they can be involved with activities (safe) and these are chaparoned, and they aren't sleeping, and then everyone goes home at the early morning hour. I hadn't heard of them for other dances, but my youngest is 24. If you don't want your daughter "sleeping" with her boyfriend, why would you let her be in an environment that would make it too easy to do? I didn't read all the posts but I doubt that there would be a few parents at the house staying up all night chaparoning. My position on my kids(-boys or girls- I have both) ws that they never would be allowed to attend coed sleepovers. If they wanted to get together for breakfast they could return for breakfast. I only remember one time it came up, and I said no, and I think my daughter had mixed feelings-she didn't want to miss out on fun, but was I think a bit uncomfortable with the idea. And I think she had even shared after the fact that she was glad she didn't get to go. Sometimes love means saying No.