My daughter, who is now 23, has a LOT of friends. Often a troop of a dozen would come for dinner Friday nites. We still get bunches staying over. Also, I did a lot of work for the NYC school system, and her HS, in particular. Even though, in theory, for most of that time, phones weren't allowed, they would allow them as long as they weren't out, and used.Go into a middle school or a HS with a few thousand teens, and you'll see a lot of phones in back pockets.