Keeping track of kids.

Have you considered putting dutch doors on the rooms the kids are in? This allows you to keep the bottom half closed and the top half open. We had these at a daycare where I worked and they were great. The kids couldn't get out and we could see in thus being able to monitor their bedtimes better. Another benefit is the doors have a latch and can be truned back into a solid door when the kisd are older.