A friend of mine with a problem similar to yours solved it by covering the
window with paper. In the center he cut a hole at eye level, just large
enough for a face. Inside, he painted a monster with horns so that the room
occupants got a laugh at anyone who chose to peek in.
I love this Idea! I think I'll use it on my classroom door. That way when
the "headmaster" tries to sneek a peek I'll get to laugh! Thanks!