When I was young we live with my grandmother for a while. She decided one day to pick up all the stuff we left lying out. That included hair brushes, socks, toys, etc but did not include school supplies or books. We never saw any of it again. Did we learn our lessons? Nope. One day a few years later my sister and I got real nosy about what was hidden in her spare dresser where we found everything she had collected. I didn't take this tact with my sons -- I simply moved their stuff to their rooms and closed the door.