<p>When my children were teens I just kept the doors to their rooms closed. I cleaned their bathrooms. They were not allowed to leave their backpacks, sports equipment, papers, etc in public spaces of the house. They were allowed to have one book in a public space :)</p>
<p>The fall everyone had gone to college I decluttered and cleaned from attic to cellar. Even the kids’ rooms. I packed up all the memorabilia that wouldn’t fit on the walls and shelves.I organized their closets. I packed up everything extra and labeled it with their names in the attic. One kid was truly amazed. He thought it was unbelievably wonderful. I told him, kind of joking, that if every time he removed an item from a particular place he put it back in that particular place, everything would always look just like that. Suddenly he was the neatest person I know. Years later he has an extremely neat apartment and always picks up after himself AND his sibs when they are home for a holiday.</p>