It sounds like you might be OCD. The inability to sit down and relax without everything being in it's place is a good sign that you're not able to function within this....issue.
I suggest you google OCD and see if it fits, only you know the answer to that.
IF it does then you need stuff out of sight all the time. When the kids come in they need a cubby to sit their shoes in and a place to hang a jacket. Then they might have a hook for their backpack. Otherwise nothing goes in this room.
Then you're going to have to learn to shut their doors and let them have their space. They need a space to be at home, not on constant clean up duty. Let them live in their rooms.
I also suggest you get rid of everything that is sitting out on table tops, shelves, mantles, etc....so that you'll feel like it's less cluttered. One of my friends didn't even have pictures or anything decorative in their public living space. She couldn't handle the clutter.
Another friend had her special magazines lined up exactly the same space apart with the remote exactly parallel to one of those edges. Her family lived in hell because she was constantly getting up and straightening their space while they were just trying to live at home and relax. It was not a happy environment.
So get rid of stuff. Toys out, books out, magazines out, every single item that is not needed needs to go away.