Our house has 3 bathrooms. The "kid" bathroom is the main one in the middle of the house. There's a 3/4th bath off the guest bedroom. The master bath has a door to the sun room.
Most of the kids' toys are in the sunroom so that's where they spend most of their time. They almost always use the master bath. The tub in there is biggest so that's where they take baths too.
But as they get older I kind of want some privacy.
So you have a bathroom your kids mainly use?
Pens, pencils, markers, etc.