I came up with this idea for my grandkids’ playhouse. There is a two-sided sign which they can display on the door which states either “No Girls” or “No Boys.” We had a party where each parent and child painted their wall section in order to teach the colors to the kids. My wife will stencil alphabets, numbers, animals, vehicles, etc. on each wall, then the oldest grandchild will hold classes for the younger ones.