That's a wonderful idea! I'm going to be on the look out for hula hoops now. I remember having to put a line of masking tape through the room my two youngest daughters shared when they were little because one was a neat freak and the other, well, not so much. I could define the space in my toyroom in different ways like that with a line of toys for instance especially so the ones who love to build towers don't have them crashed by the 1 year old children. That's our biggest issue.