It would sorta help to know the lay-out of your property and what you have to work with. From your discription, I'm thinking you live in one of those communities where the rules for "outdoor stuff" is really strict.
Here's an idea.... what about building a special patio (possibly raised over 6 feet in the air?), and use the underside for storage.
Or maybe just some lattic around it in a nice way? Sorta blocking it, and making it noticable where no kids will run right into it?
Anywho.... welcome to the forum.
We'll help you come up with some ideas if we can.