How to motivate a little girl to clean her playroom? help me!!

So it has been a little while since I posted something, I can't sleep so I am up and playing on the computer. I was sitting here thinking about how thankful I am for my family. My daughter Alexis is really growing too fast. She also is becoming mommy's good little helper, and I love it. Lets see if that attitude will last through her teenage years. ha! Just a few things Lexi loves to do to help me out: wipe off the table, take dishes to the sink, remove sheets from the beds, dust, cook and she will do all this with a big smile on her adorable little face. And her smile will soon be followed by a "am I good helper mom?" However, when it comes to cleaning her playroom up, not exactly the same attitude. So I guess I won't have to wait for the teen years, but I just need new ideas to motivate my daughter to pick up her toys! any ideas?