what's gotten into her?

After swimming lessons last Friday, Maddy wanted to play in the small area designated for little kids who are waiting for their siblings to finish up lessons.  As with all kids' play areas, it usually looks as though a hurricane tore through it.  I sat down, checked some emails and when I looked up, you can imagine my complete surprise when I saw Maddy.....organizing and cleaning up!  Huh?

Why do you suppose she got the urge to CLEAN up this space?  Why doesn't she ever have those urges at home?