Fun but Easy
I had almost all the upgrades by the end of the third level. It was a cute game, but definitely very easy. I wasn't sure if this was the intent or not, though, since with the graphics and so forth it could've easily been targeted to the 10-and-under crowd (and very well done, too). It'd be nicer to see difficulty levels which jacked up the amount of experience you needed for each level or something, tho.