Parents need to know that Umigo is a kooky, beautifully designed math and engineering game site that's geared toward younger kids. Kids create a personalized avatar but they don't use real names, and interaction is limited to showing off songs or vehicles they've created. Although there are lots of outstanding opportunities for learning, some kids may get hooked on saving UMI bucks to purchase parts for their vehicles, new instruments, or virtual decorations for their room. But they'll have to succeed at math games to feed their addictions. Also, Umigo's animations are wildly entertaining and will keep your kids laughing as they learn.