I'd have to say Club Penguin, Fantage , Moshi Monsters, Poptropica, Super Secret, and Our.com
Free Virtual World For 8 To 10 Year Olds Where You Can Shop And Chat And Win Money By Playing Games?
Clubpenguin
Stardoll is brilliant !
I think that woozworld is good for kids 10 and up
8 to 10 year olds? Children are supposed to be 13 to be online by themselves.