
I always liked Funbrain, and they have good games and sites for vocabulary. You can also create your own reviews.
http://www.funbrain.com/words.html
Funbrain Word Games
This is a primary site. It shows a picture and you choose the correct word.
http://www.funbrain.com/vocab/index.html
Games Whats the Word
Kids Word of the Day there's a good word of the day for kids,
http://superkids.com/aweb/tools/words/
Are you a "word nerd"? Check out the 50 coolest sites for word nerds at this link. Save the Words (a site that allows you to to "adopt" words that are in danger of disappearing from the lexicon) and Morpheme Machine
(for creating new words from morphemes) are two of my favorites:
Word nerd
http://bit.ly/bIeP4q
Word Play
Is there a site that will analyze the letters of a word and create new words from the original word?
Example: "snowstorm"
snow storm now won, etc.
Betty
They have words inside of words, word jumble, Boogler, etc.
Great site!
http://www.wordplays.com/p/index