http://teacher.scholastic.com/activities/bll/index.htm Scholastic provides three games to improve spelling skills. Leo Loves to Spell ( students help Leo find the correct letter ), Reggie Loves to Rhyme ( Rhineceros needs help finding the the words rhyming with different objects ), and the third one is called Nina the Naming Newt which also needs help identifying objects that belong to various places.
http://www.spellingcity.com/ This is a website for both spelling and vocabulary practice. It includes more than 42.000 spelling words and takes into consideration the spelling differences between the American and British English ( colour/color, favourite/favourite ). It also provides the correct pronunciation of every word mentioned there.
http://www.spinandspell.com/game.swf A spelling and vocabulary-building exercise site. Images and audio are provided, and players select the categories they want to use. It doesn’t use the words in sentences.