Basic Cozy Spelling is a free complete spelling course geared to 6th through 8th grade. It is provided online complete with course description, spelling rules, dictation, and 30 lessons. Sponsored by Splashes from the River.
SpellCity.com is a really cool site that allows your child to enter their spelling words, drills them (voice recitation as the letters appear), and then play games like hangman with their words, and then take a spelling test with those words. Fun!