Ricci Adams' Theory website This is a great website to help students learn notes, key signatures, intervals and ear training. Each exercise is customizable. (iPad app: Tenuto)
iPad apps: My Note Games (play it, tap it, and write it); Music Tutor (flashcard note identification), Piano Free (keyboard and metronome), AnyTune (practice app that can change tempo to any song without changing pitch)
PracticeSpot This website has musical crossword puzzles for all ages.
Music Mind Games This is a great website for flash cards and games for purchase. The Suzuki School of the Woodlands uses many of the materials in the Puppy Packet.