http://www.sfskids.org      Who:  Awesome site for kids of all ages.    What: Interactive music activities for Discovery, Listening, Playing, Performing, Conducting, and Composing.    http://www.keepingscore.org/interactive  Who:  I would recommend 10+, but I would let your child try anyway.  What: Another excellent site by the San Francisco Symphony (interactive site for info about composers and more)  http://www.openclassical.com      Who:  Awesome site for any age  What: Learn about composers and listen to their music.  http://dictionary.onmusic.org/      Who:  Any age  What: Learn about composers, time periods of music, and play music by composers.  NOTE: If you click the 'Instrument' page, please view by 'Western Symphonic Classification'; otherwise, your child will not have a clue what they're talking about.  http://www.favorite-classical-composers.com/    Who:  Any age  What:  Biographical info about composers