Music
http://www.playmusic.org/

San Francisco Orchestra for kids
http://www.sfskids.org/templates/instorchframe.asp?pageid=3

Lead a Jazz Band
http://pbskids.org/jazz/bandleader.html

Play an African Thumb Piano
http://pbskids.org/africa/piano/haveflash.html

Global Groovin
http://pbskids.org/mayaandmiguel/english/games/globalgroovin/game.html