. I have a personal experience in this. My brother(small) started playing guitar during his 1st grade and presented some songs on the school on the 2th grade itself with his plucking skills. That was infact amazing, since i thought , by the time he grows up , he would grow skills as someone like yngwie malmsteen ;) . BUT , he started playing less guitar by the time he reached 5th grade and started DRUMS. He started it quite good, it seemed he knew what those beats are, what harmony is and how to roll your sticks! He simply plays superb and innovative scales. Man, we used to have quite good jam session and he still has a local band in the hometown, quite a punk , quite a rock band! :P Its fun playing music, it always is!