<p>My own jazz musician son started out on the trumpet and switched to guitar about age 11, and is now headed to a conservatory for jazz guitar. My son had a fun silly trumpet player as a teacher when he was in fourth grade, and I think he simply learned that music is fun, which is a great lesson. If your son is truly mature enough to handle serious music study, you could check out The Manhattan School of Music precollege program. There are many students from Westchester who go there on Saturdays.</p>