I'm a lefty who plays right-handed. Didn't start out that way. I coverted my own guitar to a left-handed one, but every decent guitar I ever saw was right-handed. No one in my limited world knew that guitars were built left-handed. So I switched. I've played that way for fifty years.

I agree with everything above *except* tunesmith. After fifty years, playing under stress (as in performance) is still limiting. My body and brain want to revert to initiating behavior with my dominant hand.

No, I've never seen a left-handed piano. Wish I had. I've never seen a left-handed piano accordian either, and I fiddle right-handed. The same stress problems show up on them all. I can make them all work (good thing -it's my job), but it is a labor and a drawback. And unnecessary in a world that does, in fact, include left-handed guitars.

The only reason not to play left-handed is that you can't play everyone else's guitar. For some, that's reason enough. For others, it is a small sacrifice.

I'm most comfortable on english concertina and whistle...totally even-handed instruments.

Here's a variation on jonm's test. Hand the kid a jar with a screw cap. The hand that initiates the removal of the cap - grabs it and turns it, while the other hand holds - is the hand that will initiate (pluck) most comfortably. Probably...

But also keep in mind what leeneia says. Every lefty doesn't naturally pick up a guitar left-handed. So that's your next test. If the kid already has a LH guitar, that tells you everything you need to know (unless it was gotten for him by some anxious, well-meaning person who didn't let him make his own choice).

And learning to play is just that...learning. I've had students switch (both ways) after a few weeks or months. As a player, you are learning as much about yourself as you are about music and about your instrument. It is a process.

As a teacher, don't sweat it AT ALL. Play and teach your way. There is nothing you need do except purge "left hand" and "right hand" from your vocabulary. "Fingerboard hand" and "picking hand" work fine.

If you enjoy teaching him and if he enjoys you and the guitar, believe me, in a few weeks
you won't even think about it.

Have fun, - George