Hi Scrimmy!
Don't take lessons just to learn the barre. It's only (ONLY!) about trainig and training some more. The teacher can't do much for you but hand you exersices that you can find in a book or free on the net. Only on this site there are loads of tips, and there is billions of guitar sites out there...
I'm not against the lessons, just don't go there thinking they will magicaly teach you the barre in no time.
As for your son I would suggest you check if there is any group classes. They are often less expensive and the kids gets the chance to play in group (and maybe get some jam-buddies to start a band with <img src="images/smiley_icons/icon_biggrin.gif" border=0 alt="Very Happy"> ). Mostly you pay a fixed prize for say 10 lessons in a row (once or twice a week).
I myself (soon to be 40) signed up for a rookie group class. We are 5 + teacher (i'm oldes and the youngest is around 20). The funniest part is when the teacher "ensambles" us, giving some of us base-lines, others harmonics and himself soloing. Great fun and astonishing enough it sounds really good. For 10 lessons times 45 minutes I payed 650 Swedish crowns (should be around 50
If you love what you do, there's no need to be good at it...