I've done it and recommend it highly provided the Apple store you're going to has a highly qualified instructor. Since I wasn't a newbie to Aperture before doing this I politely insisted on interviewing the on site Aperture guru at my local store. Didn't take 5 minutes for me to know I could learn a LOT from her... she'd been working intensively with the program for well over a year.
A colleague had lessons from an Apple 'Expert' at my local store and he commented it was a waste of time, as basically the chap was only one lesson ahead of him and was simply regurgitating what he was taught the week before.
You need to be a experienced user of the programme in the environment it was designed to be used before you can teach it well.
Too many people teach software/write books on how to use software, because thay aren't actually good enough to use it in the real world. This doesn't mean an expert at using a piece of software is a good teacher though, as teaching is a another skill again.