I always assumed that taking U courses early was REALLY REALLY extreme. But my mom just sent me some old binders from premed courses I took when I was 12. It never really dawned on me that I did U courses early, despite the rather glaring obviousness of busing out to the campus!
I was never accelerated in school, though.
How rare is it actually to do this? Are there a lot of non-accelerated teens who do it? (to be fair, it's not a totally random question, I'm thinking of paying a teenager with a summer course -- but I'm sure she can handle the U course as easily as the non-U course I'm considering, so the question is more out of curiousity...)