HowlerKarma, I did something somewhat similar in college (I negotiated my way into a second semester German course despite never having had any previous German). It really wasn't difficult (despite the college being quite selective) and I'm glad I did it. From my perspective now as a professor, though, I see a lot of students who try to take things without prerequisites and then don't succeed. It can be a very difficult judgment call and I think it helps to illustrate why being able to realistically assess one's own abilities is so important.
My daughter is currently working on math with a tutor and it has been wonderful for her. She gets really intimidated and doesn't want to try the work because she is used to basically just doing calculations in school and these problems require her to think. Despite her reluctance to do the problems, though, she loves working with the tutor and it is her decision to continue. I'm very grateful the opportunity came along.
