Cym-
I've actually been surprised at how many letters ds13 has needed already. He has applied to several summer programs and such that ask for letters of recommendation. I imagine that by the time he applies to full time college (whenever that will be!), he will have newer, more impressive recs. It just doesn't hurt to ask now, and it can give you a window into what the teachers observe. I wouldn't ask for no reason, but if your son is going to apply to any programs, it is useful for the instructor to have specific examples to refer to in a letter, rather than, "Oh yes, I recall that he was a good student."
Some programs require you to use their form, but if the teacher has a letter on file, s/he can tweak it to fit the bill.
