I agree, and I think even 13 is young. But, it's not something my girls are interested in and since they don't go to school, they are unlikely to feel that peer pressure. I don't wear a lot of make up so that message won't be coming strongly from me.
But, I would want to do everything possible to make my daughter feel good about herself. If that means bending a bit so she can feel she fits in with her friends, then I would help her learn how to wear make up tastefully and set some pretty firm boundaries in the beginning.