If I had known when I was rather younger, I probably could have done much better in school, and would likely have been a bit more successful–in many ways–than I have been.
I did great in school. Maybe I would have accomplished more after school. Good diagnosed in my mid 30s.
I did great in art school, because everything was working with my hands, and still required a high degree of thought/creativity. I did terribly when I was in school for engineering (prior to art school) because I just couldn’t focus on calculus and physics, even though it shouldn’t have been that difficult.