Hi- I just recently been diagnosed with ADHD inattentive type. My youngest son we think has it having behavioral problems in Kindergarten but better now at school. He does very well academically but in kindergarten he was completely bored and overstimulated which we understand now. He loves to learn but bored easily if he is not stimulated. He is very physically active and we have him in several activities which helps. Myself never acted out and did okay in school but had to study really hard in college and only focus on school and running. I was quiet, spacy but very physically active as well. I also have a son who has high functioning autism. Again he is excellent academically but does not socialize with other kids. He spends his recess reading books in the library. Anyways, so I don’t think you have to have trouble in school to have ADHD from my experience. Hope this helps.