My son was never diagnosed as ADHD, but one of my former teachers later became a substitute for one of his classes. She told me I should have him tested because he didn't sit in class. I didn't know it at the time, but apparently it was pretty broadly understood that Duncan did not sit in class. He always stood at the back of room. As I started asking questions the teachers all agreed he was very respectful and not disruptive so they let it go.
As I result, I read a book called Raising Cain: Protecting the Emotional Life of Boys — which focused a lot on the ways in which boys learn differently from girls to begin with and also had some great tips on dealing with a lot of different situations. I highly recommend it.