Hi M&M,
I offered some advice in a previous post:
http://giftedissues.davidsongifted....to_interpret_test_scores.html#Post222931which I would repeat if I hadn't already said it!
The other thing I'd add - what type of testing/evaluation was administered by the psychologist who feels your ds doesn't have ADHD? Has he had an educational eval at any point which includes achievement testing?
It's really difficult to say if this is "something" or just typical 7 year old behavior based on what very little we know by reading your post - the one thing I would add is that it's important to listen to *your* gut feeling as his parent.
Best wishes,
polarbear