Thanks everyone
polarbear - I think you are right. I was considering a full evaluation, I was even thinking of waiting until he is 6 so that he could do the wisc as the wppsi did not have a section specifically for working memory.
I have been hesitant to think too much about ADHD as there is so much overlap with gifted behaviour traits, but if reading comprehension is going to be an issue, that is best addressed earlier as it will have effects across all of his education. It is not a huge issue this year, and I can see the school not even taking it seriously as he is in kindergarten and reading at a 1st grade level. But the teacher said as soon as the test went beyond the level with picture support, he struggled to answer closed questions. So it sounds to me like there is definitely something going on, be it ADHD or something else. He is very bright verbally, he is able to read with the accuracy/fluency of a fourth grade student, surely he should be able to comprehend at a level higher than 1st grade?
some google searches on adhd and reading comprehension seem to say it is a common symptom and some of the signs were things DS does, like skipping words, substituting a different word with the same meaning, and reading very quickly.
