I have a dd who has an issue impacting reading that was really difficult to see for a long time and that didn't show up as obvious on tests like the WISC etc. Like your ds, she had no issues with comprehension when another person read *to* her. Instead it primarily showed up as underachievement in reading progress at school. What helped us tremendously was seeing a reading specialist for an evaluation. The reading specialist had a long list of tests that she ran (I can look them up for you if you're interested). One thing you might try at home is to have your ds read out loud *to* you - that might be really telling. See if he trips up over any words, are they complex words or simple words etc. Does he track ok from line to line, does he resist reading out loud, does he fatigue quickly etc.
Best wishes,
polarbear
