aeh, you mention that the NNAT has a history of being more fair to diverse populations, but there is a study to suggest that english language learners scored more poorly on it than other tests. The study also found that the NNAT overidentified both extreme high and low scorers on the test. http://gcq.sagepub.com/content/52/4/275

This study was done on the original NNAT, not the NNAT2. I'm curious if the development of the new version has eliminated some of those flaws. The counselor at my son's school also mentioned that the NNAT2 was a more difficult test than the cogat, which seems strange given that they are both normed to an average of 100. His district is diverse (we live in Texas), so I'm wondering if that might have something to do with her impression, if indeed the NNAT2 underidentifies minority students in comparison to the cogat.

Sorry to derail the thread a bit, though it does point to the fact that these tests are imperfect. I would tend to trust the results of an individually administered IQ test over a 30 minute group test, even if the group test is more recent.