Thank you so much for responding. Unfortunately because I was a new member this question was delayed quite a bit and he has already been tested. As it turned out the school used the RIAS-2 and the WJ-IV ACH. We just got results today and unfortunately they don't clear up the questions I had, though admittedly my questions were probably not the same as the school's.

The results on the RIAS-2 have a note about the final subtest that says "would rather skip the item than potentially guess incorrectly. Due to the difference between scores on the Nonverbal Intelligence Index (NIX) subtests, the NIX composite score should be interpreted with caution. Additionally, the Composite Intelligence Index (CIX) may be lower than expected"

The school is looking for guidance on grade placement, while I wanted to get a better granular understanding of things like working memory and processing speed which the test didn't give. Also because of the one subtest, the score may exclude him from gifted services at this time which is disappointing. The VIX was 99.5% with a 139, but the NIX came out to 70% with a 108, for a CIX of 127/96% with a district cutoff of 98%. The T-scores on the 2 subtests for the non-verbal were 80 and 31, so definitely a huge discrepancy.

Meanwhile his achievement scores are pretty much about what I expected. 142/99.7% broad reading and 145/99.9% math. The applied problems subtest hit >160/>99.9% (which one would expect would require exceptional non-verbal skills!). All the achievement subtests were >99%, except one which was 92%. And this is a kid who is entirely self-taught. He loves learning and could read as soon as he could talk - but resists being taught. The school has already grade skipped him, but his performance is ... well, can best be described as missing. He says school is boring and he seems disengaged.