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His cognitive scores would suggest that math should be an area to consider for advancement, especially conceptual math, but I would guess that the school made the placement recommendations based on his WIAT-III achievement scores, or on curriculum-based end-of-course testing, not purely on his WISC-V scores. And, depending on your district's curriculum and in-class differentiation options, as well as the profile of the overall population, they may feel that they can accommodate his needs in the regular classroom. It's hard to say without knowing where his actual math skills are at this time.
