I'd have to agree with PP, I don't think it is harmless. If your DC already has the WISC scores, I'd inquire first, before having them take the CogAT. If the CogAT comes back lower than needed, some districts with limited space, might use that to try to keep a child out of the program.
It also depends on how high of a CogAT score they are looking for - this varies greatly.
FWIW, DD's CogATs and Wechsler tests (she did NOT take the WISC, but the Wechsler test selected and administered by the school), were consistent, with her individual FSIQ being higher than her CogAT score. As you probably already know, though, this has NOT been the experience of everyone on this board. The CogAT seems to "miss" many children who score very high on a WISC.
All our best to you and your DS!
