When your dd was tested by the school last year because she was struggling with reading, did they do any other type of testing to determine what the challenge was re reading? Did they find anything? I have two dds who struggled with reading for different reasons - both of which impacted their scores on IQ testing - for my older dd, the challenge was related to visual processing, and the impact on her IQ testing wasn't reflective of her true IQ but the impact of not being able to see well. For my other dd, the reason she was struggling with reading was due to a true discrepancy in abilities that's accurately reflected on IQ testing. My kids have also been screened for dyslexia, and that involves more than IQ testing.
It's not true that children with high IQs can't have learning disabilities - two of my kiddos have high IQs and learning disabilities. It's also not true that kids that have high IQs can't have strugglings that impact their learning that *aren't* learning disabilities (for instance, my dd with the vision challenge doesn't have a learning disability but she was unable to learn how to read fluently until her vision challenge was resolved). What is a somewhat common experience among families with kids with challenges is that the testing provided at school is not as thorough as what you will get through private testing, and you usually get a more thorough explanation of the testing and what it means through private testing.
It would be interesting to see what each of your dd's subtest scores were on her original IQ testing. If she maxed out "a few subtests" then she must have had average or below average scores on a few too - it might help to know if the discrepancies in scores on last year's testing matches the discrepancies on her CogAT.
I'm not familiar with the ITBS, so I don't know what the mean & standard deviation are - so I can't tell you how her achievement measures up relative to her abilities. I can tell you that if you see lower achievement than IQ it *can* be a flag indicating some type of challenge, it can also be that the achievement scores aren't accurately reflecting your child's knowledge due to some type of challenge (for instance, my ds has a handwriting disability, so any type of timed fluency test that requires him to answer using handwriting does not match his ability to correctly answer the same questions in the same amount of time that he is able to if the test is given orally). The lower scores might also mean that on the day the achievement test is given your child wasn't feeling well or was distracted or daydreaming or whatever. OR - it might mean your child has a learning challenge of some type.
So - in brief, you don't know for sure at this point in time what's up with the achievement scores. You do know that your dd had some struggles with reading early on. You know that the IQ/ability tests she's been given have discrepancies and scatter among subtests (this can be a red flag for LD). Given all of that, I'd be in favor of having more testing to try to understand what's going on.
Best wishes,
polarbear
ps - fwiw, I don't necessarily agree with the school that the gap on the CogAT isn't a big deal. It might not be, but many of us with 2e kids have similar gaps, and they are in fact sometimes indications of something
