Addressing #1, I don't think you could call it "common", but I have seen it with my son. His MAP was 99th percentile, but his FSIQ was 108? 106? Something like that. GAI was 117. Turned out he had ADHD and after his ADHD was treated and he was retested with FSIQ of 132 and GAI of 141.
I would suggest that there is a valid reason for the discrepancy - some deficit somewhere that affected her test scores. I believe it's worth looking for it. As she gets older she's likely to become frustrated with the extra hidden struggle. Students like this easily fall through the cracks without a parent advocate.
