I don't have the report handy, but my NT child had virtually identical scores for the GAI, FSIQ and the indices. The tester said it was a totally normal pattern in very bright very young kids, and it's why they have the GAI. Any formal program should take the GAI as the IQ score. The lower PSI she said was accounted for with slow writing because they're young, so it wasn't even an area of weakness. She also said that hestitating due to perfectionism was there, but is also common.
Age equivalents - the 18 and 19 scaled scores are 16.
Under achieving, you can't really tell from that. She has a high ability, is she being asked to use it?
And yes, you should get them to calculate using the extended norms
