Did you ask the tester if he/she thought that the achievement scores were in line with the IQ scores - in other words, would he or she expect to see higher achivement scores. That might get to if there is something else going on with that lower PSI.
My DS has a similar spread in his VIC/PSI and he has always been really slow (both #s are a little higher than your DD). Also, he would not have sat and done 40 problems at one time at age 7 and likely would not now at age 10.
One other thing to think about is the rigor of the work she was doing – was it 40 problems that she has known how to do for 2 years or was it something that stretched here. My DS does better on above grade level testing but his performance on state yearly grade level tests has decreased the last few years – he simply cannot maintain focus for long periods on work that he no longer needs to practice.
BTW, my DS did grade skip and was later diagnosed with ADHD. He is in a self-contained HG classroom and is still not being exposed to curriculum at his level on any regular basis.
