Welcome Lisa,
What a tough decision you have on your hands!
On one hand a FSIQ of over 145 on the WISC is incredibly rare, it would be difficult to meet the child's learning needs in any situation, but it sounds like your school is trying and that she is happy. Great!!!!!!!
On the other hand, if she refuses the skip, my opinion is that a one year grade skip doesn't magically solve the problem. Most kids at that level will catch up to the next grade kids incredibly quickly. If she is miserable with her new classmates, it might not be worth it.
MHO...I'm sure others have evidence to the contrary.
Good luck
