I want to reiterate what gratified is saying. Schools, for the most part, are not interested in IQ numbers. I suspect that your efforts to get accomodations for your child will fall on deaf ears so long as you focus on IQ.

What schools care about (when they do care) is what your child knows. But even here, testing on the school's own curriculum (using their end of year tests) will be far more persuasive than simply showing scores from an achievement test like the WJ-III or the WIAT (or even a talent search test like the EXPLORE). If I were in your situation, I would ask to look at the curricula for the classes in question, and ask if your DS can take a test to show whether or not he has mastered the material.