I'm sorry and I agree with the others that not accommodating his speed issues seems unreasonable. My oldest, age 11 and grade accelerated, has speed issues as well. She's isn't slower than the avg 11 y/o; she's just a lot slower than her other abilities. While we haven't sought time accommodations on things like the SAT (and she didn't quite finish her essay as a result), she does have an accommodation for extra time written into her ALP (accelerated learning plan) at school. It really only comes into play for her on timed tests, but in those few instances where she has needed a few extra minutes, they just send her elsewhere to finish up.

Honestly, I'd be concerned overall that they don't understand asynchronous development and might not do the best at meeting his needs if this is their response to his speed being normal for age while his intellect is much beyond his age.

Do you have any homeschooling cooperatives locally if you wind up continuing with homeschool until he is old enough for the Davidson Academy? Maybe something structured like that could meet his desire to be in school for a while.