I'd recommend taking a look at the Davidson website database for some really good articles on this topic and on preparing for discussions with schools. In particular, we had good luck reviewing (we took printouts for them and pointed out highlights) the concept of asynchrony. We have found that is something that educators grasp once it is explained a bit, in terms of why immaturity isn't a reason to hold back a gifted child's education.
Assume you have already been to the state of Ohio's site about gifted education? I saw some good case histories there, might be worth printing those to share.
Good luck!