psyche, I'm in the Atlanta area (west side though), and I was having these same issues prior to DS5.5 being in K. He's in K this year. For us, we were EXTREMELY lucky for DS to have gotten his teacher this year. She's actually the one that suggested whole grade acceleration for him, which if requested by the parent in our county, the school has to at least go through the process. But of course, it's only required when a child is in K and in our county (as far as I know).

Have you tried contacting your school district, instead of just the school? What about the state? Though I'm pretty sure that Cathy Cox won't help much. Also, apparently, almost all GA schools are "needs improvement", and I know in several counties, you don't have to be in a "needs improvement" school to attend another school within the county so check that out as well.

If you are near Gwinnett, you might want to contact Spomenka Newman. We've never had DS tested by her, only because the $$ and the fact that she's over an hour away from us, but she HAS been extremely helpful just answering a few questions for me. Dr. Newman

And finally, try and contact the Georgia Association for Gifted Children. Our county's chapter is for the birds, but I was able to find a really great contact who has helped me out tremendously - she's local to me, but maybe there's someone in your local chapter or in the GAGC itself that can help.
GAGC Link

You can send me a private message, and I can see if my county contact might have a county contact for you as well.

I've actually thought about calling/writing one of the local news stations to see if they could help out, but for now, DS5.5 is on the right track.

Good luck!