Have you asked yourself why your daughter blew this test? I mean, that is kind of bizare, do you think that she deliberately did not do her best? if this is a really gifted kid who wants to move on and work on academics far beyond her age level, I would be very hesitant as a teacher or administrator to offer a second test to promote her, and they may be thinking that it is all Mom, and not the child, if you know what I mean.
Here is the problem in a nutshell. It is really hard to tell if kids are "gifted" at this age. You will find that very many of the kids who seem that way as a 6 year old may continue to learn quickly through the lower primary grades, but by the end of 3rd, begining of 4th the differences between the early achievers and their peers, in very many cases, will be gone. Some of those kids will go on to be gifted at that point, and some of the kids who had a more typical pace early on will test as gifted. Testing at this point is most unreliable, sometimes because even smart kids cannot do their best every day, and what you may be seeing is a that view, a more typical view, from your new district.
Jumping two grades is very questionable, and enrichment is far, far better in nearly every circumstance than promoting the child beyond thier chronological range. If you think she is miserable, then I would suggest that you focus on that, and you certainly need to deal with the behavior, since children viewed as behavioral issues are also not ones that teachers think of for accelerated promotion.
She needs to learn to get along with her peers and that is a skill that is as important for kindergarten as any academic skill. Her peers are not 7 or 8 years old, even if that is her preference age. Getting along with an older or younger child is a very different skill than the give and take of what should be a more equitable balance of power sharing than what goes on between and older and a younger child.
Speaking as a person who deals with school districts frequently as an educational advocate, you may have created some of the resistance by coming off to the new district as a demanding know it all- I am not trying to insult you! It is a reality that parents have to deal with, even on the special ed side, if you come in and sound like you are telling them what to do, they may not listen to you just because they are put off. If you are a school offical, please don't blast me either, I have seen it over and over, and even really, really good people fall prey to this, it is human nature.
If you really feel like your daughter needs something more, see if you can re-establish the relationship with the school and find someone who will champion your cause. Find out how that district handles kids like yours, if that pot is empty, you may be chasing a rainbow that you don't want to find the end of. Work on her difficulties as they present themselves in her current grade situation, you may be there for a while.
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You left out critical information, and your subject title is a little missleading, both made you appear to be asking for trouble. You have less to worry about for the peer age problem, but I think I would still be cautious and be sure that before you consider promotion, that you are sure that she has not missed any critical pieces of instruction by skipping a grade. A lot goes on in First grade, even if they can read and ad. There are critical building blocks that you need to be sure that you do not skip.
As for what to do now, here is my suggestion. Go to the Georgia department of Education website and look up the grade level skills for 1st grade. In Texas, these were called the TEKS. This would be the criteria that Texas schools used to justify promoting her. In Texas there are several tests that measure aginst the TEKS, the most commonly used when we were there is called the CLAS. Find out what it is for Georga, and find a qualified person to do this test privately. If she flubs it a second time, she is not ready.
If she seems to sail through, and you are sure that she will not miss anything in the first grade ciriculum, then try again to re-establish the relationship with the school. My hunch is that how they viewed you coming in has something to do with it. It may be a long road.
Good luck
M.