Sorry to hear this. How frustrating. Last year DD was considered the slowest in the class and now none of the teachers see her as being particularly slow and she's with kids who are much more advanced than last year. So what changed? The level of the work is the biggest thing I can think of. Either that, or her medication. Does your DD have an explanation for why she's slow? Or is it that they're totally making it up?
We had this sort of situation with DS last year, where the teacher seemed focused on proving he's not really as advanced as we thought. She completely disregarded the WISC, Woodcock Johnson Achievement, etc. Now 6 months later he is scoring like an average 9th grader for math in second grade (on the above-level test the school district gives). Somehow I think she'd figure out a way to even dismiss that. With these types of people it is useless to argue, I'd just figure out a way to get out. They are never going to admit "Oh, ok, I was wrong, she really IS quite advanced so here's what we're going to do to get her challenging work." They are going to ignore all evidence that is contrary to what they want to believe.
