This post literally made me tear up a bit. This was EXACTLY the situation DS8 was in for the past two years. Last year's teacher, after months of meetings in which she ignored everything I said, finally decided to give him differentiated math during the last month of school - to her, that meant giving him slightly more difficult worksheets that were still too easy for him, but making him do 80 or so problems PER NIGHT. The intention may have been good, but I have my suspicions that this was her way of trying to overwhelm him and make me shut up about the whole business. He was so shy and introverted, I was afraid to homeschool him for fear of him completely cutting himself off from the outside world. The minute I got the letter this year, saying who his teacher would be, I scheduled a meeting with the teacher, guidance counselor, and the AIG teacher for the school. (They don't do official testing for AIG until January of third grade, but she does limited work with certain kids who are not technically eligible for the program yet, if their teacher recommends it). I walked in with a notebook full of materials - everything from samples of work he has done over the summer, to research on gifted children, to his birthday wish list, where he asked for a history book and a graphing calculator. I also made sure I brought, DS, who made his own case ("I want to be an engineer and an astronaut, but I'm afraid I won't be able to get into MIT if I don't do more than basic addition in math class!" - his words, not mine).
We talked about his sensitivity and anxiety issues (apparently very common in gifted children) and how he does far better in a structured environment - in other words, putting him on a computer so he can teach himself advanced math is probably not going to work. We talked about how if this was a child with a disability, they would do everything in their power to help. And I politely informed them that if my child is not learning new material in school, then the only reason for him to be there was as a tool to boost their average test scores - which was completely unreasonable. I stated all of this while ensuring them that I was not making judgement on the job that these individuals would do during the year, but rather making a preemptive strike based on the behaviors of others in the same school, and made sure they knew that I was optimistic that this meeting would help, not assuming it was a waste of time.
We are only a week and a half into school, but so far it seems to be working. He is coming home with work that is not overwhelming for him, but makes him think. That is all I'm asking for, and I'm hoping it will continue. Anyway, I'm rambling, but I think the two important things are to involve everyone in your conference who you think MIGHT have some input - even last year's teachers, if you think it will help. And bring evidence. Everything you can get your hands on - I think what really made them wake up and pay attention in my son's case was that he was doing prealgebra in second grade. It wasn't perfect, he had made mistakes, but he was learning it - that was the important part.
Hope you find a good solution for your daughter!