DD10 has been in a Montessori school since Toddler House (2-3 years old) and we have had some awesome teachers and some terrible ones (no exaggeration). One thing that has been pretty constant, though, is that it seems like there is less communication from the teachers about exactly what the students are doing than in regular schools, although there are periodic 'bring your parents to school' days when we get to see more detail. This can be really confounding when you are trying to sort out exactly what your kid is doing and whether the teachers are really trying to make sure your kid is challenged while also learning topics thoroughly. Also even the great teachers we have had were not constantly introducing new things--DD might get a new lesson every week or so, depending on what else was going on in the classroom. So it was not the kind of acceleration that one might expect based on other school environments. As long as DD was happy, we were happy.
You mention that your DD often says she doesn't want to go to school--has she explained why? Is it because of the material not being challenging enough, or something else? Do you think she is asking for more material at school and is being disregarded?
My understanding of the Montessori philosophy (although schools differ widely in implementation IME) is that they will move the child ahead when the child is 'ready,' which may include I think emotional readiness. The school recruitment pitch often includes saying that kids will get new material when they are ready for it, which I think many parents (us included) take to mean something a little different from what the school means and from what the teachers actually do. Our DD was not allowed to go to the Upper Elementary classroom for more advanced math lessons in 3rd grade, we were told, because her behavior would have been disruptive, but neither did her own teachers that year make an effort to give her more challenging material. In contrast, in 1st and 2d grade, her teachers (different ones) always told us how much they enjoyed teaching her and often gave her lessons with the older kids in her class and even some by herself, but it wasn't even every week--although DD loved it. Over time, we came to consider these teachers to be at opposite ends of the teacher spectrum (based mostly on other stuff), but at first it was difficult to tell exactly what is going on, especially when it was a new school or a new classroom. And our DD has never been a very reliable reporter of what goes on in the classroom so that wasn't much help.
What does the teacher say about your DD? It seems possible from what you said that she thinks you are being a 'pushy parent' who is trying to force new material on your DD that your DD isn't ready for, so I second Madoosa's suggestion and talking about anything your DD says or does at home that might support her interest in more challenging material and making sure the teachers understand it is coming from your DD and not just you. Good luck!
