We paid about $500/month in Springfield, Oh. Our son now attends public school but comparing both, the Montessori has incredible skills to teach Math and Science. The kids get to choose their schedule (the order in which they want to take their individual classes) and they promote self motivation for learning versus the traditional idea that "you go to school to learn because that's what you have to do." The only con was that kids do a lot on their own so it made it hard for our son to work in group projects at public school. He also had problems making friends at the Montessori (and he is a very social kid) since it was a very small school and the kids knew each other since they were 18 months old and would stay until 3 pm. My son only attended until 12 pm and he would constantly mention that kids wouldn't play with him because they already "had friends." Although he was learning sooooo much, in our experience he seemed a little bit unhappy due to the social aspects. Once he started Kindergarden at a public school, that dissipated quickly and he started talking about his best friends and he seems to be very happy. This might not be the situation in every school but I think it would be important to look at any signs to make sure that your daughter is also happy, not just learning a lot.