High school Special Education teacher here - Montessori is student centred as some posters already mentioned and this means that students learn at their own pace in a level that is suitable to them. I actually use many Montessori methods with my learning challenged high school students because it's the best way to learn! I have studied this extensively, and so I can attest to the fact that I usually have 20 different brains in my class at any given time; therefore, if I make them all do the same thing, at the same time in the same way, there are going to be problems. Montessori teaching allows for self growth and emphasizes "freedom within limits," and that unfortunately for children, clashes with the traditional school system.
I must admit though, for us we embrace the Montessori philosophy because we believe it, and totally understand it. Many people though, have no idea what it is and think it's just daycare (I've been having this argument with my MIL for 2 years now!). Therefore, if parents are just looking for daycare, then they should go somewhere else as those parents who really believe in it are usually fighting to get there children registered as there are usually lengthy waiting lists for most Montessori schools in our area as they are all private - no government assistance or subsidies at all. Please no flames here, but this really irks me as parents just want to jump on a bandwagon that they know nothing about! I'm not sure why you'd want to enroll your child in a program that you know nothing about? I guess that's a discussion saved for another day - LOL!!
My DD started full time, 5 days per week at 1.5 years old in Toddler room, she just moved into CASA level (3-5 year olds) at before 2.5 years old. She is the youngest in the class, and is very sharp, extensive vocabulary, etc. Would she be this way if she had not gone to Montessori school so young? In our case, more than likely as I'm a teacher and our home is Montessori designed - things at her level, chooses her work, child centred, etc. At this stage, she is already doing work that her neigbour friends down the street are doing in JK and they are 4 years old. In our district (Canada), you are placed in the age appropriate (that's the problem with traditional school) grade level; therefore, she is not going to be attending her Catholic school (even though it's my own school board) for some time as she would be beyond that work as she is already doing things that students twice her age are doing. The transition phase from Montessori to traditional classes (if there is one, as many Montessori schools go to high school) is very important.
Our Montessori school is the best in the area - amazing teachers and the principal is out of this world - that means a lot coming from me since I am very strict about these things since I run a high school Special Education dept. myself. We pay approx. $800.00 CDN per month (summer is extra) and it is well worth it - my DD loves school and my hubby (my nieces and my best friend's DDs attend same school as well) and I coudn't be happier!
Tiger