Let me prefix this with the info that my DD does not go to a Montessori school but I'm confused by your post. I thought the draw for many was the fact that Montessori schools do groupings? IE 3 - 6 year olds are in class together. From your short description of the school, I question if the school you reference is a true Montessori. But again ... my knowledge is from the outside since I have no experience. We did consider it for my DD and I called and talked to a few schools in our area and what I could tell is the certified schools are more strict. For example, if you wanted to send your child part-time it would have to be for a minimum of three consecutive days such as MTW or WThF because they work on projects and missing a day would be disruptive.