My daughter went to a Montessori school here in Canada from 18-months old until high school. About the class size... As a Montessori class has students in thre

My daughter went to a Montessori school here in Canada from 18-months old until high school. About the class size... As a Montessori class has students in three different year levels together (e.g. a Casa class would have children aged 3, 4, and 5) and part of the philosophy is for the senior students in a class to assist in teaching the junior students, the class has to have a sufficient number of students in order for this approach to work. Small class sizes don't have enough students to support the learning model. In my experience 27 children in a class is very typical and not at all an over-populated class. I've seen larger classes work just as well. The Montessori school my daughter went to would have a director/directress and an assistant in each class.