I had a good impression of "Montessori" from hearing that Larry/Sergey/Bezos went to one. When I put my kid in it at 3 years old, he hated it. As I looked into it more, it seems to me that it is actually very rigid, with kids being able to play with just a small set of toys that don't really exercise their creativity, and with little opportunity for group play. We switched him to a Reggio Emilia school where the kids are constantly doing group projects and art and he enjoys it a lot more. I recommend parents observe what's actually happening in classrooms and think about what's best for their kid in the early years instead of assuming "Montessori" is the best path.