My son is in a Montessori class for 3-4.5 year olds. From my research and talking with his teachers, "Montessori" schools can vary greatly in their idea of what "Montessori" means and how they apply it. I enrolled him at their other program at 2.5 because he was obsessed with puzzles and preferred puzzles over friends, which was new and I knew that he needed somebody/something other than me to teach him. I was so full of anxiety, I was sure that he would have tantrums all day, they wouldn't understand him, etc. Wrong! They totally get him, they recently had a PG student and his behavior couldn't be better at school. When they are learning, they are happy! It's all about you feel about the teachers. Also, in the first program we were in, it started too early in the day and he would basically have an anxiety attack for 2 hours before school and I could not get him ready. Once he was there, he would run in happily, never cried. But that time was just too early for us, after a few weeks, I couldn't take the 2 hour battle to put pants on, I was emotionally spent and wasn't sure any of it was worth it. Now he goes at 10:30 and that gives us plenty of time to do our morning routine and get him in the car on time.