I think my Montessori teachers did a great job. I don't have much love for the public school model but I was a special case being put up several grades and not being familiar with that teaching style.

I don't think I would recommend putting an 11 year old into high school early. Better to be an A+ student and have peers your age than take on a heavier burden to scrape through with Cs.

I have some friends who went through the entire steiner school model and they seemed fairly happy well adjusted adults. So I think yeah, if the model is working stick with it until uni.