Encouraging a child's independence is deeply rooted in the Montessori Method - one of the reasons I love it.
Beginning with the very young children (3-6 year olds), students work individually on materials which develop their senses and motor abilities and their independent powers of observation, analysis, and integration - the essence of reasoning. Group work is not encouraged for the very young, who are just forming their minds, as it is in Progressive schools. However, children can work together if they want to.
Furthermore, well-trained Montessori directresses are very respectful of individuals, their styles of learning and living, their interests, and their ideas.
(We call Montessori teachers "directresses" or "directors" because they more guide the children than instruct them, the materials do the instruction).
Group work become a bigger component of the curriculum as the children get close to adolescence; as students develop, they need to learn how to work with other people to prepare them for adult life.
However, the children are encouraged to work at their individual best: not compete with each other. Human beings are naturally competitive, but it is very distracting to develop self-motivated learning habits when competition is emphasized, especially for the very young.
The ugly head of social pressure rears up to tear the young mind and heart away from the inherent joy of learning.
All these elements serve to encourage even the most timid child to be independent in their thoughts and actions, a welcome respite from the kind of social pressure I talked about in my previous post.
That's not to say that Montessori schools are immune to social pressure - I've seen plenty of teachers promoting their scientifically unsubstantiated or unexamined views on the environment and nutrition, among other topics, through special projects and lessons.
Fortunately, the many aspects of Montessori which encourage factual observation and reasoning mitigate against this.