Hand washing is the Montessori exercise that awakens the hands that awaken the mind. Watch the meditative expression on a three year old child's face as he stands in front of the water bowl soaping his hands, or when he places them back in the water bowl watching the soap as it wafts from his hands to the water's surface, and you will understand how powerfully the hands inform the brain. You will understand why the hand washing exercise is so important.
Then give a child a variety of appealing manipulatives. Include many conventional household items. These materials must offer increasing challenges for growing minds. And you have the physical basis of the Montessori classroom. No, don't look for them in your local toy store because, despite the fact that they call to children, few of them seem toy-like. They call to children in a more serious respectful way. Looking at them, working with them, a child realizes that he too can learn important things, that he too can be an effective person in his own way.
Without competent use of his hands, a child's intelligence cannot develop properly. Not being able to use his hands effectively preys not only on intelligence but on behavior as well. Some think that a young child who is incapable of obedience has no initiative. Or if a child seems lazy or sullen or sad, the cause is psychological. But there is a surprising cure. A child who has been able to work with his hands, using his hands to serve his own purposes, develops his confidence, his awareness, and becomes outgoing. As the hands develop, so does the mind. Intelligence grows with character when the hand grows the brain.
Maria Montessori discusses this in The Absorbent Mind, chapter 14, “Intelligence and the Hand.” She also discusses in this same chapter the child's developmental need to walk; and as soon as he is able, his need to walk while carrying objects of his own choosing. She cites examples from anthropological history that inspired her thinking. So she wisely set up her classrooms to serve these biological needs of young developing children. Here a child walks about the classroom to select an activity he wants to work with. Then he carries it to a table, or if the selected work is large, he stops first to place a work rug on the floor.
So today right here in the USA, there are wonderful Montessori schools with remarkable, effective, children busy learning to be interested in everything around them, learning what their relationship is to their environment, and learning how to effectively interact with it and with each other. Shouldn't all children have this opportunity?