Dr. Montessori's research and observations led to extravagantly detailed information about child development. The charts are taken from her book, The Absorbent Mind, and offer an explanation of the various skills children develop from birth through two-and-a-half years old.
Dr. Montessori described child development in four phases or planes. Each plane is represented by a triangle and includes six years. For the sake of early childhood, our hearts are set on her first phase of infancy, in which the child gains specific skills from 0-3 and refines them from 3-6. *Factoid: the arrows used to represent movement through each phase are the same ones used in the Move Mountains with Montessori logo to show transition among each mountain!
A word about sensitive periods...
There are many phrases coined as "Montessori-isms," and sensitive period is the Grand Daddy! Think of it like this: a sensitive period is a window of time when a child is not only primed and ready to acquire a skill but s/he is so excited about the new skill that the only satisfaction would be to practice it over and over and over and over. Warning!!! The window of opportunity is temporary. So, it's ever so important to watch for it and allow ample chances for it to flourish. Sometimes a child is in simultaneous sensitive periods.
Birth to 3 Years old
Order, Language, Movement
While offering plenty of access and space to explore and manipulate the environment, these young children need to understand what they can do. Creating realistic spaces (as opposed to kid spaces) with objects and furniture for their size helps them understand more of the surrounding world without someone constantly telling them "no!"
Toileting: Believe it or not, children can and should practice toileting before the age of 3! Their bodies are primed and set to go through a sensitive period for toileting, usually between 18 months and 2 1/2 years old (plus or minus some months on both ends).
three to 6 years old
Language, Refined Movement, Sensory Exploration, Mathematical Concepts, Socialization, Order, and (a personal favorite of mine) Minutia
These children have more comprehension and more words! Modeling and briefly speaking expectations before hand is key. We pave the way for success. On the other hand, WHEN things go array, give natural consequences rather than punishments.
Grace and Courtesy: If children do not learn and practice good manners and how to positively interact with others/the environment by the age of 6, the ship will sail, leaving them to be primitive Neanderthals FOREVER!!!
reality vs. fantasy
Children from birth to 6 start with extremely concrete concepts, moving towards abstractions as they develop. For this reason, it is difficult for them to distinguish between reality and fantasy. Instead, their brains are wired to tell them that what is seen is reality, even if it isn't. It is so important to set a boundary with unrealistic experiences (although most consumer products and television shows geared for children will tell you otherwise). This is why children absorb the characteristics of what they see, trying them out on themselves and their peers. Have you ever seen a child pretending to be a violent superhero with her friend, not realizing that her behaviors are not appropriate and endangering? This is my case and point. Wait until they are past the first plane of development to introduce fantasy. Trust me, it will suit them (and your sanity) much better.