Planes of Development

1 Birth to six (infancy)
2 Six to twelve (childhood)
3 Twelve to eighteen (adolescence)
4 Eighteen to twenty-four (transition to adulthood)


Each of the four planes of development last approximately six years and is further subdivided into three-year segments. The first three years of each plane show the most dramatic change; during the second half, the child stabilizes. The first and third planes of development have some parallels and similarities. They show the most dramatic development, and have many needs. The second and fourth planes are also similar. They are healthy, stable, strong periods of development. The Planes of Development are the basis for the three-year age groupings found in Montessori school classes: ages three to six; six to nine; nine to twelve; twelve to fifteen and fifteen to eighteen.


0-6: THE FIRST PLANE OF DEVELOPMENT : Sensorial explorers / The Absorbent Mind


According to Maria Montessori, the first six years of life are the most important period of life because they are formative years. During these years, the child creates himself, both as an individual and a member of his society. To do so, he disposes of a completely different type of mind than the adult, the Absorbent Mind, which allows him to absorb knowledge from his environment (through his senses) easily and without fatigue, simply by living in it. Children in this plane are sensorial explorers; they teach themselves using their senses. The Absorbent Mind works like a camera; a camera can take a picture of one or several people without effort, while the adult mind works more like a drawing. Drawing requires time and efforts. It is harder and longer to draw one hundred people than one person.
The Absorbent Mind also has adaptive properties: it allows the child to acquire the culture of her environment and to become a citizen of her country. It is important to note that the child does not absorb from her environment passively. As we have seen, human development is guided by a life force or vital constructive energy, Montessori termed Horme. Bergson referred to it as “élan vital” and Freud as “libido”. This constructive life force stimulates and activates the individual drive to learn, to realize herself and to reach her highest potential. In the first plane of development, horme is driven by optimal learning periods Maria Montessori called Sensitive periods. They are nowadays referred to as Windows of opportunity, Critical Periods or Prime times. Sensitive periods are times during which the brain is specifically efficient at some types of learning. Sensitive periods manifest themselves as an irresistible attraction to some aspect of the environment (people, language, movement…). During a sensitive period, a child can learn rapidly if the opportunity is provided. Once a sensitive period has passed, it will be harder and at times even impossible for the child to learn a concept or skill. For example, if a baby going through the sensitive period for attachment has not had the chance to bond positively with a caregiver, he or she will have difficulties creating attachment and relationships in his or her life. In the same manner, as Itard showed with the savage of Aveyron, if a young child is not surrounded by language during the critical period for language, it will be impossible for him or her to learn to speak later on in life.

First subplane (0-3): Unconscious Absorbent Mind

The first sub-plane is a period of great transformations, both physical and psychological and is characterized by the Unconscious Absorbent mind. The child absorbs everything in his environment without willing or knowing he is doing so. This also means that he is not yet able to filter or select information. The impressions absorbed (i.e. language and culture) become a part of his unconscious memory or Mneme. In the first three years of life, the child constructs his personality and individuality. Montessori called the child in this period a “spiritual embryo” to compare the child’s non-physical development (cognitive abilities, personality, character, emotions and social tendencies) to the physical development undertaken in the embryonic period. An embryo grows unconsciously directed by the vital constructive energy They also grow secretly, in the dark, and we can’t affect them directly but only indirectly, by providing them with an environment favorable to their optimal development.
An optimal learning environment for this age is a caring, nurturing and consistent environment which allows for plenty of sensorial explorations, in respect with the three main sensitive periods characteristic of this period: Movement, Order (including consistency of people and things), and Language. In preparing the environment, one has to be careful not to over stimulate the child since he is not yet able to select from his environment and to tune out from too much sensory stimulation.

Second sub-phase. Conscious Absorbent Mind

Children in the second sub-phase have a different type of absorbent mind: they still soak up knowledge from their environment easily and effortlessly, but they are doing so consciously. The child is now able to selectively choose from his environment. This shift from unconscious to conscious happens gradually as the child grows in independence and starts working with his hands. Children in this sub-phase want to do things for themselves and by themselves. They love imitating adults and taking parts in chores. It is important for the adults to allow them to do so.


6-12: THE SECOND PLANE OF DEVELOPMENT: Conceptual and social explorers/ The Reasoning mind


The second plane of development is a very stable and uniform stage. There is not much transformation. The child is stronger mentally and physically; she tends to get sick less often and has a tremendous amount of energy.
In the first plane, the child was egocentric as she was forming herself. In the second plane, she is genuinely interested in others and she becomes very social. The elementary years are marked by the “herd instinct.” The child’s social development is guided by “psychological characteristics,” which manifest themselves as a strong interest with issues of good and evil, right and wrong, justice and injustice, fairness and unfairness, etc. Children in this plane can not quite grasp moral and ethical subtleties. Because they respond to the elementary child’s interests in moral and ethics, Montessori recommended introducing fairy tales during this time.
The interest in social justice reflects the child’s different mental abilities to abstract, reason and imagine. The child in the second plane no longer has an absorbent mind, rather he has a Reasoning Mind. The child of the second plane of development is no longer content to be a sensorial explorer. Able to distinguish between fact and fantasy, he is ready to use his imagination and intellect for an immensity of work. Having established a physical familiarity with his environment, the child grows curious about its structure. From age 6 to 12, the child becomes a conceptual explorer. The child at this age is in his most intense period of learning, Montessori called “Intellectual Period.” Therefore, this is when the universe should be introduced to the child. Montessori designed a different educational curriculum for children this age; called “cosmic education.” Whilst the young child was given the world, Dr. Montessori saw the need to give the universe to the child of the second plane. It is based on five imaginative stories, called Great Lessons, that show how everything in the world is interrelated and how the universe and everything in it was created. This shows children that they too have a role in the universe and inspire them to contribute positively to the world. Maria Montessori said ‘Since it has been seen to be necessary to give so much to the child, let us give him a vision of the whole universe. The universe is an imposing reality and an answer to all questions. We shall walk together on this path of life, for all things are part of the universe and are connected with each other to form one whole unity. This idea helps the mind of the child to become fixed, to stop wandering in an aimless quest for knowledge. He is satisfied, having found the universal centre of himself with all things.' (To educate the Human Potential, Clio, p.5-6).
The five Great Lessons are
1) The Story of the Creation of the Universe
2) The Time Line of Life
3) The Coming of Humans
4) The Story of Language
5) The Story of Numbers