Dr. Maria Montessori laid out the four planes of development which are 6-year spans of growth: Infancy, Childhood, Adolescence, and Adulthood or Maturity. Each plane of development has a unique set of characteristics. Growth will happen with favorable conditions that support the needs of that age individual. The first plane of development is characterized by the absorbent mind from birth to 6 years old. The second plane of development is characterized by intellectual growth supported by the imagination and emulation of others and peer relationships. The third plane of development is a time when the adolescent needs to be treated more as a young adult than a child. Lastly, the fourth plane of development is a period where an individual is a full member of society with moral obligations.
An Overview of the Role of the Planes of Development
Dr. Montessori discovered that human development isn’t linear and that it happens more broadly in planes of development. These planes are approximately 6-year spans of growth. The groups of children share characteristics during these 6-year periods. Mixed age groups support the child’s development, which is why Montessori schools have mixed-aged classrooms. It was in 1938 or 1939 that Dr. Montessori called these age groups, planes. Each of the planes of development has its own set of characteristics. Within each plane, if the conditions are favorable, the child will grow. A favorable environment has loving, caring adults and a properly prepared environment. If conditions are not favorable the urge to develop is still present in the child. But their energy goes into deviations instead of self-construction. Deviations get in the way of development.
How Human Tendencies Are Expressed Differently
Dr. Montessori compared the stepping from one plane of development to the next to the metamorphosis of an insect. The insect is still the same but now has a different set of characteristics. This is the process for the human when passing through the planes of development. Throughout the lifespan of a child into maturity, the individual will be seen in four different ways. Each new plane is a rebirth, a change of personality. There are both psychological changes and physical changes that occur during these transitions. The human tendencies manifest differently at each plane of development.
Dr. Montessori observed this change of characteristics at each plane. The way that human tendencies are expressed is different across the different planes of development. An example of a human tendency being expressed differently across different planes is the human tendency for order. Young children, 3 to 6 years old, may have a hard time if the teacher moves around the entire environment, but for the second-plane child (6 to 12 years old) it is not a big deal. The second plane child will just want to know the reason for it to be able to understand why it was done. The child has the same tendency towards order, but the way that the order around them affects them changes throughout the planes of development.
Overview of the Planes
Each plane lasts roughly 6 years, but this varies from individual to individual. A successful completion of the previous planes is necessary for the child to flourish in the next plane. There are new characteristics at each new plane of development. These characteristics are present even if the prior plane wasn’t optimal and there was a weaker foundation. These are the age categories of the four planes of development.
Four Planes of Development
Each plane has two sub-phases; these sub-phases are very prevalent in the 1st and 3rd plane. The first half of each stage is a period of construction or building. Whereas the second sub-phase is a consolidation of what was constructed. Montessori environments group children by their age group as it corresponds to the planes of development. There will not be a class of 4-7-year-olds, this is mixed ages but from different planes, so the characteristics are different and so the needs need to be met differently.
Each plane has a parallel plane. The 1st and 3rd planes are planes of turbulent growth and rapid change, the time when there are lots of hormones present. It is in the 3rd plane of development, the adolescent years, that puberty takes place. Children and young adults in the 1st and 3rd plane are more susceptible to illness and there is less room for intellectual growth because the body is growing so much. The 2nd and 4th planes are the other set of parallel planes. During these two planes, crystallization occurs, the child and young adult typically have good health and there is lots of room for intellectual growth.
Detailed Look at the Psychological Characteristics of the Planes of Development
Each plane has distinct characteristics that will be the driving force behind its growth during the years of each plane. There are different needs for each plane of development and natural inclinations that we can be aware of to help guide young people during a particular time.
First Plane: 0-6 years old -Infancy
The Absorbent Mind
During the first plane, there is tremendous physical growth. The first plane child is guided by the absorbent mind. The child takes in everything, which lays the foundation for the intelligence. The child does not think analytically but is like a camera. Dr. Montessori describes the absorbent mind like a camera, it is non-discriminatory. It takes in impressions of one flower or a whole forest of trees with the same amount of ease. The child uses her senses to take in impressions of her world.
She has sensitive periods, which are when the senses are used to explore her environment. Her human tendency to communicate is expressed with language. She works to order, to move, and to perfect her senses by exploring the immediate environment around her. The young child needs to experience human language; it is needed often and early on because it is the child that creates her language. She needs opportunities for movement as well. The child desires to know, what and where. She will ask for the names of things many times. She needs concrete experiences as well as repetition. It is repetition, which will significantly improve her development.
Sub-Phases of the First Plane
The first plane is split into two sub-phases. From 0-3 years old is the unconscious mind. The second half of the first plane, from ages 3-6 is referred to as the conscious mind. This is when the child will be trying to answer the question “What is this?” The personality of the child develops throughout the first plane as well.
Second plane: 6-12 years old – Childhood
The second-plane child uses her reasoning mind and the power of her imagination to build herself. Physically we can see her baby teeth disappear. She wants to take risks and be the one to climb the highest or carry the heavy things. We see a lot of physical independence during this plane of development. There is great intellectual growth for the second-plane child. She seeks to understand why and how things work and function in the world around her. She starts great work and does it with maximum effort. A traditional education classroom structure may not support this need for great work. Yet a Montessori environment is prepared specifically with the child’s needs in mind. We are offering opportunities to develop new skills and build and develop social connections.
Her reasoning mind wants to know how and why things are the way that they are. Facts aren’t enough It is the reason behind the facts that she wants to know and understand. She has a powerful imagination and empathy for human beings she has not met. She is very concerned with fairness and justice and wants to know what is right and what is wrong. If a child comes and “tattle tails” on a child, we are to respond to them by saying what is right and wrong. They are looking for this kind of response because they are trying to order in their mind as to what is right and what is wrong. At this time in their development, they are developing their moral independence. Once they develop this for themselves, they will no longer come and ask, for it will have already been solidified for them.
A second-plane child can be rude because her energy is not in the place to be so kind. But she looks to other human beings to model behavior for her. If there is not a human figure to do this, she may look to fantasy characters to model behavior after. We want to be role models for these children. A characteristic of the second plane is hero worship. Meaning that they need those role models to emulate. These role models can be ways to inspire and encourage healthy formation of character during these childhood years.
There is a strong desire and need for relationships with peers. The child will work in groups and it is within these groups that the children will create a society amongst themselves. The exercises of practical life for her are going out into society and participating in society. A Montessori approach will support the child’s own particular need to be out in society and not just within the walls of the school setting.
Third Plane of Development: 12- 18 years old – Adolescence
The young adult of the third plane of development will go through so many changes. This is a time of rapid physical and emotional changes creating more emotions and sensitivities. The adolescent needs respect and to be treated as a young adult and not like children. They are becoming a socially conscious human being. Their friends and peers or of significance and importance to them. The time in the third plane of development is a time when the individual may be idealistic and searching for and discovering their intended vocation.
There are two sub-phases in the third plane. The 1st sub-phase is puberty. This is a time of rapid physical change that occurs and there are mood swings during this time. There is a diminished level of intellectual capacity because of the focus on physical development. The adolescent needs a different kind of work to satisfy her needs. She needs more creative work.
The 2nd sub-phase is adolescence. While there are still physical changes, what was constructed in the 1st phase crystallizes in the 2nd phase. Wisdom teeth will appear. Dr. Montessori developed an environment for the 3rd plane child. The word is Erdkinder, which means children of the earth. Dr. Montessori spoke of Erdkinder being the environment of the 3rd plane child. The child would live away from her family. Living either on a farm or in housing where the children would run a store. This work allowed her to be part of society.
Fourth Plane of Development: 18-24 years old – Maturity
Dr. Montessori left less information on the 4th plane of development. What was envisioned was a college-like system for the adult maturing. This would consist of learning philosophy and discussing the topics. The human from ages 18-24 is a full member of society and has moral responsibilities. Her skeletal growth is complete, but her brain is still developing and will continue past age 24.
Results of Normal Development
The result of normal development is joyous and mature adults. This is automatic if the passing through all of the other planes has been satisfactory. The developed adult will have a clear view of humanity and can be a contributing member of society.
Montessori’s Visual Representation of the Planes
There are two charts that Dr. Montessoir used to illustrate the planes of development. They may be helpful as you come to understand these four planes of development.
The Constructive Rhythm of Life- (Perugia 1950)
This illustration visually looks very regular. There are red triangles, which represent infancy and adolescence, these both are turbulent growth periods. There are blue triangles, which represent childhood and maturity. Each plane has subcategories, but the 1st and 3rd planes have a red line through the half-waypoint of the triangle, this represents the sub-phases of construction and then consolidation. There is a flame around “0”, this represents the energies of the child. The yellow illustration on the bottom represents what traditional schools and society give attention to, at which time in a human’s development. The arrows show the amount of attention given by society. There is one arrow in the first plane of development and as the child gets older, the more input society gives.
The Bulb- (Roma-1951)
This illustration is not symmetrical but is organic. There is a longer time shown in utero. The chart shows a steady development in both the 2nd and 4th planes. There is steep growth from 0-12 and then it levels off as the child continues to get older. The 1st and 3rd planes are represented as bulbs, colored in red. This represents the hot lava-like potential that is alive during that time. It is on fire. At the bottom of the chart, the names are of people who focus on that plane of development. The “X” is the potential of the human being; it is the great unknown, just like in an algebraic equation.