Stages of Development Series: Maturity
March 24, 2025

This is the final post of a series focusing on each of the four stages (or planes) of development: birth through age six, ages six to twelve, ages twelve to eighteen, and ages eighteen to twenty-four. Montessori pedagogy calls for a big picture perspective that incorporates the fundamental principles of human development at each stage of development and how we can best provide for a developing young person in each stage.


A Path Toward Maturity and Contribution to Society


The journey of human development, as envisioned by Dr. Maria Montessori, is marked by four distinct planes. Each plane represents a different phase in an individual's growth, and the fourth plane, spanning from 18 to 24 years of age, is no exception. This phase, which Montessori refers to as Maturity, signals the culmination of psychological and physical growth and paves the way for young adults to step into the world as a fully formed individuals capable of significant contributions to society.


Characteristics of the Fourth Plane


The fourth plane represents a time when individuals reach the height of their development and begin to assume their role in society. Unlike the earlier planes, the psychological changes during this period are less dramatic and more internal, and the focus shifts to understanding oneself and the world beyond one’s immediate needs. Whereas the body completes its physical maturation, the mind embarks on the task of understanding how it can contribute to humanity.


In The Four Planes of Education, Dr. Montessori writes, “The individual should be the man who knows how to make his own choice of action having passed to perfection the preceding phases. He should be as a live spark and aware of the open gate to the potentialities of prospective human life and of his own possibilities and responsibilities” (p. 15). This encapsulates the essence of the fourth plane— young adults’ newfound ability to make independent choices while being aware of their potential impact on society.


In this stage, individuals are not merely focused on themselves but are also learning to engage with the world beyond their personal ego. The question that arises is not “Who am I?” but “What can I do?” This shift from self-centeredness to a broader, more collective view of life signifies the maturity that defines the fourth plane.


Conquest of Independence


One of the key aspects of the fourth plane is the conquest of independence, particularly economic independence. This phase marks a time when individuals strive to become self-sufficient within the larger society. Young adults move beyond the dependency of childhood and adolescence, assuming more responsibility for their own life, finances, and future.


This is a period when a personal mission begins to take shape. Young adults start to solidify their goals, whether academic, professional, or personal, and work toward them with a growing sense of purpose. Dr. Montessori believed that achieving economic independence was crucial, as it not only provides the means to live but also fosters a sense of autonomy and responsibility.


Observable Examples of Development


Physically, by the fourth plane, development is largely complete. The dramatic growth spurts of the previous stages have slowed, and young adults now have full mastery over their body. Health is typically stable, and there is an overall sense of well-being.


Much like the second plane, the fourth plane is also conducive to intellectual pursuits, particularly those that lead to specialization in areas essential for a future career. This is when our young adults are honing skills that will serve them in the professional world, whether through higher education, apprenticeships, or other forms of specialized learning.


The fourth plane is also a time when individuals, having developed a solid understanding of themselves, are ready to take on more significant intellectual and social responsibilities. This is when they truly start asking the big questions, such as, “How can I contribute to the world?” It is at this stage that young adults embark on the exploration of their "cosmic task," a concept Montessori introduced in the second plane, which refers to the idea that every individual has a unique role to play in the larger story of humanity.


The Role of the Supportive Environment


With significant internal growth happening during the fourth plane, the role of the external environment remains crucial. A supportive environment during the preceding planes can have a profound effect on how individuals move through this stage. If our young adults have been nurtured in an environment that promotes autonomy, responsibility, and respect for their capacity to make choices, they are more likely to enter adulthood with the skills and mindset necessary to thrive in society.


To prepare for their careers during this time, many young adults pursue higher education, either through university studies or vocational training. Alternatively, they may enter the workforce, beginning to take on professional roles that contribute to society. This is also a time when many young adults leave the family home and start families of their own, further solidifying their place in the world as independent adults.


Dr. Montessori, unfortunately, did not have the opportunity to explore this phase in depth. However, we can imagine a world where every individual has been given the best possible environment throughout the previous planes of development. In such a world, adults who emerge from the fourth plane are equipped not only with the knowledge and skills to succeed but also with a profound sense of responsibility toward the greater good.


An Enlightened Society


The ideal outcome of the fourth plane is individuals who not only seek personal success but also work toward the welfare of humankind. Young adults who have passed through the earlier planes of development with the support of nurturing environments can enter society with a strong social conscience, eager to contribute to the collective well-being of humanity. They see the interconnectedness of all people and seek ways to address societal issues and contribute to the common good.


Imagine a world in which all young adults, having been guided through the previous developmental stages, emerge from the fourth plane ready to play their roles in society—not only as self-sufficient individuals but as enlightened members of a larger human community. This vision encapsulates the Montessori ideal: a world where everyone has the potential to contribute meaningfully to the advancement of humanity as a whole.


The fourth plane of development is not merely a time for self-discovery but a time for self-realization and societal contribution. Young adults, secure in their independence, prepare to engage with the world in ways that transcend personal goals, focusing instead on broader responsibilities. By fostering an environment that nurtures growth and independence, we set the stage for a society composed of individuals capable of making meaningful contributions to humanity’s collective well-being.


Curious to see how attention to the characteristics and needs of earlier stages of development can support an enlightened society? Schedule a tour today! 



Montessori Materials Explained: The Fundamental Needs Charts
May 26, 2025
Through Fundamental Needs Charts, Montessori students discover how all people meet life’s essential needs, nurturing empathy and understanding.
Practical Life Has Purpose!
May 19, 2025
The Purposes of Practical Life in Montessori In a Montessori classroom, practical life activities play a foundational role in supporting children’s development, independence, and connection to their environment. Because children are actively absorbing and adapting to the world around them, everything we offer in practical life serves a developmental need. Supporting Independence One of the primary goals of practical life is to nurture children’s functional independence—the ability to care for oneself and the environment and interact meaningfully within a community. The first plane of development (0 to 6 years) is marked by a strong drive for independence, with children eager to do things for themselves. By the time a child enters the Children’s House (approximately ages 2.5 to 6), they have already made strides toward independence. However, they still require an environment that allows them to refine their skills. In the world, children generally encounter a number of obstacles to their independence: Household processes (e.g., cleaning dishes in the dishwasher) may be hidden or too complex. Tools are adult-sized and difficult for small hands to use. Movements happen too quickly for children to absorb (e.g., tying a shoe). The Montessori environment addresses these barriers by providing: Child-sized tools for daily activities, such as preparing food and caring for the classroom. A clear, ordered sequence of movements that children can observe and repeat. The freedom to practice skills at their own pace, allowing them to move from passive observers to active participants. Supporting the Sensitive Period for Movement We also recognize that young children are in a critical period for refining their control and coordination. So practical life activities are designed to help children refine their movements in purposeful ways, directing children’s attention and energy toward focused, intentional actions. Walking on the line of an ellipse develops balance and control. Pouring water from a basin to a bucket refines precision. Carrying a tray teaches careful, measured movements. One of the most challenging yet essential aspects of movement is control. It takes effort to stop pouring just before a cup overflows or use only a small drop of polish when shining an object. By engaging in these exercises, children strengthen their willpower and gradually master their own actions. Supporting the Sensitive Period for Order Children in the first plane of development have an innate need for external order, which is reflected in their surroundings and daily routines. Montessori environments support this in a variety of ways. We ensure that activities have a logical sequence of steps so as children learn new concepts, they can also rely on the sequencing. Materials are placed in a specific order on the shelves, moving left to right and top to bottom so children begin to internalize the same patterning we use for reading as they work through the easier and most concrete activities to the most challenging and abstract. Montessori activities are color-coded. For the youngest children this means that all of the items for something like window washing will have the same color which helps children keep the set together. As children get older the color-coding is designed to help them grasp concepts like place value in math or parts of speech in language. Once children internalize these structures, they gain confidence and independence, allowing them to complete tasks from start to finish without adult intervention. Assisting with Cultural Adaptation Practical life activities reflect real-world tasks that children observe in their daily lives. Children are naturally drawn to meaningful work—they want to help, imitate, and participate. For example, in Dr. Montessori’s early observations in San Lorenzo, she saw that children were fascinated by the gardener and the custodian, eagerly following and watching their work. Children see adults doing marvelous activities, and children want to learn the skills to participate! Through practical life activities, children engage in culturally relevant tasks that allow them to feel like valuable members of their community. Supporting Orientation Orientation is a fundamental human tendency—we all seek to understand our surroundings and how to function within them. Practical life exercises help children orient to the Montessori classroom by introducing essential routines. For example, we take the time to teach children things that might otherwise be taken for granted, such as: How to carry a chair properly. How to greet a friend. How to roll and unroll a work rug. How to ask for help. By taking time to demonstrate these tasks, we show respect for the child and provide the knowledge they need to act confidently in their space. Supporting the Development of Concentration Practical life activities serve as a gateway to deep concentration. The freedom to choose and repeat exercises allows children to follow their intrinsic motivation and work toward self-perfection. When children reach deep concentration, they experience: Joy and a sense of fulfillment. An increased connection to others. A natural reduction in undesirable behaviors. The ability to repeat an activity for as long as needed also supports children’s sensitive period for order and mastery. This is why practical life often serves as the first point of engagement for children in the Montessori classroom. Supporting the Development of the Will Practical life exercises help children develop willpower and self-control by bridging the gap between impulse and deliberate action. At first, children act on instinct, but through repeated exercises, they learn to: Act consciously and voluntarily. Perfect their actions through self-correction. Develop grace, courtesy, and social awareness. Whether through learning how to clean up a spill or preparing snack to share with others, children learn to control their impulses and consider the needs of others. Dr. Montessori beautifully summarized this transformation in The Discovery of the Child: “The grace and dignity of their behavior and the ease of their movements are the corollaries to what they have gained through their own patient and laborious efforts. In a word, they are ‘self-controlled,’ and to the extent that they are thus controlled, they are free from the control of others.” Practical life is far more than just pouring, scrubbing, and folding—it is the foundation for independence, concentration, order, and social development. These carefully designed activities help children orient to their world, refine their movements, and develop the willpower to act with purpose. By embracing practical life, we give children the tools to engage meaningfully with their environment, take ownership of their learning, and ultimately, become confident, self-sufficient individuals. Contact us to schedule a tour so you can see how young children use practical life activities in powerful ways!