A Subtle Art: The Beauty of the Montessori Three-Period Lesson
Rebecca Lingo • April 1, 2024

At Wheaton Montessori School and in Montessori education all over the world, we have a subtle art for connecting children to new concepts, a technique we call the Three-Period Lesson. This structured approach is designed to introduce and reinforce new concepts in a way that works with children’s natural learning tendencies. It consists of three distinct phases, each serving a crucial purpose in the learning process. 


The First Period: Naming


At Wheaton Montessori School, we focus on helping children create an association of the item or sensorial perception with its name in this part of the lesson. This is a statement of vocabulary, but its simplicity should not disguise the great importance of this period. Proper execution is vital to success and as such our teachers execute this part of the lesson with extreme exactitude. We take great care to avoid any peripheral information which would serve only to confuse. The emphasis here is on clear articulation and repetition, allowing children to absorb the information through auditory and visual cues.


If the lesson is focused on sensorial perception, we first help a child awaken that sense before giving any vocabulary. For example, if we are introducing a very young child to the vocabulary for temperature, we use a set of thermic bottles. We first isolate the hottest and coldest of the bottles. We feel the “hot” bottle, invite the child to feel it, and state: “This is hot.” Then we have the same procedure with the cold bottle, first feeling, then stating: “This is cold.” If necessary, we may repeat the experience, associating the bottle with its attribute: “Hot…. Cold.” We take great care in pronouncing the vocabulary or attributes clearly and distinctly so that children can easily absorb the vocabulary. We also make sure to avoid any additional descriptions or explanations.


The purpose of the first period is to help children connect the sensory data stored in the right hemisphere of the brain with its precise language, stored in the left hemisphere of the brain. This neural connection fixes the perception in children’s minds and provides an index to the sensorial impression, making it accessible to the conscious mind.


The Second Period: Association


In this phase, we focus on having children recognize the object in correspondence to the language. It is a way for us to see if a child has been successful in the association of the perception with its name as presented in the first period. In the second period, we use the vocabulary in a series of lively and fun declarative commands that encourage repetition. 


For example, if presenting large and small with a cylinder block, we might ask: “Which one is large?” “Which one is small?” “Put the large one here.” “Put the small one here.” “Show me the large one.” “Point to the small one.” This activity has a game-like feel and offers children the chance to repeatedly hear the vocabulary and associate it with the corresponding attribute or object. 


During this period, we do not ask children to recall the vocabulary. Because there is active participation that reinforces the association between the name and the object or concept, this period is about reinforcement. It is the longest of the three periods and is the most important one in terms of serving as an aid to children’s memory. Every time a child hears the vocabulary and associates it with the corresponding attribute/object, it activates the necessary synaptic connections in the brain and strengthens neural pathways. 


If a child is not successful in the second stage, we have two choices: return to the first period or gracefully end the lesson and offer it again another day. It might be that a child just needs more time to work with the materials sensorially. Regardless, if the child isn’t experiencing success at this stage, we recognize that we need to 

reassociate the sensory impression with the name. We don’t point out the error to a child, though, because that only serves to embarrass the child or cause them to feel defeated. Nor is it helpful to continue with the lesson, for if the associations are not happening, more repetition would only serve to cause further confusion.


The Third Period: Recall


This last part of the lesson is just a quick test and serves as a verification that a child has successfully retained the association given in the first period. For the first time, we no longer provide the vocabulary, and instead, the child must produce it from their memory. We simply ask: “What is this?” If the child can successfully answer a series of times, then we can verify that the association has been created. If the child is not successful, we repeat the first or second period. This is not done as a means of correction, but to ensure the child leaves the material with an accurate impression. 


Once the Three Period Lesson is over, we allow children to continue working with the material. Often, we see that they have renewed enthusiasm for the material after making these new mental associations.


A Powerful Approach


By following this structured approach at Wheaton Montessori School, we provide children with multiple opportunities to engage with new information and reinforce their learning through repetition and active participation. This approach is powerful and effective for three main reasons: 


Respect for the Child's Learning Pace

The three-period lesson respects the individual pace of each child's learning journey. By breaking down new concepts into manageable steps, we cater to the diverse needs, abilities, and learning speed of each child.


Promotion of Active Engagement

Through interactive questioning and hands-on activities, the Three-Period Lesson encourages active engagement and participation. Children are not passive recipients of information but rather active participants in their learning process, leading to deeper understanding and retention.


Facilitation of Meaningful Connections

By associating new concepts with real-life objects or experiences, the Three-Period Lesson helps children make meaningful connections between abstract ideas and concrete examples. This approach fosters holistic understanding and lays the groundwork for future learning.



Above all, the beauty of the Three-Period Lesson lies in its simplicity and effectiveness. The technique is subtle yet consistent, the lessons are brief yet powerful, and the language is precise yet expansive. Ultimately, the Three-Period Lesson empowers children to become active learners, capable of exploring the world with curiosity and confidence. 


We invite you to come see this technique in action. Current families can schedule a classroom observation by using the green buttons below. 


Adolescent Seminar Observation Ms. Searcy’s Upper Elementary Classroom Observation Mrs. Fortun’s Lower Elementary Classroom Observation Mrs. Mayhugh’s Lower Elementary Classroom Observation Mrs. Berdick’s Primary Classroom Observation Ms. Carr’s Primary Classroom Observation Ms. Chiste’s Primary Classroom Observation Mrs. Rogers’s Primary Classroom Observation

We are enrolling children who will be between 2.5 and 4 for summer and fall 2024 start dates. Prospective families are invited to schedule a school tour by clicking on this link or the green Schedule a Tour button on the upper right-hand corner of this page.  


How Geometry Got Its Name
By Rebecca Lingo February 2, 2026
In Wheaton Montessori School classrooms, we like to introduce big ideas with big stories. We offer children a sense of wonder first, sort of like an imaginative doorway, so that when they later study formulas, theorems, and proofs, they already feel connected to the human story behind them. One of these stories is The Story of How Geometry Got Its Name, an introduction to a subject that is far older than the textbooks and protractors we encounter today. In Montessori, Geometry is more than about shapes. It is about human beings solving real problems in the real world. A Problem as Old as Civilization To reintroduce geometry, we time-travel back around 5,000 years to the ancient civilization of Egypt. This was a land shaped by the Nile River, the longest river in the world. Each year, the Nile flooded its banks as snowmelt poured down from the mountains far to the south. The Egyptians depended on this yearly flood as it left behind rich, dark silt that nourished their crops and made life possible in an otherwise harsh desert. But the flood created a challenge, too. It washed away the boundary markers that separated one farmer’s field from another. When the waters receded, no one could quite remember where their land began and ended. Arguments ensued. “This corner is mine!” And the fields needed to be measured and marked again. The First Geometers: The Rope Stretchers To solve this annual problem, the Egyptians relied on a special group of skilled workers called the Harpedonaptai, or Rope Stretchers. These were early land surveyors who used a knotted rope tied at regular intervals and three weights to create a very particular triangle. In our elementary classrooms, we invite a few children to hold a prepared rope at its large knots, forming that same triangle. As they stretch it out and lay it on the ground, many quickly recognize what the Egyptians had unknowingly created: a scalene right-angled triangle. This shape would later become central to the geometry studied by Greek mathematicians. The Harpedonaptai used this simple tool to re-establish field boundaries, set right angles, and make sure the land was measured accurately and fairly. Geometry, in its earliest form, served a deeply practical purpose. From Rope to Pyramid The Harpedonaptai’s expertise was valued far beyond the farmlands. They also helped lay out the foundations of temples, monuments, and even the Great Pyramid of Giza. The base of the Great Pyramid is a perfect square, which is an astonishing feat of measurement and design. The Pharaoh himself oversaw these measurements, but it was the Rope Stretchers who executed them. Their work represents one of humanity’s earliest recorded sciences: the careful measuring of the earth. How Geometry Got Its Name The name geometry reflects this ancient practice. It comes from two Greek words: gê — earth metron — measure Geometry literally means earth measurement. The Egyptians did not use the language of right angles, nor did they classify triangles as we do today. Their work was grounded in practical needs. They needed to solve problems, organize land, and create structures that would endure for thousands of years. Yet their discoveries influenced later thinkers like Pythagoras, who likely traveled to Egypt and learned from their methods. Over time, the simple knotted rope inspired a whole discipline devoted to understanding lines, angles, shapes, and the relationships between them. Why We Tell This Story in Montessori When Montessori children hear this story, something important happens. Geometry becomes more than a set of rules or vocabulary words. It becomes a human endeavor born from curiosity, necessity, and ingenuity. The heart of Montessori education at Wheaton Montessori School is to help children view knowledge not as isolated subjects, but as valuable gifts passed down from earlier generations. When children pick up a ruler, explore angles with a protractor, or classify triangles in the classroom, they are continuing a legacy that began with those early Rope Stretchers, the Harpedonaptai on the banks of the Nile. Through story, students feel connected to the people who shaped our world and to the problems that inspired great ideas. Geometry becomes meaningful, purposeful, and alive, from our preschoolers working with the Geometry Cabinet , to elementary students classifying and measuring angles or using hands-on Pythagorean Theory materials, and all the way through our adolescents. At the adolescent level, geometry moves fully into the real world. Students apply measurement, angles, area, scale, and spatial reasoning through meaningful work across campus, including: Measuring and mapping land for the campus’s Wetland Conservation Area, as well as calculating classroom square footage for recognition and accreditation applications Understanding and applying area, perimeter, scale, and proportion when working with acreage, restoration plans, and campus layouts Designing and situating functional structures such as chicken coops using geometric principles Applying angle classification, measurement, and spatial reasoning through woodworking Using geometry to cut, join, and build accurately, including raised beds, greenhouses, and beehive insulation boxes
Child reaching for an object,
By Rebecca Lingo January 26, 2026
Learn how the Montessori Absorbent Mind empowers young children to effortlessly absorb language, culture, and behavior, and how parents can nurture it.