Materials Highlight: Geometry From the Start

July 25, 2022

When many of us think of our geometry education, we have thoughts of identifying shapes in kindergarten, and then taking a class or two in high school.

 

The truth is, children are fully capable, and enthusiastically prepared, to learn so much more at a much younger age. While we can’t possibly cover our entire curriculum in one short article, we’ll share some of the highlights. It begins (perhaps unsurprisingly) in our primary classrooms.

 

Geometric Solids

Pictured above, the geometric solids are our students’ first direct exposure to geometry. The solids are displayed on a shelf and are contained by a basket or tray. The adult invites the child to a lesson and asks them to retrieve the shapes. They then look at each one. The lesson may go something like this:

1.   The guide picks up the cube, feels each side, and hands it to the child. The guide states, “This is a cube.” The cube is placed on the work rug.

2.   The process is repeated for each solid in the basket.

3.   Depending upon the child’s readiness, they may continue, with the guide asking questions like, “Where is the cylinder?”

4.   After the child has had some time to interact with the material independently for a while, the guide will again sit with them and assess their understanding. This is done by holding one sold at a time and asking the child to name it.   

 

There are many fun extensions associated with this material. One favorite includes putting the solids on a mystery bag or using a blindfold so the child has to guess and identify by touch alone.

 

Geometry Cabinet

The geometry cabinet is used in primary and lower elementary classrooms, although differently in each. What begins as a lesson in identifying basic shapes and discerning between their sizes evolves into complex identification and blending of skills. Some of the skills this material helps us teach our students aged 6-9 include:

  • Types of triangles (acute scalene, acute isosceles, right scalene, right isosceles, obtuse scalene, and obtuse isosceles)
  • Quadrilaterals (trapezoids, a rhombus, and a parallelogram)
  • Regular polygons (pentagon, hexagon, heptagon, octagon, nonagon, and decagon)
  • Curved figures (curvilinear triangle, oval, ellipse, quatrefoil)
  • Rectangles
  • Circles

 

Constructive Triangles

Beginning during the primary years and continuing through lower elementary, the constructive triangle boxes are another child favorite. A series of boxes teaches a variety of concepts.

1.   Triangle box: Used to show how different types of triangles can be combined to make other triangles, also indirectly teaches fractions concepts

2.   Large hexagon box: Used to show how triangles can be combined to create other figures, including a hexagon, rhombus, and parallelogram

3.   Small hexagon box: A continuation of the same basic concept as the previous box, but this time triangles are used to create rhombi, a trapezoid, and another configuration of a hexagon

4.   Rectangle box: Triangles are used to create a square, rectangle, and other quadrilaterals

5.   Blue triangles boxes: While the previous boxes utilized different colors for different types of triangles, they are all painted blue here. This is basically an extension of previous work and allows children an opportunity to rely less on previously helpful visual clues. There is also lots of opportunity to use the blue triangles to create more complex geometric figures.

 

Classified Nomenclature

Once some of the more basic skills have been mastered by the child, sometime during early lower elementary, they move on to engage with the classified nomenclature. As with all other Montessori work, this is a step toward abstraction; they are no longer relying heavily on the wooden materials they can hold and manipulate, rather they are using drawings, booklets, charts, and labels.

 

This work can become rather in-depth and continues into upper elementary. A very broad overview of skills includes:

  • Fundamental concepts (point, line, surface, solid)
  • The study of lines
  • The study of angles
  • Plane figures
  • Study of the triangle
  • Study of quadrilaterals
  • Study of regular polygons
  • Study of the circle

 

These studies are not short lessons like the child has experienced previously. They are multi-layered and can take months to complete. For example, the study of angles may begin during the second year of lower elementary, but continue periodically through the years until the child reaches sixth grade. Concepts include:

  • Parts of an angle
  • Types of angles
  • The measurement of angles
  • Constructing angles
  • Relationships between two angles
  • Two lines and a transversal
  • Constructing and copying an angle
  • Bisecting an angle
  • Operations with angles

 

Beyond all these amazing materials, it’s important to note that there is a lot of crossover when it comes to Montessori subjects. One perfect example is a favorite grammar work of third graders called the Detective Triangle Game. While its main intention is to practice using correct adjectives, this is done by way of sorting a multitude of triangles, with different colors, types, and angles.

 

Want to learn more? Please reach out if you have any specific questions and want to have a conversation. As always, we believe the best way to truly understand what goes on in a Montessori classroom is to sit quietly and observe in one. Contact us today to schedule a tour.

October 26, 2026
When Dr. Maria Montessori began developing her curriculum for elementary-aged children, she recognized that their educational needs undergo a profound transformation. Academic skills become more complex, but more importantly, the way content is delivered must fundamentally shift. In the elementary years (ages 6–12), children transition away from the sensory, hands-on physical boundaries of early childhood and move toward an expanding intellectual horizon. Around age six, a child’s scope of vision expands exponentially beyond themselves. Social connections become paramount, a vivid imagination awakens, and a deep curiosity takes hold regarding the universe, society, and their own place within the big picture. To meet this developmental leap, Dr. Montessori created Cosmic Education—a holistic framework that presents the story of the universe and humanity’s interconnected role within it. The Five Great Lessons: Springboards for Imagination At the heart of Cosmic Education are the Five Great Lessons. These are not intended to be exhaustive academic lectures; rather, they are dramatic, impressionistic stories designed to ignite the child's imagination and serve as a springboard for all future research and learning. Because children spend three years in each elementary community (Lower Elementary: ages 6–9; Upper Elementary: ages 9–12), they experience these lessons three distinct times. Each year, as their cognitive capacity grows, the lessons reveal deeper layers of meaning, sparking fresh, student-led exploration in chemistry, history, mathematics, language, and the sciences. Great Lesson 1: The Creation of the Universe Typically presented at the start of the school year, this lesson offers a captivating sense of wonder. Guides intentionally prepare the atmosphere: drawing the blinds, dimming the lights, and gathering children around a series of impressionistic materials and science experiments. The story begins in the vast, cold darkness before the universe existed, building up to the instantaneous moment of creation. Through striking demonstrations, children observe: How particles moved together and apart The speed of light and the immense scale of stars States of matter (solids, liquids, gases) The formation of the solar system, the cooling of the Earth, and volcanic activity Follow-Up Studies: This lesson serves as the gateway to physics, chemistry, astronomy, geology, physical geography, and the scientific method. Great Lesson 2: The Coming of Life As the school year progresses, attention shifts to how life emerged on Earth. To help elementary students grasp deep time, guides utilize impressionistic visual materials: The Long Black Strip: A long runner of black fabric representing Earth's vast lifespan, ending with a tiny sliver of white to represent all of human history. This material provides a humbling visual perspective on our planet's timeline. The Clock of Eras & The Timeline of Life: Colorfully illustrated charts detailing life’s evolution from single-celled organisms through early plants, invertebrates, vertebrates, and dinosaurs. Follow-Up Studies: Children dive into biology, Botany, Zoology, the five kingdoms of life, vertebrate classification, and paleontology through fossil studies. Great Lesson 3: The Coming of Humans This lesson introduces early human ancestors and the arrival of human consciousness. Children reflect on what makes human beings unique—our ability to think, reason, feel deeply, and collaborate to invent tools that solve complex problems. Guides introduce the Fundamental Needs of Humans, demonstrating how all people throughout history and across cultures share the exact same core requirements for survival and fulfillment (shelter, nourishment, clothing, defense, spiritual expression, and art). Follow-Up Studies: Ancient history, cultural anthropology, world geography, social studies, and human migration patterns. Great Lesson 4: The History of Mathematics Elementary students are fascinated to discover that mathematics was not created out of thin air, but was invented by ancient civilizations to solve real-world problems, like measuring land, trading goods, and tracking time. By learning about the contributions of the Babylonians, Egyptians, Greeks, Mayans, and early Indian mathematicians who developed the concept of zero, children realize that numbers are a shared human heritage. Follow-Up Studies: When children work through subtraction, long division, or geometry, they ground their practice in historical context, making abstract math deeply meaningful and engaging. Great Lesson 5: The History of Language Similar to the history of math, this lesson illuminates how written language evolved. From early cave paintings and Egyptian hieroglyphics to the Phoenician alphabet and the printing press, students learn how humans captured spoken thoughts to communicate across distance and time. Follow-Up Studies: Because elementary students are actively refining their reading, grammar, creative writing, and research skills, understanding the origin of words (etymology) inspires pride and curiosity in their literacy work. Experiencing Cosmic Education at MSL Cosmic Education gives children a sense of purpose and belonging. Instead of delivering isolated facts, Montessori presents the whole universe first, allowing students to see how every detailed subject connects back to the grand story of life. Would you like to observe our Lower and Upper Elementary classrooms in action and see Cosmic Education at work? Schedule a tour today!
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