Geometric Solids

The geometric solids give the child three-dimensional form as a sensorial object. The eye, hand, and mind build a bridge between plane figures and solid geometry. A solid matched to the wrong base or named incorrectly fails the felt shape.

• Framework: Montessori
• Unit: Sensorial
• Learning area: Visual Dimension
• Level: Ages 5-6

Objectives

• Recognize and name the geometric solids: sphere, cube, cylinder, cone, ellipsoid, ovoid, square-based pyramid, triangle-based pyramid, rectangular prism, triangular prism
• Identify solids in the environment
• Feel solids blindfolded to learn their shape from touch
• Prepare for geometry and mathematics

Materials

• Set of ten wooden geometric solids, painted in a uniform color (usually blue)
• Black felt mat
• Corresponding bases for each solid (squares, circles, triangles, rectangles, ellipses)
• Blindfold

Instructions

1. Present three solids at a time (sphere, cube, cylinder). 2. Hand the first solid to the child. 3. Feel it — smooth, round, rolls. 4. Say 'sphere.' 5. Repeat for cube and cylinder. 6. Use a three-period lesson to name the three. 7. Introduce the matching bases (circle, square). 8. Place each solid on its correct base. 9. Over many sessions, introduce all ten solids and blindfold work.

Educator tip

Let the child roll the sphere, stack the cubes, and explore freely before formal naming. The tactile exploration is half the lesson.

Assessment

Note naming accuracy, ability to identify solids in the environment, and matching to bases.

More from Sensorial

• The Decanomial — Layout of the Table of Pythagoras
• Cubing Material — The Power-of-3 Cube
• Trinomial Cube — Algebraic Extension
• Geometric Cabinet — Polygons Drawer
• Constructive Triangles — Blue Rectangular Box
• Tasting Bottles — Gustatory Discrimination
• Mystery Bag — Paired Stereognostic Refinement
• Botany Cabinet — Leaf Shapes