The child sorts the geometric solids by feeling their straight and curved sides, then matches each to its corresponding base shapes.

The Geometric Solids

Aim

The child can recognize the geometric solids that are found in the everyday environment.

Objectives

• Learn the names of the geometric solids
• Gain awareness of the geometric solids found in the everyday environment

3+

Materials

• A basket containing the geometric solids
• A box with the base shapes
• A small mat

Control of Error

Visual (when the child is not wearing a blindfold to perform the exercise)

Language

The names of the geometric solids: sphere, prism, pyramid, cube, cone, cylinder, etc.

Presentation

Place the basket containing the geometric solids on the table. Lay out the small mat as a contained space for this activity. Pick up a solid and slowly feel it. Pass it to the child and allow her plenty of time to explore it, feeling its roundness, angles and straight sides.

Once the child has fully experienced each geometric solid, you may offer the child three solids that differ in shape and introduce their names.

The most attractive way of teaching a child to recognise these forms is for him to touch them with closed eyes and to guess their names … After an exercise of this kind the child observes the forms when his eyes are open with a much more lively interest.
—Maria Montessori in Dr. Montessori’s Own Handbook

Show the child how to sort the solids, choosing one for each family, i.e., one curved solid, one plane solid, and one solid both plain and curved.

Ideas

Extend the child’s learning by offering her everyday objects, such as tea boxes or coffee tins, and ask her to match them to the geometric solids.

Provide the child with opportunities to create personal objects through junk modelling. This supports the child’s discovery of which shapes do and do not fit together.

You may also set out activities to help the child further discover the way that solids move, such as marble runs.

The sphere rolls in every direction; the cylinder rolls in one direction only; the cone rolls round itself; the prism and the pyramid, however, stand still, but the prism falls over more easily than the pyramid.
—Ibid

Further Challenges

You may show the child how to place the solids on their bases; the child will discover that various solids can share the same base.