# Geometric Solids

GEOMETRIC SOLIDS

Language

Loud and Soft
The positives, comparatives, and superlatives.

Purpose

Direct
To refine the stereognostic sense.
To make the child aware of the solid shapes that surrounds him.

Indirect
Preparation for geometry.

Control of Error
Visual

Age
3 1/2 years onwards

Materials
– A basket large enough to contain ten geometric wooden solids in blue:
A triangular prism
A rectangular prism
A cube
A cylinder
A cone
A triangular pyramid
A square pyramid
A sphere
An ellipsoid
An ovoid
– Seven white cards with geometric figures drawn in a thin blue line
– A suitable cloth (not transparent) large enough to cover the basket
– A mat

Presentation

Introduction
Invite the child to come and work with you. Tell the child that for today’s work, we are going to need a mat. Have the child unroll a mat. Bring him over to the shelf and show him the basket, giving the child the name of the material. Have him bring over the entire basket, placing it in the top right corner of the mat. Have the child sit your left.

Procedure 1
– Take out one of the simpler shapes (such as the sphere), and place it on the mat in front of you.
– Feel the solid in your hands by gently sliding you hands around the sphere.
– Allow the child to feel the sphere in the same gentle manner.
– Have the child place the sphere near the top left corner of the mat.
– Demonstrate on another solid, showing him again how to gently slide your hands around the solid.
– Allow the child to explore the other solids in the basket.

Procedure 2
(Prepare for the lesson in the same way as above.)
– Take out the sphere from the basket.
– Feel the sphere in your hands as in Presentation 1.
– Allow the child to feel the sphere and as he is doing so say, “That is a sphere”.
– Ask the child, “Can you put the sphere on the mat?”
– The child should then place the sphere on the mat.
– Take out the cube and repeat in the same way as with the sphere.
– Take out the cylinder and repeat in the same way as above.

– Then do a three-period lesson for: sphere, cube, and cylinder.
– On another occasion, repeat this presentation for three more solids until the child knows that names of all of the solids.

Exercises

Exercise 1
The child works individually with the geometric solids.

Exercise 2
The child chooses 3 – 4 solids. Place these in a separate basket and cover it with a scarf. Reach your hand under the scarf, feel one of the solids underneath, and say out loud what solid you believe you have in your hands. Take out the solid from under the scarf to reveal the solid you have. Allow the child to do as you have shown. This allows the names of the solids to be reinforced for the child. Work in this manner until the child can place a scarf over all of the solids and still feel and guess correctly.

Exercise 3
Take out three cards of contrast. Place the cards on the mat and see what solids fit onto each card. Allow the child to experiment with all of the cards.

Exercise 4
In a tray of sand, gently roll one shape at a time to see what forms it can make.