Montessori Trinomial Cube Lesson Details + DIY alternative

Table of Contents

What is the Montessori Trinomial Cube?
Presentation
Extension Activities

What is the Montessori Trinomial Cube?

The Montessori trinomial cube is composed of 27 wooden blocks designed to fit within the box and form a bigger cube. This also introduces essential algebraic concepts and provides a tangible representation of the (a + b + c)^3 formula, thus preparing them for more advanced mathematical understanding.

Construction of the trinomial cube follows this formula:
(a + b + c)^3 = a^3 + 3(a^2)b + 3(a^2)c +3ab^2 + 6abc + 3ac^2 +b^3 + 3b^2c + 3bc^2 + c^3

Material

– 1 red cube (a^3)
– 1 blue cube (b^3)
– 1 yellow cube (c^3)
– 3 red and black prisms (a^2 b)
– 3 red and black prisms (a^2 c)
– 3 blue and black prisms (ab^2)
– 3 yellow and black prisms (ac^2)
– 3 blue and black prisms (b^2 c)
– 3 yellow and black prisms (bc^2)
– 6 black prisms (abc)

You can use printable DIY alternative HERE.

Prerequisite

– Binomial Cube

Control of Error

– Everything fits with even planes around the cube
– Mechanical: When put inside the box, the doors will close and the top lid fits
– Perceptual: Top prisms match the pattern on the lid

Direct Aims

This allows the child to build the trinomial cube.

Indirect Aims

It also prepares the child for algebra and for finding a cube root.

GET the DIY Alternative here

Presentation

Watch these videos (building by color & building by layer) to learn how to present this lesson.

Show the child how to remove and rebuild the binomial cube.
Use visual discrimination to choose and place a^3 in the corner.
Look at and point to the red side. Locate and place the red and black prisms (a^2 b) on each side of the red cube.
Build the rest of the layer from the inside out.
Build the second and third layers from the inside out as well.
Close the box and invite the child to repeat.

Extension Activities

Building outside the box and showing the patterns on the sides and top horizontally and vertically
Building one layer next to each other
Building stereognostically