# Montessori Constructive triangles Box 5 – experimental box

MATERIALS:

Box 5 is a triangular box  which contains 8 blue triangles:

·  2 small equilateral triangles.

·  1 small obtuse angle scalene triangle.

·  2 large right angle isosceles triangles.

·  1 small right angle scalene triangle.

·  2 medium right angle scalene triangles.

OBJECTIVES:

To give the child the opportunity to experiment with various geometric shapes.

To show that all plane, flat, rectilinear figures are composed of triangles.

To indirectly prepare the child for later work in Maths and Geometry.

AGE:

4 – 4 ½ years approx.

PRESENTATION:

Individual exercise done at a table or on a floor mat. Select a triangle and show the child how to find the match by placing the triangles on top of its match. Holding one triangle with the left hand, slide the other triangle around it with the right hand. Make a shape and leave it for a while so that the child can see it. Slide the triangles back to its original shape.

There are no black lines on the triangles to guide the child.

This is the only box with no “control of error” – it is solely for experimental purposes.

Also, sliding the triangles to find its match is only permitted in this exercise.

PRESENTATION 2:

Give a three period lesson on the names of the shapes.