Constructive Triangles - Blue Triangles Box

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Constructive Triangles -
Blue Triangles Box
Sensorial - Visual Discrimination of Form
Age4 +
PrerequisitesConstructive Triangles - Triangular Box
Constructive Triangles - Rectangular Box
MaterialsBlue Triangles Box (a box containing 12 right scalene triangles)

Use of this material makes the child aware that all polygons can be made with triangles. This activity prepares the child for geometry.


  1. Take the material to a large mat. Lay out the triangles on the mat.
  2. Show that the triangles can be combined into other shapes in multiple ways.

Points of Interest

Control of Error

Variations and Extensions


Make Your Own

Printable version available to buy here:

Where to Buy

Prices and links last checked: 1 June 2020

Blue Triangles Box
Adena $18.69
Alison's $38.25
Bruin's $45.00
E & O $24.00
Hello Wood $53.00
Kid Advance $18.99
Leader Joy $20.95
Materials Company of Boston $31.00
Montessori N' Such $15.01
Montessori Outlet $18.95
Nienhuis $59.60
Thinkamajigs $15.26

Further Reading