GAM 12 Identical Blue Triangles

The set contains twelve identical right-angled scalene triangles in blue, together with a wooden box and lid for storage. Because every triangle is the same, children can combine and rearrange them freely to build and compare a variety of larger figures.

In the elementary Montessori classroom the child joins the identical triangles along their matching sides to form new shapes. By overlaying and rebuilding figures, they find how different arrangements can cover the same area, turning abstract geometric ideas into something concrete and movable.

It is used to explore equivalency, congruency and similarity. Working with the twelve matching triangles, the child sees how shapes can be equal in area, identical in form, or proportionally alike, laying concrete groundwork for later geometry taught in the abstract.

Using one repeated right-angled scalene triangle lets the child focus on how the same unit combines into many figures. Identical pieces make relationships of equivalency and congruency visible, because any shapes built from the same number of triangles must share the same area.

The material belongs to the elementary Montessori classroom, where children are ready to reason about area, congruency and similarity rather than simply build. It suits learners who have moved beyond early sensorial shape work and are exploring geometry more analytically.

Yes. The twelve triangles come in a wooden box with a lid, which keeps the pieces together between lessons and makes it easy for a child to carry the work to a table and return it to the shelf. Keep the box dry and away from direct sun.