Illuminations: Three Sides

In this lesson, students compare and contrast shapes using attribute blocks.

Because the equilateral triangle (a triangle with congruent sides and congruent angles) is the most common example used in textbooks and other reference materials, this is an important opportunity for you to help students realize that other triangles exist and that triangles can have angles of different measures. The lesson is designed to accommodate multiple learning styles and intelligences.


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Early Childhood, K-6, Educator

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Illuminations (National Council of Teachers of Mathematics)

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