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4th Grade Math – Classifying Triangles

Clip 1/18: Pre-Lesson: Classifying Triangles Part 1

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Hillary Lewis and several mathematics educator colleagues gather together to review the lesson she will teach. Lewis describes her collaborative process of developing the lesson and the purpose of developing students’ conceptual vocabulary of classification and categorization.

Teacher Commentary

Hillary Lewis

I like to develop students’ skills, being able to think through that categorizing idea of trying to make sense of things. It’s a thinking skill, rather than waiting for somebody to tell you how it goes. The titles — isosceles, scalene, the name of it itself — I don't think are as important as understanding that those triangles have those kinds of differences in side length and angle measure.