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4th Grade Math – Classifying Triangles

Clip 18/18: Debrief: Classifying Triangles Part 6

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David Foster, mathematics education leader and mentor, describes the outcomes of the re-engagement part of the lesson. He identifies and discusses the basic ideas, having the students revisit the ideas, and then providing a ramp or additional cognitive demand to push the students’ thinking deeper and further. 

David cautions the educators to be precise in their own thinking, especially in labeling their instructional materials—for example, not using the term acute, but acute triangle.

Teacher Commentary

Hillary Lewis

Ultimately, what I find so interesting when you get to the end, it's like, “Wow, from where we thought we were headed, that's not what I was expecting." Working with other teachers in this way is like an adventure!