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4th Grade Math – Classifying Triangles

Clip 4/18: Lesson: Classifying Triangles Part 1A

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Hillary Lewis begins her formative re-engagement lesson with fourth-grade students, asking them to revisit a grid poster that they had co-constructed the week before showing types of triangles.

Students engage in a partner turn-and-talk and then share out what they remember from the previous week. One student shares that “We were sorting them by angles: into acute, right, and obtuse. And then you look at the sides to sort them with scalene, isosceles, and equilateral.”

Hillary challenges the students to develop and share definitions for each of these terms.

Teacher Commentary

Hillary Lewis

Teaching a colleague’s students brings challenges, because I don’t know the children as well. In this classroom, there were two students who recently arrived at the school who didn't speak English well yet. To support and engage all learners, I try to avoid yes/no questions. I like to ask them to tell me about how they thought about something. "How did you think about that? Tell me more," those kinds of things.

I often talk about, "Tell me what your brain was thinking about." I almost talk about the brain as if it's a separate thing from ourselves, and I feel like it frees kids up. Like, “If my brain got mixed up, that's not a reflection of me. If my brain froze, it's not a reflection of me.”