# Clip 5/18: Lesson: Classifying Triangles Part 1B

## Overview Download Transcript (PDF)

Hillary Lewis continues her formative re-engagement lesson on classifying triangles with fourth- grade students, reminding them of their prior lesson in which they placed different triangles in different places on a grid. She shares two examples of how “other students” categorized triangles and asks the students to evaluate their thinking: “What do you think about the placement of these triangles? When you respond, just talk about one triangle at a time. What do you think they understood, what do you think they misunderstood?”

Students respond with their ideas about where the other students got “mixed up” or what they “didn’t understand.” Students build on each other’s thinking and responses.

## Teacher Commentary

**
Hillary Lewis
**

Being able to talk about what the brain is doing as if it's a third person, it decreases that anxiety, that fear or feeling of, if I'm doing this wrong.

If the individual is stuck, I may ask them if they want to think about it longer, or if they want to “phone a friend” for help. I usually let them choose their own partner to help… somebody else who might be able to explain their thinking if they’re having trouble explaining the thinking.