Lesson

# Clip 16/16: Adding and Subtracting Fractions Using a Line Plot: PostLesson Debrief

## Overview

After the lesson, Mallory reflects on her students’ learning with a colleague. She expresses surprise that some students confused the purposes of a number line and a line plot. She also observes that as several students modeled their solutions, they were hesitant to try a line plot as a strategy. She discusses potential next steps for her instruction, spending more time on creating and analyzing models using data.

## Teacher Commentary

When I’m having my students model their solutions, the kids want to solve it numerically, and then they want to create a model that matches their solution. But I’m teaching them that we use a model to justify why we got that as a solution, so that if we use a model accurately, and our model comes up with a similar solution as our numerical solution, then we found the correct answer that we know to be true. Like, that's our answer. But a lot of the students wanted to model the answer. I then ask them, “Why did you draw that? How does your numerical expression lend itself to that final model?”

So, having them represent with different colors and teaching them how to label things, whether it’s label your number with words or label your visuals with sections of the three-fourths. I'm teaching them all these different ways that they can participate in. So that something hopefully will click.