# Lesson 17

Center Day 3 (optional)

### Lesson Purpose

The purpose of this lesson is for students to practice adding, subtracting, and measuring length to create line plots.

### Lesson Narrative

This lesson is optional because it is an opportunity for extra practice that not all classes may need. In Activity 1, students learn stage 1 of the Creating Line Plots center. In this stage, called Inches and Centimeters, students Students measure up to 8 objects to the nearest centimeter or inch. They work with a partner to create a line plot to represent their measurement data. Then, they ask their partner 2 questions that can be answered based on their line plot. In Activity 2, students choose to continue working on Creating Line Plots, or choose between two previously introduced centers focused on estimation and measurement or a center focused on addition and subtraction.

### Learning Goals

Teacher Facing

• Add and subtract within 100.
• Estimate and measure length of objects.

### Student Facing

• Let's measure to create line plots and add and subtract within 100.

### Required Materials

Materials to Gather

Materials to Copy

• Creating Line Plots Stage 1 Recording Sheet

### Required Preparation

Activity 1:

• Gather collections of objects of various lengths. Collections could include pencils, crayons, math tools, or other classroom materials that have varying lengths.

Activity 2:

Gather materials from:
• Estimate and Measure, Stage 2
• Number Puzzles, Stages 24
• Target Measurements, Stage 1

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 20 min Lesson Synthesis 10 min

### Teacher Reflection Questions

How have centers helped deepen student understanding of the important mathematical ideas of this unit? Are there centers from this unit that students would continue to benefit from if extended into the next unit?