# Lesson 10

Center Day 2

### Lesson Purpose

The purpose of this lesson is for students to practice measuring and adding within 100.

### Lesson Narrative

Students learn a new center called Estimate and Measure, where they choose an object and a length unit to measure it with. They estimate the length of the object before measuring to find the actual length. Students then choose from previously introduced centers focusing on adding within 100.
• Action and Expression
• MLR8

### Learning Goals

Teacher Facing

• Measure length by iterating same-size length units without gaps or overlaps.

### Student Facing

• Let’s measure the length of objects.

### Required Materials

Materials to Gather

Materials to Copy

• Estimate and Measure Stage 1 Recording Sheet

### Required Preparation

Activity 1:

• Gather or identify objects of various lengths that are less than 20 connecting cubes long (pencils, markers, books, glue, scissors, shoe, tape dispenser).

Activity 2:

• Gather materials from:
• How Close? Stages 1–3
• Target Numbers, Stages 1–3
• Five in a Row, Stages 1–6

### Lesson Timeline

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

### Teacher Reflection Questions

As students worked together today, where did you see evidence of the mathematical community established over the course of the school year?