# Lesson 13

Center Day 2 (optional)

## Warm-up: True or False: Two or False (10 minutes)

### Narrative

The purpose of this True or False is to elicit strategies and understandings students have for adding with multiples of 2 and 2 equal addends. These understandings help students deepen their understanding of the properties of operations, fluency within 20, and will be helpful practice as students develop foundations for multiplication.

### Launch

• Display one statement.
• “Give me a signal when you know whether the statement is true and can explain how you know.”
• 1 minute: quiet think time

### Activity

• Share and record answers and strategy.
• Repeat with each statement.

### Student Facing

Decide if each statement is true or false. Be prepared to explain your reasoning.

• $$2 + 2 + 2 + 2 = 4 + 4$$
• $$2 + 2 + 2 = 3 + 3$$
• $$2 + 2 + 2 + 2 + 2 + 2 = 5 + 5$$

### Student Response

For access, consult one of our IM Certified Partners.

### Activity Synthesis

• “How can you explain your answer without finding the value of both sides?”

## Activity 1: Centers: Choice Time (40 minutes)

### Narrative

The purpose of this activity is for students to have another chance to practice skip-counting by 2, 5, and 10 and addition and subtraction within 1,000.

### Required Materials

Materials to Gather

### Required Preparation

Gather materials from:

• Write Numbers, Stage 4
• Target Numbers, Stages 6 and 7
• Five in a Row, Stages 7 and 8
• How Close, Stage 4

### Launch

• “Now you will choose from centers we have already learned.”
• Display the center choices in the student book.
• “Think about what you would like to do first.”
• 30 seconds: quiet think time

### Activity

• Invite students to work at the center of their choice.
• 1520 minutes: center work time
• “Choose what you would like to do next.”
• 1520 minutes: center work time
• If time allows, have students choose a third center to work on.

Choose a center.

Write Numbers

Target Numbers

Five in a Row

How Close

### Activity Synthesis

• Invite 2-3 students to share their favorite method for adding and subtracting within 1,000.

## Lesson Synthesis

### Lesson Synthesis

“We have learned a lot about addition and subtraction this year. What are some important things we need to remember about addition and subtraction?”

Share and record responses.