# Lesson 22

Center Day 4

### Lesson Purpose

The purpose of this lesson is for students to use place value understanding to compare and write numbers.

### Lesson Narrative

In the first activity, students learn a new center called Mystery Number. In this center, students give clues to help their partner guess a two-digit number. In the second activity, students choose between center activities introduced earlier in the unit.

### Learning Goals

Teacher Facing

• Compare numbers within 99.
• Use place value understanding to identify two-digit numbers.

### Student Facing

• Let’s play games about tens and ones.

### Required Materials

Materials to Gather

Materials to Copy

• Mystery Number Stage 1 Directions

### Required Preparation

Activity 2:

• Gather materials from previous centers:
• Mystery Number, Stage 1
• Get Your Numbers in Order, Stage 1
• Greatest of Them All, Stage 1

Addressing

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 25 min Lesson Synthesis 10 min

### Teacher Reflection Questions

As you finish up this unit, reflect on the norms and activities that have supported each student in learning math. List ways you have seen each student grow as a young mathematician throughout this work. List ways you have seen yourself grow as a teacher. What will you continue to do and what will you improve upon in the next unit?

### Print Formatted Materials

For access, consult one of our IM Certified Partners.

### Additional Resources

 Google Slides For access, consult one of our IM Certified Partners. PowerPoint Slides For access, consult one of our IM Certified Partners.