Lesson 27
Center Day 4
Lesson Purpose
The purpose of this lesson is for students to practice adding and subtracting within 20.
Lesson Narrative
Students learn new stages in two centers that focus on adding and subtracting within 20. Students have opportunities to practice methods such as finding the difference by counting on, taking away, making 10, and using addition facts.
- Action and Expression
Learning Goals
Teacher Facing
- Add and subtract within 20.
Student Facing
- Let’s play games to practice addition and subtraction.
Required Materials
Materials to Gather
- Connecting cubes or two-color counters
- Double 10-frames
- Materials from a previous lesson
- Materials from previous centers
- Number cards 0–10
Materials to Copy
- How Close? Stage 2 Recording Sheet
- Compare Stage 2 Subtraction Cards to 20
Required Preparation
Activity 2:
- Create a set of Compare Stage 2 Subtraction Cards for each group of 2.
- Each group of 2 needs a set of Compare Stage 2 Addition Cards from a previous lesson.
- Gather materials from previous centers:
- Compare, Stage 1
- How Close? Stages 1 and 2
- Five in a Row, Stages 1-3
Lesson Timeline
| Warm-up | 10 min |
| Activity 1 | 15 min |
| Activity 2 | 25 min |
| Lesson Synthesis | 10 min |
Teacher Reflection Questions
Reflect on who got to do math today in class. What norms or routines allowed those students to engage in the mathematics? How can you adjust these norms and routines so all students do math tomorrow?