Lesson 25
How Do You Want to Subtract?
Lesson Purpose
The purpose of this lesson is for students to use subtraction methods flexibly to find differences.
Lesson Narrative
Students apply their learning from the unit to flexibly use methods to subtract within 20. There is not one correct method to use, as it is based on each individual student's understanding of the concepts of subtraction and their known facts. It is helpful for students to listen to and make sense of others’ reasoning about which method they used (MP3). In the first activity, students find differences given expressions. In the second activity, students apply subtraction methods as they solve story problems with the unknown in all positions.
- Engagement
- MLR8
Learning Goals
Teacher Facing
- Use subtraction methods flexibly to find differences based on the numbers in a given problem.
Student Facing
- Let’s use subtraction methods that work for the numbers in a problem.
Required Materials
Materials to Gather
Required Preparation
Lesson Timeline
| Warm-up | 10 min |
| Activity 1 | 20 min |
| Activity 2 | 15 min |
| Lesson Synthesis | 10 min |
| Cool-down | 5 min |
Teacher Reflection Questions
How did your students represent their work today? How might you support them in creating more efficient representations?
Print Formatted Materials
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Additional Resources
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