Lesson 11
How Did You Do That?
Lesson Purpose
The purpose of this lesson is for students to add 2 two-digit numbers, with composing a ten, using methods based on place value and properties of operation and make sense of equations that represent addition methods.
Lesson Narrative
In previous lessons, students added 2 two-digit numbers using methods based on place value and properties of operations. In this lesson, students add 2 two-digit numbers and make sense of the equations that represent addition methods.
The cool-down should be completed before the lesson synthesis.
- Engagement
- MLR7
Learning Goals
Teacher Facing
- Add 2 two-digit numbers using methods based on place value and properties of operations.
- Make sense of equations that represent addition methods.
Student Facing
- Let’s add two-digit numbers and make sense of equations.
Required Materials
Materials to Gather
Required Preparation
Lesson Timeline
| Warm-up | 10 min |
| Activity 1 | 15 min |
| Activity 2 | 20 min |
| Lesson Synthesis | 10 min |
| Cool-down | 5 min |
Teacher Reflection Questions
How did your students represent their thinking today? How might you support them in creating more efficient representations?