Unit 7, Lesson 9
Add 3-Digit Numbers
Grade 2
Preparation
Lesson Narrative
In previous lessons, students added a two-digit number and a three-digit number. They shared and compared methods and representations that showed adding by place and composing units.
In this lesson, students practice adding within 1,000. They add 2 three-digit numbers, using methods based on place value and the properties of operations. Students also compare diagrams and drawings to written methods that use equations and expressions. They analyze work to identify why a method was successful and identify any errors if the method was not successful (MP3).
- Engagement
None
- Critique (orally and in writing) methods for adding three-digit numbers.
- Explain (orally) strategies for adding 2 three-digit numbers that include composing two units when adding by place.
- Let’s practice adding within 1,000.
Required Preparation
None
Teacher Reflection Questions
Reflect on who participated in math class today. What assumptions are you making about those who did not participate? How can you leverage each student’s ideas to support them in being seen and heard in math class from now on?