Unit 3, Lesson 17
Make 10 to Add
Grade 1
Preparation
Lesson Narrative
In previous lessons, students recognized the structure of teen numbers and used the structure to find the sum of three numbers. In this lesson, students use the structure of the 10-frame to find the sum of two addends when one addend is 9. Students come to see that when they find the sum of two addends, they can decompose one addend to make 10 with the other addend (associative property). For example, . When students identify and use equivalent expressions, they look for and make use of structure (MP7), and here they repeatedly make 10 to find the value of expressions (MP8).
Student methods are recorded with equations. It may also be helpful to represent how one addend is decomposed in order to make a ten.
- Engagement
- MLR7
- Describe (orally) patterns when adding one-digit numbers to 9.
- Explain (orally) strategies for solving Put Together, Total Unknown problems within 20 that involve making a ten.
- Let’s look for patterns and think about making 10 as we add.
Required Materials
Required Preparation
- Each group of 2 needs a set of Number Cards (1-10). Do not use the 0 cards.
Suggested Centers
NoneTeacher Reflection Questions
What was the best question you asked students today? Why would you consider it the best one based on what students said or did?