Lesson plan

# 9. Fluently add numbers within 20 by making a ten (FP)

teaches Common Core State Standards MP7 http://corestandards.org/Math/Practice/MP7
teaches Common Core State Standards MP3 http://corestandards.org/Math/Practice/MP3
teaches Common Core State Standards 1.OA.B.4 http://corestandards.org/Math/Content/1/OA/B/4
teaches Common Core State Standards 1.OA.B.3 http://corestandards.org/Math/Content/1/OA/B/3

# 9. Fluently add numbers within 20 by making a ten (FP)

This lesson helps to build fluency with whole number addition. A structured equation model is used here because it highlights when and how to use the Make a Ten addition strategy. This work develops students' understanding that using strategies can make adding easier.

Students engage in Mathematical Practice 7 (Look for and make use of structure) as they decompose one addend so part of it can make a ten with the other addend to make adding easier. Students will build on their knowledge of place value to mentally add a single digit to 10 and use a structured equation model to learn the steps to apply the Make a Ten strategy to solve addition equations.

Key vocabulary:

• decompose
• equation
• make a ten
• mental math
• number bonds