Lesson Plan

Decomposing Numbers

Why make things harder on ourselves? Teach your students to decompose numbers to make math easier! Use this as a stand alone lesson or a pre-lesson for *Decompose to Multiply: 6, 7, 8, and 9.*
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This lesson can be used as a pre-lesson for the Decompose to Multiply: 6, 7, 8, and 9 lesson plan.
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This lesson can be used as a pre-lesson for the Decompose to Multiply: 6, 7, 8, and 9 lesson plan.



Students will be able to decompose factors to find multiples of six, seven, eight, and nine.


Students will be able to explain how to decompose numbers using peer supports.


(4 minutes)
Teach Background Knowledge TemplateWrite Student-Facing Language Objectives Reference
  • Invite students to do a quick number talk by looking at a set of dots displayed on the document camera. Explain that they will only briefly see a set of dots because you don't want them to count the dots individually. Tell them that they will then be asked to share how many dots they saw. Then they will explain how they saw the pattern of dots and figured out the total number. Emphasize that they need to group the dots in their minds to find the total number rather than counting each individual dot.
  • Display a set of dots (such as three rows of four dots) for about two or three seconds.
  • Engage the students in a class discussion about how many dots they saw and the patterns in which they saw them. As students share their explanations, create visuals on the board and ask them to verify if you are capturing their visual correctly.
  • Explain that you did the number talk about the dots because you want to point out how we all see numbers and patterns in different ways. We can all see a collection of dots, but we may see the patterns, or how the set is broken up, differently.
  • Share the Language Objective for the lesson and explain that today students will learn how to explain how to decompose numbers.

Related Guided Lesson

Number Sense 2

1 game
3 online exercises
5 printable worksheets
View Guided Lesson
third grade
Subject Math