Lesson 1
Multiples of a Number
Lesson Purpose
Lesson Narrative
In grade 3, students learned how to find the area of a rectangle by tiling and found that multiplying the side lengths yields the same result.
The purpose of this lesson is for students to apply their understanding of area and multiplication to build rectangles and find their area. As students consider the areas of rectangles with a given side length, they explore the idea of multiples. Students learn that a multiple of a number is the result of multiplying that whole number by another.
While students are introduced to the term multiple in this lesson, they work more with it in upcoming lessons. They do not need to have a formal understanding of the term in this lesson. In upcoming lessons, students also explore and learn the terms factor and factor pair. In this lesson, they refer to them as side lengths within the context of area.
Math Community
Prepare a space, such as a piece of poster paper, titled “Mathematical Community” and a Tchart with the headers “Doing Math” and “Norms” as shown here.
The two sections encourage the students and teacher to be mindful that both respective parties are responsible for the way math is done in the classroom.
 Representation
 MLR2
Activity 2: What Areas Can You Build?
Learning Goals
Teacher Facing
 Find areas of different rectangles with a given a side length.
 Understand that the area of a rectangle is a multiple of each of its side lengths.
Student Facing
 Let’s build some rectangles.
Required Materials
Required Preparation
Activity 1:
 Each group of 2 needs at least 36 tiles.
Activity 2:
 Each group of 2 needs at least 36 tiles from the previous activity.
CCSS Standards
Lesson Timeline
Warmup  10 min 
Activity 1  20 min 
Activity 2  15 min 
Lesson Synthesis  10 min 
Cooldown  5 min 
Teacher Reflection Questions
Suggested Centers
 Can You Build It? (3–5), Stage 2: Multiple Rectangles (Addressing)
 Can You Build It? (3–5), Stage 1: Rectangles (Supporting)
 Capture Squares (1–3), Stage 7: Multiply with 6–9 (Supporting)
Print Formatted Materials
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Additional Resources
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