Lesson 6
Multiply Fractions
Lesson Purpose
The purpose of this lesson is for students to calculate areas of rectangles where both side lengths are non-unit fractions.
Lesson Narrative
As in previous lessons, students represent a product of fractions with a diagram. This diagram represents the product \frac{3}{6} \times \frac{4}{5}. The diagram shows \frac{3}{6} of \frac{4}{5} of the square so that’s \frac{3}{6} \times \frac{4}{5}. The number of shaded pieces is 3 \times 4, the product of the numerators. The number of pieces in the whole square is 6 \times 5, the product of the denominators. So the value of the product can also be written as \frac{3 \times 4}{6 \times 5}. In the first activity, students relate expressions to the area in diagrams like this and then they use this structure to find products of non-unit fractions in the second activity.
- Action and Expression
Learning Goals
Teacher Facing
-
Represent multiplication of two non-unit fractions with expressions.
Student Facing
- Let’s multiply two non-unit fractions using diagrams and expressions.
Required Preparation
CCSS Standards
Addressing
Lesson Timeline
Warm-up | 10 min |
Activity 1 | 15 min |
Activity 2 | 20 min |
Lesson Synthesis | 10 min |
Cool-down | 5 min |
Teacher Reflection Questions
Suggested Centers
- Rolling for Fractions (3–5), Stage 4: Multiply Fractions (Addressing)
- How Close? (1–5), Stage 7: Multiply Fractions and Whole Numbers to 5 (Supporting)