Lesson 12
Represent Division of Unit Fractions by Whole Numbers
Lesson Purpose
Lesson Narrative
In the previous lesson, students solved problems about dividing a unit fraction by a whole number in a way that made sense to them. In this lesson, students use tape diagrams to represent division of a unit fraction by a whole number. The tape diagrams used to represent the problems are familiar to students from earlier grades. Here is a tape diagram showing \(\frac{1}{4}\), one out of 4 pieces is shaded:
One way to show \(\frac{1}{4} \div 3\) is to divide the \(\frac{1}{4}\) into 3 equal pieces.
To see how much is shaded we can divide all of the \(\frac{1}{4}\)s and see that \(\frac{1}{4} \div 3 = \frac{1}{12}\).
Students use these diagrams to understand this series of steps representing division of a unit fraction by a whole number throughout the lesson.
- Engagement
Activity 2: Priya’s Work
Learning Goals
Teacher Facing
- Make sense of diagrams that represent division of a unit fraction by a whole number.
Student Facing
- Let’s make sense of diagrams that represent division of a unit fraction by a whole number.
Required Preparation
CCSS Standards
Addressing
Lesson Timeline
| Warm-up | 10 min |
| Activity 1 | 10 min |
| Activity 2 | 10 min |
| Activity 3 | 15 min |
| Lesson Synthesis | 10 min |
| Cool-down | 5 min |
Teacher Reflection Questions
Suggested Centers
- Rolling for Fractions (3–5), Stage 4: Multiply Fractions (Addressing)
- Compare (1–5), Stage 4: Divide within 100 (Supporting)
- How Close? (1–5), Stage 7: Multiply Fractions and Whole Numbers to 5 (Supporting)