Lesson 7
Fracciones como sumas
Lesson Purpose
Lesson Narrative
In previous lessons, students expressed a fraction \frac{a}{b} as a product of a unit fraction \frac{1}{b} and a whole number a. In this lesson, students transition to seeing a fraction \frac{a}{b} as a sum of unit fractions and non-unit fractions with the same denominator. Students see that a fraction with a numerator greater than 1 can be decomposed into sums in different ways. They write equations to record the decomposition (for example, \frac{4}{6} = \frac{3}{6} + \frac{1}{6}). Later, they write equations to represent addition of fractions with the same denominator.
- Action and Expression
- MLR7
Learning Goals
Teacher Facing
-
Recognize that a fraction can be decomposed into a sum of fractions with the same denominator.
-
Write equations to represent fraction decomposition.
Student Facing
- Escribamos fracciones como sumas.
Required Materials
Materials to Gather
Required Preparation
Activity 1:
- Gather \frac{1}{4}-cup and \frac{3}{4}-cup measuring cups, if available.
CCSS Standards
Lesson Timeline
| Warm-up | 10 min |
| Activity 1 | 20 min |
| Activity 2 | 15 min |
| Lesson Synthesis | 10 min |
| Cool-down | 5 min |
Teacher Reflection Questions
Suggested Centers
- Rolling for Fractions (3–5), Stage 2: Multiply a Fraction by a Whole Number (Addressing)
- Estimate and Measure (1–4), Stage 3: Quarter Inches (Supporting)
- Target Measurements (2–5), Stage 2: Quarter Inches (Supporting)