Lesson 12
Resolvamos problemas
Lesson Purpose
The purpose of this lesson is for students to solve problems that involve adding and subtracting fractions with unlike denominators.
Lesson Narrative
In this lesson, students apply their understanding of fraction addition and subtraction to solve multi-step problems. They work with fractions and mixed numbers and make estimates as well as finding the value of sums and differences. Students find the sums and differences in a way that makes sense to them. They will choose common denominators and can also use techniques they have seen in earlier lessons such as adding on to make a whole number.
- Representation
- MLR6
Learning Goals
Teacher Facing
- Solve problems involving addition and subtraction of fractions with unlike denominators.
Student Facing
- Resolvamos más problemas sumando y restando fracciones que tienen denominadores diferentes.
Required Preparation
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
What strategies did most students use to add and subtract fractions today? What strategies did you anticipate? Which did you not anticipate?
Suggested Centers
- How Close? (1–5), Stage 9: Add Fractions to 5 (Addressing)
- Creating Line Plots (2–5), Stage 3: Eighth Inches, Add and Subtract (Supporting)