# Lesson 2

Sums and Differences of Fractions

### Lesson Purpose

The purpose of this lesson is for students to represent and solve problems involving the addition and subtraction of fractions. Students also reason about equivalence to compare fractions and make sense of problems.

### Lesson Narrative

In this lesson, students apply what they know about equivalence and addition and subtraction of fractions to solve problems. Throughout the lesson, students have opportunities to reason quantitatively and abstractly as they connect their representations, including equations, to the situations (MP2) and to compare their reasoning with others' (MP3).

The work of this lesson helps prepare students for adding and subtracting with unlike denominators in grade 5. If students need additional support with the concepts in this lesson, refer back to Unit 3, Section B in the curriculum materials.

• Action and Expression
• MLR8

### Learning Goals

Teacher Facing

• Add and subtract fractions and mixed numbers with like denominators.
• Compare fractions and mixed numbers by reasoning about equivalence.

### Student Facing

• Let’s practice solving problems involving fractions.

Building Towards

### 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

What strategies were students using to solve problems? What evidence did students show that they were reasoning about equivalence as they solved the problems?