# Lesson 20

¿Cuál es la historia?

### Lesson Purpose

The purpose of this lesson is for students to write story problems to match equations.

### Lesson Narrative

Students write story problems using given mathematical information: either an equation, or a number in an equation. In previous lessons, students solved a variety of story problems, matched equations with unknowns to story problems, and wrote equations to match story problems. In Activity 1, students build on their understanding of equations with unknowns by writing story problems that match an equation. In Activity 2, students write story problems that match a given answer. This lesson is the first time students write story problems to match equations or the answer to an equation.

• Engagement
• MLR7

### Learning Goals

Teacher Facing

• Write a story problem to match an equation.

### Student Facing

• Escribamos problemas-historia que correspondan a ecuaciones.

### Required Materials

Materials to Gather

### Required Preparation

Activity 3:

• Gather materials from previous centers:
• Capture Squares, Stages 1 and 2
• Shake and Spill, Stages 3 and 4
• What's Behind My Back, Stage 2

Building Towards

### Lesson Timeline

 Warm-up 10 min Activity 1 15 min Activity 2 10 min Activity 3 15 min Lesson Synthesis 10 min Cool-down 0 min

### Teacher Reflection Questions

Think about which students haven’t shared their thinking in class lately. Were there missed opportunities to highlight their thinking during recent lessons? How can you take advantage of those opportunities when they arise?