# Lesson 19

Problemas-historia y ecuaciones

### Lesson Purpose

The purpose of this lesson is for students to write two different equations to match a story problem.

### Lesson Narrative

Students are encouraged to write an equation with a symbol for the answer to the question, but they are not required to. Students may write a second equation using the relationship between addition and subtraction, the commutative property, or the meaning of the equal sign.

- Engagement

- MLR6

Activity 1: Lotería

### Learning Goals

Teacher Facing

- Solve a variety of story problem types.
- Write two different equations to match a story problem.

### Student Facing

- Escribamos 2 ecuaciones que correspondan a cada problema-historia.

### Required Materials

Materials to Gather

### 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

How do you see your students demonstrating an understanding of the relationship between addition and subtraction? Are students working flexibly with addition and subtraction in order to find missing values?