Lesson 14

Lesson Purpose

The purpose of this lesson is for students to solve Compare, Difference Unknown story problems and match addition and subtraction equations to the problems.

Lesson Narrative

In previous lessons, students solved Compare problems and wrote equations to match. They considered counting on and counting back to find the difference. This lesson builds on previous work done in this unit by asking students to find two equations that match a story problem and describe how each equation relates to the story problem.

• Engagement
• MLR2

Activity 1: Is It Addition or Subtraction?

Learning Goals

Teacher Facing

• Match addition and subtraction equations to a story problem.
• Solve Compare, Difference Unknown story problems.

Student Facing

• Let’s solve story problems and match them to addition and subtraction equations.

Required Materials

Materials to Gather

Required Preparation

Activity 3:

• Gather materials from previous centers:
• Capture Squares, Stage 1
• Math Stories, Stage 4
• Shake and Spill, Stages 3 and 4

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

What did you say, do, or ask during the lesson synthesis that helped students be clear on the learning of the day?