# Lesson 17

How Do the Stories Compare?

## Warm-up: Which One Doesn’t Belong: Equations (10 minutes)

### Narrative

This warm-up prompts students to analyze and compare equations. In addition to calculating the value of each expression, students also think about the structure of each expression, including both the operations and the numbers.

### Launch

• Groups of 2
• Display the image.
• “Pick one that doesn’t belong. Be ready to share why it doesn’t belong.”
• 1 minute: quiet think time

### Activity

• 2–3 minutes: partner discussion
• Record responses.

### Student Facing

Which one doesn’t belong?

1. $$6 + 4 = 10$$
2. $$10 - 4 = 6$$
3. $$2 + 2 + 2 = 6$$
4. $$6 = 2 + 4$$

### Activity Synthesis

• Display equations A and B.
• “How are the equations the same? How are they different?” (They are related facts. They both have a total of 10 and 6 and 4 as parts. One is addition and one is subtraction.)

## Activity 1: Compare Stories (20 minutes)

### Narrative

The purpose of this activity is for students to compare different story problems to determine how they are the same and different. The stories being compared represent problem types students have worked with in previous lessons, specifically:

• Take From, Result Unknown and Take Apart, Addend Unknown

As students discuss the similarities of the story problems, they may notice the structures of the problems are connected, the same operations can be used to solve the problems, or that the answer is in the same place in the equation.

During the synthesis, students discuss a Put Together, Both Addends Unknown problem and consider how the structure of the problem is different from the others.

MLR2 Collect and Display. Collect the language students use to talk about the problems. Display words and phrases such as: “sort,” “add,” “subtract,” “more,” “less,” “story,” “numbers.” During the synthesis, invite students to suggest ways to update the display: “What are some other words or phrases we should include?”, etc. Invite students to borrow language from the display as needed as they discuss the new problem.

### Launch

• Groups of 2
• "Think about games you like to play when we have free time at school. They can be indoor or outdoor games."
• 30 seconds: quiet think time
• Share responses and record in two categories, indoor games and outdoor games.

### Activity

• “You and your partner are going to read two pairs of story problems about games students play at school. You are going to think about how the pairs of story problems are the same and different.”
• Read the first two story problems to the class.
• 1 minute: quiet think time
• “Talk to your partner about how the two problems are the same and different.”
• 4 minutes: partner discussion
• Share responses.
• Repeat with the next two problems.

### Student Facing

1. Compare these stories about playing 4 corners.

There are 6 students playing 4 corners.
Some more students come to play.
Now there are 9 students playing 4 corners.
How many students came to play?

9 students are playing 4 corners.
7 students are waiting in a corner.
The other students are still deciding which corner to pick.
How many students are still deciding which corner to pick?

• How are these problems alike?
• How are they different?

Be prepared to share your thinking.

There were 9 students playing charades.
6 students leave to play something different.
How many students are playing charades now?

5 students are on Team A.
The rest of the students are on Team B.
How many students are on Team B?

• How are these problems alike?
• How are they different?

Be prepared to share your thinking.

### Activity Synthesis

• Display “9 students are playing charades. Some students act out sports and some act out animals. How many students act out sports? How many act out animals?”
• “How is this problem the same as the others? How is it different?” (It still has 9 as the total. This time, you don’t know either part.)

## Activity 2: Outdoor Games (20 minutes)

### Narrative

The purpose of this activity is for students to solve a story problem and write an equation to match it. Students are divided into nine groups and each group gets one of the story problem cards from the blackline master. Students individually solve the story problem and write an equation to match it before creating a poster with their group. During the synthesis, students explain how the equations match the story problem. When students recognize that the numbers in the equations represent specific quantities in the story problems, they reason abstractly and quantitatively (MP2).

Engagement: Internalize Self-Regulation. Provide students an opportunity to self-assess and reflect on their own progress. For example, ask students to check over their work to make sure they used drawings, numbers, or words to show their thinking, and also included at least one equation to show how they solved the problem.
Supports accessibility for: Organization, Conceptual Processing

### Required Materials

Materials to Gather

Materials to Copy

• Story Problem Cards Grade 1

### Required Preparation

• Create one set of Story Problem Cards from the blackline master.

### Launch

• Groups of 2–4, so there are 9 groups
• Give each group tools for creating a visual display and one of the story problems.

### Activity

• "Now we will solve some problems about games students play outdoors."
• “Read your problem with your partner or group. Then solve the problem on your own. Show your thinking using drawings, numbers, or words. Write an equation to match the story problem.”
• 4 minutes: independent work time
• “Work with your partner or group to agree on the answer to the story problem and make a display of your work. If you showed your thinking in different ways, include them all on the poster.”
• 6 minutes: small-group work time
• Monitor for 2–3 posters in which the representation is clear, labeled, and has accurate equations.

### Student Facing

Show your thinking using drawings, numbers, or words.

Equation: ________________________________

### Activity Synthesis

• Display previously identified posters.
• “How does the equation each group wrote match the story problem?”

## Lesson Synthesis

### Lesson Synthesis

9 students are jumping Double Dutch.
4 students are jumping rope by themselves.
How many fewer students are jumping rope on their own than playing Double Dutch?

Write $$9 - 4 = \boxed{{5}}$$ and $$\boxed{{5}} + 4 = 9$$.

“Today we used different equations to represent story problems. How do each of these equations match this problem?”