Lesson 17

• 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

• “Discuss your thinking with your partner.”
• 2–3 minutes: partner discussion
• Record responses.

• 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.)

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:

• Add to, Change Unknown and Put Together, Addend Unknown
• 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.

• 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.

• “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.

• 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.)

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).

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

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

• "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.

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