Lesson 7

The purpose of this How Many Do You See is for students to subitize or use grouping strategies to describe the images they see.

When students notice that some of the dots are in equal groups and skip-count to find the total number of dots they are looking for and making use of structure (MP7).

• Groups of 2
• “How many do you see? How you do see them?”  
• Flash the image.
• 30 seconds: quiet think time

• Display the image. 
• “Discuss your thinking with your partner.”
• 1 minute: partner discussion
• Record responses.
• Repeat for each image.

• “How did thinking about groups help you find the total number of dots?” (Some of the dots were in groups and some were not. I used skip-counting to count the groups that were the same size, then added on the rest of the dots.)
• Consider asking:
  • “Who can restate the way _____ saw the dots in different words?”
  • “Did anyone see the dots the same way but would explain it differently?”

The purpose of this activity is for students to use data presented in scaled bar graphs to solve one-step “how many more” and “how many fewer” problems. Students use scaled bar graphs that they created in the previous lesson that contain data about the favorite time of the year. Answering questions about a graph with which they are familiar prepares them for the next task in which they answer questions about a new graph. This activity provides an opportunity for formative assessment of students addition and subtraction methods. In grade 2, students were expected to fluently add and subtract within 100.

Students will need their Favorite Time of the Year graphs from the previous lesson.

• Groups of 2
• Make sure that students have their Favorite Time of the Year graphs from a previous lesson.
• “Take a minute to look over the questions you’ll answer using the Favorite Time of the Year graph from a previous lesson.”
• 1 minute: quiet think time

• “Work with your partner to answer the questions.”
• 7–10 minutes: partner work time
• Monitor for different strategies students use to add or subtract, particularly strategies that use tens and ones.

If students find the sum of the quantities in the compare problems or do not find a value, consider asking:

• “What is this problem about?”
• “How would you describe two categories in the graph using the phrase, ‘more than’ or ‘fewer than’?”

• Have students share responses to the last 2 questions.
• “How are these questions the same? How are they different?” (They both ask about the difference between 2 categories. The first question uses “more” and the second question uses “fewer.”)
• As students share, use this as an opportunity to highlight addition and subtraction strategies in which students use tens and ones.

The purpose of this activity is for students to use data presented in scaled bar graphs to solve one-step “how many more” and “how many fewer” problems. The graph in the previous activity was familiar to students since they had created it in the previous lesson, but the graph used in this activity is new to students. Because the graph has a scale of 10, students need to estimate values that do not show an exact multiple of 10. As a result, answers may vary slightly. Accept all answers that align to reasonable estimates.

• Groups of 2
• “Look at the scaled bar graph and tell your partner one thing you notice.”
• 1 minute: partner discussion

• “Work with your partner to use the data in the bar graph to complete the first four problems.”
• 7–10 minutes: partner work time
• Monitor for different strategies students use to add or subtract, particularly strategies that use tens and ones.
• “Now, trade the questions you wrote for the fourth question with another group and answer their questions.”
• 2–3 minutes: partner work time

If students find sums for compare problems or do not find a solution, consider asking:

• “Tell me about how you started this problem?”
• “How could you use the information from the graph to solve the problem?”

• Have students share responses for the first three problems. Be sure to share a variety of reasonable estimates for the values in each category to make sure students know it’s okay if they don’t know the exact value for sure.
• Have 2–3 groups share a question they wrote and have the whole class solve it. As students share, use this as an opportunity to highlight addition and subtraction strategies in which students use tens and ones.