Lesson 9

The purpose of this warm-up is for students to make connections between bar graphs and picture graphs. While students may notice and wonder many things about these graphs, focus the synthesis on how the graphs represent the same data in different ways. This conversation leads directly into the next activity, in which students will read and interpret data represented in bar graphs.

• Groups of 2
• Display the image.
• “What do you notice? What do you wonder?”
• 1 minute: quiet think time

• "Discuss your thinking with your partner."
• 1 minute: partner discussion
• Share and record responses.

• “The graph on the right is called a bar graph. A bar graph is a way to show how many in each group or category using the length of rectangles.”
• “How is the data represented differently in the bar graph compared to the picture graph?” (The number of objects are shown on the scale on the left instead of in pictures. We don’t have to count.)

The purpose of this activity is for students to write true statements to show what they can learn about the data in a bar graph. In the synthesis, students match their peers' statements to the graph they think they came from and explain how they know using the features of the graph (MP2, MP3). In order to have a variety of different statements to share in the synthesis, look for ways to encourage students to write statements that combine multiple categories or compare categories. Share examples using the bar graph from the warm-up as needed (for example, 8 total students liked fish or lizards as their favorite pet.)

• Groups of 3
• Assign each group a graph to interpret.

• “With your group, write as many statements as you can to show what can be learned about the students' field trip choices from your graph.”
• "We will share the statements you write with the class to see if they can guess which graph you interpreted."
• 8 minutes: small-group work time
• Monitor for students who create a variety of different statements, including those that combine or compare categories, to share during the activity synthesis. Choose at least 1 group for each graph.

• Invite one of the previously identified groups to share 2–3 of their statements.
• “Which graph did this group interpret? How do you know?” 
• Repeat, varying groups that interpreted different graphs, as time permits.

The purpose of this activity is for students to interpret data represented in a bar graph and answer questions about the data. In previous work with picture graphs, students had to count the pictures in order to answer “how many” questions. During this activity, identify students who recognize that they can use the scale (numbers on the side) instead of counting each line or section of the bar. Ask these students to share during the synthesis. It is important for students to consider the benefits of using a bar graph compared to a picture graph.
This activity uses MLR6 Three Reads. Advances: reading, listening, representing.

• Groups of 2
• Display Our Favorite Seasons bar graph, without revealing the questions.

MLR6 Three Reads

• “Here is a bar graph showing data collected about students’ favorite seasons. We are going to read this graph 3 times.”
• 1st Read: “Take a moment to read the data displayed by this graph.”
• “What is this graph about?”
• 1 minute: partner discussion
• Listen for and clarify any questions about the context.
• 2nd Read: “Read and interpret the bar graph a second time. What can be counted or measured in this situation?” (number of students who voted for each season, number of students who voted)
• 30 seconds: quiet think time
• 2 minutes: partner discussion
• Record quantities on a display for all to see.
• 3rd Read: Read the question(s) aloud.
• “How can we use the bar graph to answer these questions?”
• 30 seconds: quiet think time
• 1–2 minutes: partner discussion
• “Use the bar graph to answer the questions.”
• 7 minutes: independent work time
• Monitor for students who:
  • count each section of the bars
  • use the scale
  • create equations to record how they combine categories
• If some students finish early, you can ask them to write statements about what can be learned or other questions that can be asked about the data in the bar graph.

• Invite previously identified students to share how they used the bar graph to find how many students voted for summer.
• Invite previously identified students to share how they found the total number of students who voted.