Directions 1. Use the instructional model to show students where they are in the course of the unit. Show Slide 2 of the 4.1 Questions for this Lesson PPT. 2. Review what students have learned. Show Slides 3-7. Remind students that in the previous activities and lessons they used evidence to construct explanations about how increasing levels of CO2 in the atmosphere drive other changes in global systems. In this Lesson, they will examine more closely why and how CO2 levels are increasing. Before we do that, though, we will share our initial ideas about one specific Earth system: The Keeling Curve. 3. Help students identify the two patterns in the Keeling Curve. Ask students to look at the graphs on Slide 9 and to identify the patterns that they see. Use Slide 10 to provide names for the patterns: The Annual Cycle and the Long-term Trend. Optional: Show students the Pumphandle Video and discuss how the patterns in data from Hawaii are also patterns observed in many other locations on Earth. 4. Elicit students’ initial ideas about the Annual Cycle and the Long-term Trend Ask students to share their initial ideas about the first two questions on Slide 11. If you are using a Driving Question Board, you may want to record those ideas for later discussion. 5. Introduce or review the Large-scale Four Questions. Show Slide 12, pass out the Four Questions Handout with checklist, and show students the Four Questions Poster. If your students studied the Ecosystems unit, they will be familiar with the Four Questions from that unit. If they have studied other macro-scale Carbon TIME units, remind them of the Three Questions. They will use the Four Questions to define what makes a good explanation. An overview of the first column of the table—the questions themselves—will be sufficient for now. They will discuss the Four Questions later in more detail. 6. (Optional) Have students complete the Big Idea Probe: What Would Happen if We Cut Fossil Fuel Use in Half? If you decide to use the Big Idea Probe: What Would Happen if We Cut Fossil Fuel Use in Half Show Slide 13 and have students complete it and share their ideas. See Assessing the Big Idea Probe: What Would Happen if We Cut Fossil Fuel Use in Half and Using Big Idea Probes for suggestions about how to use the Big Idea Probe. 7. Have a discussion to introduce the Learning Tracking Tool for this activity. Show Slide 14 of the 4.1 Questions for this Lesson PPT. Pass out a Learning Tracking Tool for Human Energy Systems to each student. Explain that students will add to the tool after activities to keep track of what they have figured out that will help them to answer the unit driving question. Discuss goals for this lesson. Have students write the activity name in the first column, "Questions for this Lesson." Have a class discussion about what students figured out during the activity that will help them in answering the lesson driving questions: What causes the annual cycle: CO2 concentrations in Hawaii to go down every summer and up every winter? What causes the long-term trend: CO2 concentrations to go up every year? How can we predict what will happen to CO2 concentrations in the future? When you come to consensus as a class, have students record the answer in the second column of the tool. Have a class discussion about what students are wondering now that will help them move towards answering the unit driving question. Have students record the questions in the third column of the tool. Have students keep their Learning Tracking Tool for future activities. Example Learning Tracking Tool Activity What We Figured Out What We are Asking Now Activity 4.1: Questions for this Lesson Increases in atmospheric CO2 are driving changes in other Earth systems. The Keeling Curve shows both an annual cycle and a long-term upward trend in CO2 concentrations in Hawaii. What is causing the annual cycle? What is causing the long-term trend?