Human Energy Systems | Activity 4.1

Target Student Performance

Students apply the large-scale Four Questions to two patterns in the Keeling curve (showing atmospheric CO2 concentrations): the annual cycle and the long-term trend.

Resources You Provide

Resources Provided

Recurring Resources


Print one copy of Big Idea Probe: What Would Happen if We Cut Fossil Fuel Use in Half per student if you are using it and one copy of the Learning Tracking Tool for Human Energy Systems per student. Prepare computer with an Internet connection to view the videos online.


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.


This introductory activity has several opportunities for formative assessment:

  • Use the ideas students share about patterns in the Keeling curve (Slide 9) as a “baseline” for where their understanding is at this point. Even with the jigsaw activity in Lesson 2, students may still be “warming up” to the data presented in this graph. Use this activity to determine where their ideas are at this point in the unit. They may still be uncertain about what the two different lines in the graph mean and represent, and what causes the patterns.
  • Students’ ideas about the questions on Slide 11 will give you an initial view of how students are thinking about the causes for the patterns in the Keeling curve. This will be the main focus for Activities 4.3 and 4.5.
  • Students’ answers to the Big Ideas Probe will provide an initial view of students’ approaches to predicting how changes in fossil fuel emissions will affect CO2 concentrations in the future. This will be the main focus for Activities 4.4 and 4.5.

  • Break students up into groups and have each group summarize the main takeaways from each slide 3-7. Have the groups share these summaries with the rest of the class.
Extending the Learning

The New York Times has an interesting article on Charles David Keeling and his research: The Keeling Curve is often mentioned in the news and other media. Have students bring in articles that mention how many parts per million of carbon dioxide are currently in the atmosphere.