Prerequisite Skills:
Prior knowledge of PowerPoint

Materials and Resources Required For Unit:
Computers with Internet access, Projection system, Stella Software, PowerPoint Software, Internet handout with research sources, Internet fact collecting handout, Rubric for evaluating presentations - content and oral communication, written essay questions and Vocabulary Sheet.

Day 1: Teacher shares the pre-made Carbon Cycle PowerPoint presentation, and discusses the different influences that can effect change in the carbon cycle. Next, the teacher demonstrates the building of a Stella model. The emphasis is placed on helping students understand how to change values of stocks and flows, as well as how to graph the results.  Internet sites and other pertinent reference materials that could assist students in the creation of their carbon cycle PowerPoint presentation are introduced. These sites and reference materials will contain information related to changes in the carbon cycle and how these changes affect the environment.

Day 2: Students are placed into three biome groups: marine, terrestrial and subterranean.  Once placed in groups, students draw a career card, created by the teacher from a collection of careers related to the chosen biosphere. Students are given time to work in their groups researching needed information utilizing specific sites on the Internet.  Researched information will be used to build the PowerPoint presentation and assist students in choosing figures they might use when manipulating the Stella model. Students will have a worksheet to help direct them in researching the various sites. Documenting where their best information is located.

Day 3: Students begin building their PowerPoint Presentation utilizing information collected from their Internet searches.  Students are required to place hyperlinks to the sites they used to collect facts. The hyperlinks will serve as bibliographies.

Day 4: Students begin manipulating figures in the Stella model, graphing the various results of the changing figures. Students are required to simulate both a growth in the atmospheric carbon and then a decrease in the atmospheric carbon. Students will print out the graphs and write out on the graphs how these changes have affected their biome. 

Day 5: Students share their presentations with another group, working on the same biome, discussing their findings. Next, students choose one of the presentations to be shared with the whole group to represent their biome.  Adjustments to the presentation are made as needed after the biome groups have had an opportunity to give input.

Day 6:  Chosen presentations are shared with the class during the first half of the class period.  After the presentations are completed, the teacher leads a wrap-up discussion emphasizing important points and student findings.

Day 7: An essay test is administered to check the students' level of understanding of how the carbon cycle helps atmospheric scientists understand and prepare for global climate changes.