NOW with Bill Moyers

Global Warming
Lesson Plan

This lesson is designed for social studies, debate, language arts, government/citizenship, and current events classes, grades 9-12.

Lesson Objectives

By the end of this lesson, students will:
  1. Form definitions of the greenhouse effect based on prior knowledge, class discussion, and viewing diagrams.
  2. Participate in group brainstorming sessions and class discussions related to the impact of the greenhouse effect and global warming.
  3. Analyze global warming diagrams and resources to obtain a clear understanding of this scientific process.
  4. Hypothesize about the effects of global warming on the climate and the world's populations.
  5. Conduct research using a variety of primary sources to explore perspectives in the global warming debate.
  6. Complete a Venn Diagram that compares various points of view on global warming issues.
  7. Take a position on global warming and support this viewpoint with reasons, facts, and examples gathered during lesson activities
  8. Create a project that supports their point of view about global warming issues.

Related National Health Standards

These standards are drawn from "Content Knowledge," a compilation of content standards and benchmarks for K-12 curriculum by McRel (Mid-continent Research for Education and Learning), at


Standard 8: Understands the characteristics of ecosystems on Earth's surface.

Standard 14: Understands how human actions modify the physical environment.

Standard 16: Understands the changes that occur in the meaning, use, and distribution and importance of resources.

Standard 18: Understands global development and environmental issues.

Standard 2: Knows environmental and external factors that affect individual and community health.
World History
Standard 44: Understands the search for community, stability, and peace in an interdependent world.
Language Arts
Writing, Standard 4: Gathers and uses information for research purposes.

Reading, Standard 7: Uses reading skills and strategies to understand and interpret a variety of informational texts.

Listening and Speaking
Standard 8: Uses listening and speaking strategies for different purposes.

Standard 9: Uses viewing skills and strategies to understand and interpret visual media.

Standard 10: Understands the characteristics and components of the media.

Thinking and Reasoning
Standard 1: Understands and applies the basic principles of presenting an argument.

Standard 2: Understands and applies the basic principles of logic and reasoning.

Standard 3: Effectively uses mental processes that are based on identifying similarities and differences.

Standard 6: Applies decision-making techniques.

Estimated Time to Complete Lesson

Four or five 50-minute class periods, plus some time outside of class to complete the final project. Some other in-class activities in this lesson plan could be completed for homework, if preferred.

Materials Needed

  • Internet access, or copies of relevant pages
  • Copy of the 4/22/05 NOW broadcast on global warming. (Note: A free transcript of this program is available on the NOW Web site. Teachers may also tape the broadcast off-air and use it in the classroom for one year. Alternatively, programs are available for purchase from ShopPBS (
  • TV/VCR
  • Handout: Global Warming Venn Diagram (PDF file)
  • Handout: Global Warming Project Ideas (PDF file)

Backgrounder for Teachers

Is human activity bringing about alarming global warming scenarios and related catastrophes? Or is such thinking a myth brought about by flawed or incomplete science? Finding the answers to these questions has turned global warming into a highly politicized and contentious issue.

Until about 1960, most scientists thought it implausible that humans could actually affect average global temperatures. (See NOW's History of Global Warming at Today, most scientists agree that earth's temperature has risen over the past century and that carbon dioxide is one of the primary greenhouse gases that contribute to global warming. Disagreement persists, however, over whether or not global climate change is a normal environmental variation, and over how big of a problem global warming could become for the planet. (See NOW's Climate Change Debate)

Amidst such controversy, world leaders have met and outlined legal rules, known as the Kyoto Protocol, to limit the emissions of greenhouse gases. One hundred forty countries that collectively represent 61.6% of greenhouse gas emissions worldwide have ratified the Kyoto Protocol. (See NOW's International Perspectives on Global Warming)

The United States does not support the Kyoto Protocol and disagrees with a number of its provisions. Instead, the U.S. is funding additional scientific research on the causes and effects of global warming, encouraging climate change technology research and development efforts (See NOW's Global Climate Change Technology Advancements), looking at how its own federal and state laws can regulate greenhouse gas emissions in the U.S. (See NOW's summaries of the Clear Skies Initiative at and California's Auto Emissions Laws at, backing the research and development of renewable energy sources, and pursuing other strategies that it believes will address global climate change without major upsets to the U.S. economy.

Assumed Student Prior Knowledge

Students should be familiar with the terms, "global warming," the "greenhouse effect," and "greenhouse gases." Also, that the U.S. is a leading producer of greenhouse gas emissions that contribute to global warming.

Teaching Strategy

Part 1: Reviewing the Facts: What is The Greenhouse Effect? (30 minutes)

1. Before class begins, post the term, "greenhouse effect" where students can see it.

2. To begin the class, ask students to think quietly, without talking, about a definition for the greenhouse effect. Give them a minute to formulate their ideas and then have them write down their definition so they can share it.

3. At the end of the allotted time, ask students to share their definitions with one or two other students sitting nearby and compare the similarities and differences in their definitions. Allow a few minutes for student pairs or groups to then combine their definitions into one that they believe is the most accurate.

4. Begin a class discussion by asking several pairs/groups to share their definitions of the greenhouse effect.

5. Next, show students a Flash animation (found at the U.S. Environmental Protection Agency's Web site: that accurately describes the greenhouse effect and how it likely contributes to global warming. You might have students take turns reading the dialogue balloons for the characters shown on the site. Alternatively, the EPA Web site also provides a simple diagram with text explanation of the greenhouse effect at: Ask students to make any corrections to their definitions based on what they've learned.

Part 2: Making Predictions About The Effects of Global Warming (20 minutes)

With an understanding of the greenhouse effect and global climate change, students can now make predictions about the potential impact of global warming.

1. Ask students to hypothesize about how the world's climate could change over the next 100 years if humans do nothing to limit the levels of their greenhouse gas emissions. Have them also make predictions about the effects such climate changes could have on humans.

2. Working in pairs, small groups, or as a class, students should brainstorm a list of their ideas related to these questions. Each student should record a copy of the list in order to refer back to it later in the lesson.

3. Next, refer to the Flash animation from Part I and a diagram from the Augusta Chronicle ( to find additional information on the causes of global warming and what the effects of this process could be.

Part 3: Comparing Points of View on Global Warming (90 minutes) 1. Pose the following question: In your opinion, has human activity caused the world's climate to change over the past 100 years?

2. Distribute copies of the Handout: Global Warming Venn Diagram (see Materials Needed) and review the directions for completing the diagram.

3. Using the resources listed here, have students work in pairs, small groups, or as a class to complete the graphic organizer, noting specific facts and using the back of the sheet to note more in-depth details as needed. Resources include:

Part 4: Forming Opinions About Global Warming (30 minutes)

Now that students have explored a variety of perspectives on global climate change, they will take a position on the issue and support it with data. 1. Ask students to write 2-3 persuasive paragraphs to answer the following questions:

  • In your opinion, is global warming an imminent world threat? Why or why not?
  • Based on your opinion, what actions do you believe should be taken to address the global warming issue? Remind students to support their opinions with specific information from the brainstorming lists created in Part 2 and their completed Venn Diagrams from Part 3.
2. Once students have organized their thinking on paper, give students the opportunity to share their opinions with at least one other student in class. Do not allow discussion or debate; rather, allow students to practice sharing what they have written so that others can hear the reasons behind their positions.

Part 5: Final Project (45 minutes, plus outside preparation time)

1. Invite students to choose a project from the Handout: Global Warming Project List (see Materials Needed). Alternatively, students could design a project of their own with teacher approval. The goal of the project is for students to create something substantive that they can use to share their positions on global warming and to increase awareness about its related issues.

2. Allow students one class period to begin work on their projects, then assign a completion date. When projects are completed, display student projects and/or have students present them to the class as a way of demonstrating their point of view on global warming issues.

Assessment Recommendations

Consider the following assessment ideas:

  1. Give students completion grades for participating in class discussions and filling in the Venn Diagram worksheet.
  2. Using a scoring guide or a peer-evaluation rubric, provide students with feedback about the effectiveness of their persuasive writing responses to the questions posed in Part 4 of the lesson.
  3. Using a scoring guide and a self-evaluation rubric, have the teacher and the student evaluate his/her project using criteria established prior to completion of the assignment.
  4. As students present their projects to one another, have their classmates complete a peer evaluation form that assesses the effectiveness of the project in terms of providing factual information to others.

Extension Ideas

1. For a good visual representation of the potential dangers of global warming, show students the interactive map from the Intergovernmental Panel on Climate Change (IPCC), located at: As a class, discuss what the various markers on the map indicate. View the map as a whole. Then, click on the U.S. and selected other regions to illustrate the widespread warning signs of global warming. Take time to go to the link focusing on New Points ( and discuss the number of additions made since the map was first constructed a few years ago.

2. Explore what could happen to U.S. relations with other countries if:

  • Adequate alternative energy sources were developed and we no longer relied on imported fossil fuels for power/fuel.
  • We fail to limit U.S. greenhouse gas emissions while other countries are actively regulating such emissions.

3. Discuss the effects of greenhouse gasses on the overall health of people worldwide. Address questions such as:

  • What types of illnesses/diseases can be attributed to greenhouse gas emissions?
  • How can changes in the world climate increase health risks for people worldwide?

Related Resources

CNN: The Science Debate Behind Climate Change
This 4/8/05 CNN story describes the contention among scientists regarding global climate change.

NEWSHOUR Extra: Global Warming Fears Lead to Ratification of the Kyoto Protocol
This 2/14/05 NEWSHOUR with Jim Lehrer Special for Students summarizes the problem of global warming, briefly outlines details of the Kyoto Protocol and world opinion, and describes the U.S. response.

United States Environmental Protection Agency: "Global Warming Quiz"
This online EPA resource provides five questions that check basic understanding of the causes of global warming.

What's Up With the Weather? This NOVA and FRONTLINE special report on global warming provides graphs, a helpful FAQ, an interactive activity that helps students recognize sources of daily energy consumption and determine their "diet" of carbon, perspectives for and against global warming, and more.

About the Author

Lisa Prososki is an independent educational consultant who taught middle school and high school English, social studies, reading, and technology courses for twelve years. Prososki has worked extensively with PBS authoring and editing many lesson plans for various PBS programs and PBS TeacherSource. In addition to conducting workshops for teachers at various state and national meetings, Prososki also works with many corporate clients creating training programs and materials, facilitating leadership and operations workshops, and providing instructional support for new program rollouts. Prososki has authored one book and also serves as an editor for other writers of instructional materials.