Corn: Food or Fuel



Grade Level & Subject: Grades 9-12: Civics

Length: 2 – 3 class periods


After completing this lesson, students will be able to:

  • Explain how ethanol is produced
  • Describe the pros and cons of using corn as a fuel source
  • Explain the attitudes of various groups involved in the corn as food vs. corn as fuel debate

National Standards Addressed:[1]

This lesson addresses the following National Standards for Civics and Government from the Center for Civic Education:

What are the Roles of the Citizen in American Democracy?

  • How can citizens take part in civic life?
  • What are the rights of citizens?

This lesson addresses the following National Standards for History presented by The National Center for History in the Schools:

Materials Needed:

  • Stopwatch
  • Reproducible #1 – Where is Corn Hiding?
  • Reproducible #2 – Food vs. Fuel Debate Roles
  • Reproducible #3 – Corn: Food or Fuel Debate Rubric

Students will be assessed through the following activities:

  • Participation in class warm up and wrap up discussions
  • Participation in the class debate
  • Completion (and presentation if applicable) of letter to Member of Congress
  • Completion of Reproducible #3 – Food vs. Fuel Debate Rubric



Relevant Vocabulary:

  • Distill:to let fall, exude, or precipitate in drops or in a wet mist.[2]
  • Enzyme:Any of numerous complex proteins that are produced by living cells and catalyze specific biochemical reactions at body temperatures.[3]
  • Ethanol: A colorlessvolatile flammable liquid C2H5OH that is the intoxicating agentin liquors and is also used as a solventand in fuel.[4]
  • Glucoamylase:An enzyme that breaks the bonds near the ends of large carbohydrates (starches), releasing maltose and free glucose.[5]
  • Yeast:a yellowish surface froth or sediment that occurs especially in saccharine liquids (as fruit juices) in which it promotes alcoholic fermentation, consists largely of cells of a fungus (as the saccharomyces, Saccharomyces cerevisiae), and is used especially in the making of alcoholic liquors and as a leaven in baking.[6]

Background Information:

The search for a viable alternative to fossil fuels has been fraught with difficulty.  In the United States of America, society is so dependent on fossil fuels to run cars and factories that we lose sight of the amount of harmful byproducts that are pumped into the air every day. It is increasingly understood that finding an alternative way to run industry and transportation is of the utmost importance. Suggestions have been made and many of them, such as solar power, hydrogen power and ethanol, have been incorporated into transportation and industry on a small scale.  However, each of these sources has failed to gain widespread use because of the objections that erupt from a variety of special interest groups.  This issue is particularly evident in the case of ethanol.

Ethanol is a fuel made from plant products. It is considered a renewable energy source because it depends upon the growth of a plant which, at the most basic level, only needs sunlight, soil and water to grow.  Ethanol can be made from an enormous variety of plant life, usually feedstock, such as switch grass, cane sugar and sugar beet, among others.  In the United States, ethanol fuel is most often made from corn.  The corn is harvested, ground, and taken to a site where it can be chemically converted to ethanol alcohol by a process of heating and cooling.  Gasoline is then added to ethanol liquid to make a blend of either 10% ethanol (which can be used in any car made after 1980 to improve performance and slightly decrease the amount of greenhouse gases emitted from the burning of the gasoline) or a higher concentration such as 85% which can be used only in cars specially fitted to run on ethanol.[7]

Making ethanol from corn becomes a highly contested issue when you consider corn as a popular food crop as well as the basis for fuel. Corn is a staple of the American diet and channeling large amounts of this crop into fuel would affect a high percentage of the foods that we eat everyday. Global debates over corn as food versus corn as fuel have opened up over the past decade as the use of ethanol has grown and continues to do so. Domestically, people in support of using ethanol fuel say that it is an excellent fuel source because it burns cleaner than gasoline and would help reduce the U.S.’s dependence on foreign oil.  They are also optimistic that it will provide more domestic jobs because it will open up a new sustainable market to corn farmers. This type of fuel offers stability because, unlike fossil fuels, it will never run out as long as the sun shines and farmers can irrigate their fields.

On the other hand, opponents of this energy source say that as long as global hunger is such a significant issue, the United States should not divert food that could be used to feed the hungry to power our vehicles, and thus our consumerist lifestyle.  They also fear that the use of corn for fuel would drive up the price of corn for food, thus making it more difficult for lower and middle class Americans to afford to feed their families.  Others claim that ethanol would not really diminish our reliance on fossil fuels at all because it takes a lot of fossil fuels to produce and transport ethanol.

Many arguments exist on all sides of this issue. In June 2011, the Senate showed where it stood on this debate by voting down a measure that would have eliminated federal subsidies for ethanol made from corn, but Capitol Hill has not heard the last of ethanol.[8] It is clear that this debate will not be settled easily. This lesson will help students examine the facts behind this issue and understand that there is no right or wrong answer. Students will be guided towards forming an intelligent opinion, but will realize that this is a very complex issue that will not be solved over night.




Warm-up: What can Corn do?

  1. Begin this lesson by passing out Reproducible #1 – Where is Corn Hiding?  Allow students five minutes to mark which items on the list they think contain corn or corn products.
  2. After everyone has finished, tell the class that in fact every item on the list contains corn in a variety of different forms (high fructose corn syrup, corn meal, corn starch, etc.).  Lead a discussion about the activity.  Which items were the students surprised contained corn? Answers will vary.  Why do they think that corn is such an important crop in the lives of Americans? Subsidies, lots of land well suited to grow it, is extremely versatile and can be used to support many other industries such as growing livestock, etc.  
  3. Ask students if they think using corn in the majority of the foods the American public eats is a bad thing.  Why or why not?  It is not very healthy, makes the country wholly reliant on a single crop, makes junk food cheaper than healthy food because of corn subsidies, etc.
  4. Next, ask the class what they know about ethanol as an alternative fuel source.  Make a list on the board of facts the students come up with.  Once students have answered, fill in the gaps by explaining that ethanol is a liquid fuel that can be made from a variety of plant sources such as corn, sugar cane, switch grass and many others. Explain that ethanol is considered a renewable energy source because it relies on plant matter which needs only soil, sun and water to grow.  In the United States, ethanol is usually made from corn; the very same corn that was used to make all of the items on the list.
  5. Present the first three minutes of the video “How Ethanol is Made”[9] by the American Coalition for Ethanol.
  6. Allow time for questions about the video. 
  7. Explain that the issue of using corn for food versus corn for fuel is a much contested question in American politics and that there are many arguments in the debate.  Ask students what their initial thoughts are about using corn for fuel versus corn for food.  Do they think one use is more important than the other? 

Activity One: Food vs. Fuel Debate

  1. Now that students have a basic understanding of what ethanol is and why its use is a difficult and multi-faceted issue, they have the right tools to begin to delve deeper into the debate.   Inform students that the following day they will all be participating in a class debate about the issue of using corn as a food or fuel source.  However, they will not be playing themselves, but rather one of a group of societal actors to whom this issue is very important.
  2. Ask students what types of groups they think have a vested interest in the ethanol debate and why. Keep a list on the board of all suggestions. Once students are stumped, add any missing actors from the list below and explain what their interest is in this debate. 
  3. Next, tell students that they will be each assigned to play one of these characters in the debate. They will have to figure out the point of view their character would take on this matter and why. They will also need to do research so they can support their claims accurately. A breakdown of the characters is below; the teacher may also add characters that students brainstormed previously.
  4. Assign each student a role to play in the debate.  The roles are as follows:
  5. Members of Congress (3-5  students)
  6. Government Officials (1-3 students)
  7. Small corn farm owner (1-3 students)
  8. Large agriculture industry supported farmer (1-3 students)
  9. Agriculture industry spokesperson (1-3 students)
  10. Pig farmer (1-3 students)
  11. Scientist (1-3 students)
  12. Middle class American parent (1-3 students)
  13. World Hunger Activist (1-3 students)
  14. Environmentalist (1-3 students)

Depending on the size of the class, each role may have a different number of students as listed above but make sure each role has at least one student. If the class is very small, the teacher can play the role of Congress to ensure that there are enough students to fill all the other roles. 

  1. Give each student a copy of Reproducible #2 – Food vs. Fuel Debate Roles to help them begin an investigation into their characters. 
  2. Tell the students that for the remainder of the class period and for homework that evening they must prepare to play their assigned roles in the debate the following day.  Tell them that “Congress” is currently debating a piece of legislation that would outlaw using corn to make ethanol. Congress has requested the presence of each character to help make the decision leading up to a vote at the end of the day.  Students assigned the same character will have to work together to develop a cohesive argument and each group will be given five minutes to explain their position before Congress. After a single student or group of students presents their argument, Members of Congress will have one minute to ask the questions they prepared beforehand. Tell students that the objective of the debate it to convince Congress to vote in their favor. Students should be as persuasive as possible by using important facts and information. Encourage students to play their parts as though they were real people (including real-life examples, props and costumes).  Remind students that if they are in a group of two or more students, they should distribute the work equally and each student should have a turn to speak during the presentation.
  3. Give each student a copy of Reproducible #3 – Corn: Food or Fuel Debate Rubric to outline all of the requirements for the lesson. Explain that they will have to turn the rubric in at the end of the activity with the self-assessment column filled in.
  4. Allow students the remainder of the class to begin research with books and Internet sources including those suggested on Reproducible #2 – Food vs. Fuel Debate Roles. Students playing actors should research their particular character’s position, while students playing Members of Congress should brainstorm pertinent questions to ask each actor after their presentation.
  5. Next class period, arrange the classroom so that the Members of Congress are sitting at the front and there is a space for characters to speak to Congress and the rest of the class. 
  6. Introduce the debate by reminding students that Congress is due to vote on a bill that would outlaw using corn to make ethanol.  Congress has asked many different groups to explain their position on this issue.  At the end of the debate, Congress will use the information it learns from each group to make its final decision.  Each group has five minutes to speak and must answer Congress’s questions for one minute afterwards.
  7. Use a stopwatch to accurately time each presentation and question session directly following. Allow five minutes for each presentation and one minute for questions from the Members of Congress. Depending on the length of the class, presentations might extend into the next day.
  8. After each character has presented, tell the class that now that Congress has listened to all the evidence, it is time for them make their final decision. Allow Congress five minutes to discuss their decision among themselves.  After a conclusion has been drawn, Congress should make a short presentation to the class stating its decision and briefly why it was chosen.
  9. For homework, students should write a short letter (2-3 pages) to their real Member of Congress about where the student personally stands on this issue.  The letter should be in a formal letter format, and include scholarly information with proper citations. Remind students that this letter does not necessarily have to reflect the viewpoint of their assigned actor, but rather their personal ideas after listening to each presentation in the class Congress session. Explain that letters to a real Member of Congress really can have a big effect on that Member’s political decisions and thus the letter should be taken seriously and executed professionally.  After all students have turned in their letters, send them to the local Member of Congress.   
  10. *Optional: Have students present their letters for the class on the day they are due.
  11. Have students fill out the self assessment portion of Reproducible #3 – Corn: Food or Fuel Debate Rubric and hand in along with their letters.  

Wrap Up: Review the Pros and Cons

  1. Make a class list of the pros and cons of using corn as a fuel source.  Allow students to contribute as many ideas as possible. Keep a list of all ideas on the board. Pros include cleaner and more sustainable than fossil fuels, larger market for corn farmers, renewable, etc.  Cons include creates higher food prices, uses fossil fuels in production and transportation, creates less energy than normal gasoline, etc.
  2. Next, ask the class to make a list of the pros and cons of using corn as a food source.  Keep a list of all ideas on the board.  Pros include easy and cheap to grow, plentiful amount of land on which to farm it, can be used in a large variety of products, is a native species, etc.  Cons include its use as a variety of unhealthy sweeteners (such as high fructose corn syrup), extreme dependence on a single crop, etc.
  3. Ask students if they think it is possible to ever settle this debate in a fashion that would satisfy everyone?  Why?  Do they have any ideas for a compromise that could allow corn to be used as both food and fuel in an equitable way?

Extension: Are There Other Options?

  1. Have students research other forms of alternative energy (such as hydrogen, solar, etc.) and compare and contrast it with ethanol.  Which is a more viable option?  Why?
  2. Assign students to keep a journal of the food they eat for three days.  After they eat each item, have them check the ingredient list to see if corn or a corn product is included.  Give them a list of tricky ingredient names that are likely to mean the item contains corn (such as hominy, masa, maltodextrins, sorbitol, vinegar, dextrose, food starch, vegetable starch, baking powder, maize, dextrin, vegetable gum, modified gum starch, and vegetable protein.)  How much of what they eat is made from corn?  Does this change their opinion on the debate?
  3. Research and create a presentation on a city that uses an alternative energy source to power some part of its infrastructure (such as a public transportation system).  Suggested cities include Rio de Janeiro, Brazil; one of the solar cities in Australia; etc.  What part of these systems has been successful?  What, if any, problems have arisen?  How could the system be improved?  Does it seem possible to create a similar system in the United States?



In this lesson, students examined the process of turning corn into ethanol fuel. They also explored the contentious issue of the food vs. fuel debate. By researching this topic, students took part in a current political issue to help deepen their knowledge of government.  Students critically analyzed this issue to develop strong and persuasive arguments that were presented to their peers. By the end of this lesson, students were encouraged to draw their own conclusions about this issue and present them in a letter of opinion to their Congressperson to engage their civic responsibility.



Annie Stoller-Patterson – Author

            Education Intern, Earth Day Network

Maggie Ollove – Editor

            Education Associate, Earth Day Network

[2]“Distill Entry.” Merriam-Webster Online Dictionary.Retrieved June 13, 2011 from

[3]“Enzyme Entry.” Merriam-Webster Online Dictionary.Retrieved June 13, 2011 from

[4]“Ethanol Entry.”  Merriam-Webster Online Dictionary. Retrieved June 13, 2011 from

[5]“Glucoamylase Entry.”  The Enzyme Experts.  Retrieved June 13, 2011 from

[6]“Yeast Entry.”  Merriam-Webster Online Dictionary. Retrieved June 13, 2011 from

[7] “How Ethanol is Made.”  Ethanol Promotion and Information Council, Inc.  Retrieved June 14, 2011 from

[8] “United States Senate Votes Down Ethanol Subsidies.”  Humanitarian News.  Retrieved June 18, 2011 from

[9]“How Ethanol is Made.”  Ethanol Promotion and Information Council, Inc.  Retrieved June 14, 2011 from