• Views 37
  • Favorites
Photo by Denisse Leon via Unsplash


Expressions and Equations


6th, 7th, 8th




60 minutes

Regional Focus



Google Docs, Google Slides


This lesson plan is licensed under Creative Commons.

Creative Commons License

Comparing Biofuels (Renewable Energy Algebra #4)

Created By Teacher:
Last Updated:
Dec 9, 2022

In this lesson, students are introduced to biomass energy and use algebra to calculate the amount of land needed to produce biofuel using different plants.


Step 1 - Inquire: Students watch a video on biofuels and discuss how biofuels are similar to or different from other renewable energy sources.


Step 2 - Investigate: Students complete real-world math problems that compare the amount of land needed for various biofuel crops.


Step 3 - Inspire: Students explore the current use of biomass in their region using this map and discuss potential benefits and drawbacks to increasing biomass energy in their community.


  • Students have opportunities to think critically about the topic of renewable energy in their community.

  • Students have the chance to use math in a real-world application, which makes it more relevant and engaging.

Additional Prerequisites

  • This is lesson 4 of 5 in our 6th-8th grade Renewable Energy Algebra unit.

  • This lesson could be used as a standalone lesson if desired.

  • There are quite a few drawbacks and challenges to large-scale biofuel production and use. Students should begin to see this through their calculations and discussion. An optional extension video is included at the end of the lesson that looks more at some of the issues with biofuel.


  • Teachers can have students work with a partner on the calculations in the Investigate section and purposefully group students based on skill level.

  • Teachers can work in a small group with students who may need additional assistance with the calculations.

  • Teachers can limit the number of questions students complete. Questions get progressively more difficult on the Student Document.

  • Interdisciplinary connections can be made with Earth science, physical science, and engineering design.

This lesson introduces students to biofuels and how they are sourced, including the supply chain. It does not only equip them to compute the acres of land needed to grow crops to produce biofuels but allows them to compare biofuels with other renewable energy sources, including the benefits and limitation to scale up. All the materials have been fact-checked, and they are suitable to build students' knowledge on the topic. Hence, this lesson has passed our science credibility process.

This resource addresses the listed standards. To fully meet standards, search for more related resources.

  • Common Core Math Standards (CCSS.MATH)
    • Ratios & Proportional Relationships (6-7)
      • CCSS.MATH.CONTENT.6.RP.A.3 Use ratio and rate reasoning to solve real-world and mathematical problems, e.g., by reasoning about tables of equivalent ratios, tape diagrams, double number line diagrams, or equations.
    • Expressions & Equations (6-8)
      • CCSS.MATH.CONTENT.6.EE.A.2 Write, read, and evaluate expressions in which letters stand for numbers.
      • CCSS.MATH.CONTENT.6.EE.B.6 Use variables to represent numbers and write expressions when solving a real-world or mathematical problem; understand that a variable can represent an unknown number, or, depending on the purpose at hand, any number in a specified set.
      • CCSS.MATH.CONTENT.7.EE.B.3 Solve multi-step real-life and mathematical problems posed with positive and negative rational numbers in any form (whole numbers, fractions, and decimals), using tools strategically. Apply properties of operations to calculate with numbers in any form; convert between forms as appropriate; and assess the reasonableness of answers using mental computation and estimation strategies. For example: If a woman making $25 an hour gets a 10% raise, she will make an additional 1/10 of her salary an hour, or $2.50, for a new salary of $27.50. If you want to place a towel bar 9 3/4 inches long in the center of a door that is 27 1/2 inches wide, you will need to place the bar about 9 inches from each edge; this estimate can be used as a check on the exact computation.
      • CCSS.MATH.CONTENT.7.EE.B.4 Use variables to represent quantities in a real-world or mathematical problem, and construct simple equations and inequalities to solve problems by reasoning about the quantities.

  • Students think-pair-share to answer the following questions:

    • What are some alternatives to gas-powered cars?

    • Have you heard of biofuel before? What do you know about it?

  • Students watch this video about biofuels.

  • Students share with a partner one new thing they learned about biofuels.

  • Students think-pair-share to answer the following questions:

    • How is biofuel similar to other renewable energy sources we have looked at?

    • How is biofuel different from other renewable energy sources we have looked at?

  • Teacher introduces the vocabulary words that will be necessary for the rest of the lesson.

  • Students complete the Student Document that guides them through calculations related to biofuels.

  • Students can work independently and then compare their work with a partner.

  • Teacher should check in after students complete the first question to make sure all students have the correct answer before moving on since the questions all build from the first answer.

  • Students explore the map showing biomass energy and infrastructure.

  • Students zoom into their region and identify the biomass resources available to their community.

  • Students discuss the following questions:

    • Does your community have access to biomass resources?

    • Why do you think your community does or does not have access to biomass resources?

    • What do you think are some benefits to using biomass energy?

    • What do you think are some drawbacks to using biomass energy?

    • Do you think your community should increase biomass energy use? Why or why not?

    • What might be some more efficient uses of the land instead of growing crops for biofuel?

    • Based on what you’ve learned in the last four lessons, how do you feel about renewable energy use?

  • Students complete a short 2-question exit ticket, which teachers can use to assess learning.

  • Students can watch this optional extension video that looks at issues with using biofuel at a large scale. Teachers can use the following discussion questions with the video:

    • What prevents biofuel from being a practical and widely used energy source?

    • How have innovations in biofuel helped bring us closer to large-scale use?

    • Do you think biofuels are still a promising climate change solution? Why?

Renewable Energy Algebra Unit Lesson Plans


Login to leave a review