Coral reef

Photo: NOAA Photo Library

What is ocean acidification, and who is affected by it? In this ocean acidification mock conference, your students will practice arguing a stance on the issue from a particular stakeholder's perspective.


Through this lesson, students will:

  1. Learn what organisms are affected by ocean acidification
  2. Take on the role of one of the stakeholders affected by ocean acidification
  3. Create poster(s) to address their issue(s)
  4. Participate in a mock conference to address the affects of ocean acidification
  5. Discuss solutions to reduce ocean acidification
  • Stakeholder Cards (classroom set)
  • Conference Directions Sheet – 1 per group
  • Poster paper (one per group)
  • Markers, colored pencils, or crayons (set per group)
  • 6 envelopes with one blank paper taped to the outside and 5 blank papers inside
  • Scratch paper
  • calcifier: an organism that builds a calcium carbonate shell or skeleton
  • calcium carbonate: the basic material of which most marine shells and some skeletons are made
  • carbon dioxide: a chemical compound composed of two oxygen atoms bonded on either side of a carbon atom. While naturally occurring in our atmosphere, carbon dioxide is also the by-product of the combustion of fossil fuels, emitted from car engines, coal power plants, and other producers of exhaust. Carbon dioxide is a greenhouse gas.
  • green house gas: gases in the atmosphere that absorb and emit radiation within the thermal infrared range. This process is the fundamental cause of the greenhouse effect.
  • ocean acidification: the process by which carbon dioxide dissolves in seawater causing a decrease in pH. To learn more, see ‘Teacher Background.’


  1. Create six groups of students, one for each stakeholder group: Organisms, Fishing Industry, Energy Companies, Transportation Industry, Recreation/Travel Industry, and Representatives from the Public.
  2. Print out one set of Stakeholder Cards. Each group will get the card associated with their group. For example, the Fishing Industry will receive the “You are: Representatives of the Fishing Industry” card. *if groups are large, you may wish to print out more than one set so that students aren’t crowded around one card.
  3. Print out Conference Directions Sheet (one per group).
  4. We recommend breaking up the activities so that the first day focuses on preparing for the conference (introduction and creation of poster and presentations), reserving the second day for the actual conference, presentations, and class discussion.

Introduction: Day 1 (15 minutes)

How does ocean acidification affect marine life?

  • Explain to the students that the chemistry of the oceans is changing. Seawater is generally slightly basic, but due to human activity, the oceans are becoming slightly more acidic.
  • Ask students what it means for something to be acidic. You can get as in depth with your students as appropriate depending on their level of understanding of acid base chemistry. In the very least, discuss how acids often have a corrosive or dissolving effect.
  • Explain that while the oceans are becoming more acidic, they are only becoming slightly more acidic.
  • Ask students to Think-Pair-Share: What kinds of animals are in the ocean? Have students share their responses. As they share, write their responses on the board, but group them so that all of the organisms that are on one side are calcifiers (organisms that have a calcium carbonate shell or outer skeleton) and all of the other organisms are on the other side. *use the Organisms Stakeholder Card to brush up on your calcifiers!
  • After you have grouped the organisms, ask students to guess how you have grouped them (organisms directly affected by a more acidic ocean – calcifiers), and what characteristic they have in common (create calcium carbonate shells or external skeletons). Explain that as seawater becomes more acidic, the building blocks (carbonate) for these animals become less available. With an increasingly acidic ocean, these animals won’t be able to make their shells or grow.

What is causing the oceans to become more acidic?

  • Ask students for any guesses as to how the ocean is becoming more acidic (increase of carbon dioxide in the atmosphere primarily due to the burning of fossil fuels). Give them a few hints such as:
    • it has been increasing since the industrial revolution,
    • it is something humans are doing,
    • an airplane contributes to it when it flies,
    • drivers contribute to it when they drive,
    • depending on where they live (not all energy plants are coal-burning plants), when they turn on the light or their computer, they may also be contributing.
  • Explain that when the carbon dioxide dissolves in the water, this diffused CO2 undergoes a chemical reaction that forms carbonic acid, which lowers the pH of seawater in the process called ocean acidification. This acidification leads to a reduction of available carbonate ions that form calcium carbonate, the material many marine organisms use to create their shells and skeletons. Not only does acidification make it more difficult for these animals to make their shells, but it also can lead to the weakening or destruction of already formed shells

Who is affected by ocean acidification? Who affects ocean acidification?

  • Explain that they are going to become representatives from different groups that are either affected by ocean acidification in some way, or that contributes to ocean acidification in some way. They will take on the role of these ‘stakeholders’ and attend a mock conference aimed at trying to understand and solve the problem of ocean acidification.

Procedure: Day 1 (30 minutes)

  1. Divide students into their stakeholders groups and give each their Stakeholder Card.
  2. Give groups 20 minutes for small group discussion to prepare for the Mock Conference, knowing that they will be tasked with creating a poster that summarizes their stance.
    • Allow students some time to read their Stakeholder Card.
    • Remind them to take on the role of their stakeholder, even if that is not what they personally believe. Play up the role playing! Encourage them to have fun with their roles.
    • Facilitate discussions among groups and help them manage their time.
    • Have students create a draft of their poster on scratch paper.
  3. Now, give students 10 minutes to create the final poster for the Mock Conference.
    • Students must present their poster draft to a teacher before they can get poster paper and markers. This way you can monitor their progress and help them edit/revise their poster as needed. Encourage students to make their posters eye catching and easy to read.

Procedure: Day 2 (45 minutes)

  1. Give groups 5 minutes to practice their 1-2 minute presentation for the Conference.
  2. Spend 20 minutes on the Mock Conference Presentations: Six 1-2 minute presentations plus 1 minute for questions and transitions between groups.
  3. Mock Conference Discussion/Task Force Groups
    • ​Break groups up into Task Force groups which include at least one student from each stakeholder groups. Remind everyone that they will still be playing the roles of their stakeholder.
    • Give each Task Force an envelope prepared with one blank paper on the outside, and 5 on the inside.
    • Each Task Force will come up with the one biggest challenge they all agree upon and write this on the outside blank paper, sending their envelope down the line to other Task Forces. When receiving an envelope, Task Forces will now focus on finding solutions to the challenges, writing solutions on a blank paper inside and returning this to the envelope before passing it along. In this way, at the end of the activity, each Task Force has received solutions from every other Task Force that they will share to the whole group. For step-by-step instructions:
    1. Give each of the Task Forces an envelope and ask the question: What are the big issues or challenges surrounding ocean acidification? Also, give each group some scratch paper for brainstorming. You may need to adjust the number of pieces of scratch paper depending on the number of groups you have created. The number of pieces of paper is equal to one less than the number of groups you have, so if you have 6 groups you would give 5 pieces of paper.
    2. Brainstorm challenges or issues (3 minutes): Each Task Force will brainstorm on the back of their envelope their ideas for the answer to the question. They will then circle or rewrite what their group feels is the biggest issue or challenge. *The issue they have chosen must be clear and legible so that other groups reading it will understand.
    3. Pass envelope to neighboring group: For example, all pass to the group on their left, or whatever works for the physical layout of your classroom.
    4. Brainstorm solutions (2 minutes): Each Task Force now has a different envelope with another group’s ‘big issue’. On a piece of paper from the inside, brainstorm as many possible solutions to the ‘big issue’ as they can in 2 minutes.
    5. Continue rotations (2 minutes each): At the end of 2 minutes, place their paper into the envelope and pass envelope to neighboring group. Each envelope will pass through each group once and end at the original group. This way, at the end of rotations, each Task Force will end up with the envelope with their ‘big issue’ and 5 other groups’ papers with their solutions to that issue.
    6. Choose the best solutions (5 minutes): Each Task Force will have 5 minutes to review the solutions from the other groups and come up with their top 3 favorite solutions. To prepare to report back to the whole group, write each of the 3 solutions they picked on a piece of paper large enough to be able to see when posted on the wall or whiteboard. Students will report back during the Wrap-Up.

Wrap-Up Day 2 (15 minutes)

  • Bring the students back together and discuss with them their decision-making process.
  • Divide your whiteboard or wall space into the following categories: Research and Development, Government Involvement and Regulation, Individual Level, and Other. Have each group share their ‘big issue’ and each of the 3 top solutions with the class. Then ask them to place each of their issues into the appropriate category.
    • Research and Development: any solutions that involve studying something to learn more. For example, one might study the effects of increased acidity on coral populations. Or, one might spend money on researching alternative energy to reduce reliance on coal burning energy plants.
    • Government Involvement and Regulation: any solutions that involve regulation of companies or groups. For example, one might suggest limiting the amount of carbon dioxide emissions a company can create or else pay a fine.
    • Individual Level: these are solutions that individuals can make, such as buy more energy efficient vehicles or appliances, or turning off appliances when they are not in use.
    • Other: other suggestions that don’t fit into the above categories.
  • Were they any commonalities in their issues or in their solutions?
  • Highlight any of the solutions they came up with that are also currently being discussed in the real world. Refer to the Teacher Background section for a list of choices that are currently being discussed as of January, 2011.
  • Depending on the resources at your school, for the Conference Presentations, students can create a media-based presentation such as PowerPoint or video instead of a poster-based presentation.
  • You may choose to have the Stakeholder Groups do their own background research to supplement the information on their Stakeholder Cards.

Maibach, Roser-Renouf, Leiserowitz (2009). Global Warming’s Six Americas 2009: An Audience Segmentation Analysis

National Resources Defense Council. Ocean Acidification: The Other CO2 Problem

The Ocean in a High CO2 World Symposium, Summary for Policymakers 2009

NOAA PMEL Carbon Program

Acid Test: The Global Challenge of Ocean Acidification Film by the National Resources Defense Council, available online in its entirety

US Energy Information Administration Annual Energy Review August 19, 2010

Andiman, Martineau, Mink, Quiroz, The Other CO2 Problem: Chemical Reactions

Next Generation Science Standards

Disciplinary Core Ideas (MS and HS)

  • LS2.C: Ecosystem Dynamics, Functioning, and Resilience
  • ESS3.C: Human Impacts on Earth Systems
  • ESS3.D: Global Climate Change
  • ETS1.B: Developing Possible Solutions

Science and Engineering Practices (MS and HS)

  • Asking questions
  • Engaging in argument from evidence
  • Obtaining, evaluating, and communicating information
Appropriate for: 7th Grade - 12th Grade
Standards for: 7th Grade, 8th Grade, 9th Grade, 10th Grade, 11th Grade, 12th Grade
Prep Time: 5 minutes
Activity Time: 105 minutes
Subjects: Arguing from Evidence, Earth & Space Science, ELA Common Core