For an environmental ethics course that I taught in 2017, I wanted a game to pair with Catriona McKinnon’s accessible paper, “Runaway Climate Change: A Justice-Based Case for Precautions” (Journal of Social Philosophy 40 [2009]: 187–203). The paper argues that justice requires precautionary approaches to climate change to avoid crossing catastrophic tipping points, such as the thawing of vast methane deposits in Arctic permafrost. Such threats of catastrophe are real, but they’re distant in almost every sense of the word. To get students to feel the need for precaution, I needed something that would bring the threat to them.

I called my game “Extra Credit Catastrophe.” In brief, it works like this: The students represent global society. Each one receives a bag of small candies—Skittles, in my class—representing their wealth. For each of eight rounds (representing the remaining decades of this century), each student must decide how much wealth to “spend” on “mitigating climate change.” I then roll a die to determine how much the planet will warm in that round, subtracting a larger or smaller amount depending on how much “global society” has spent. The class’s ultimate goal is to prevent warming from crossing an uncertain threshold—somewhere between 1.5ºC and 3.0ºC. If they succeed, everyone gets extra credit. If they surpass the threshold, catastrophe strikes and no one gets the extra credit. To complicate things, however, each student has another opportunity for extra credit: anyone who has at least ten candies at the end of the game gets some individual extra credit, giving each player a personal incentive not to mitigate.

In my own class, the game generated excellent and insightful class discussion, which covered not only the main point of McKinnon’s paper, but also a range of important issues in climate ethics, including distributive justice, procedural fairness, transparency, priority for the worst off, climate finance, and more.

You can download a complete description of the game below, either as a PDF or a Word document, along with a spreadsheet useful for preparing and playing the game. This material is released under a Creative Commons Attribution-NonCommercial 4.0 (CC-BY-NC 4.0) license, so you're free to modify and share it for any non-commercial purpose.


download game description in pdf

Click here to download a complete description of the Extra Credit Catastrophe game as PDF document.



Click here to download a complete description of the Extra Credit Catastrophe game as a Word document.



Click here to download an Excel spreadsheet to use in preparing for a playing the game in class.