Sustainability Lesson 1:
Tragedy of the Commons
<< This is a classical topic from sustainability science. It is actually very easy to understand even for young children and can be included as part of English-Lessons at any level.
The classic example is:
A group of 10 fishermen are living around the same lake. In the lake, there are fish and they reproduce at a rate of, let’s say 5% per month.
The underlying problem is that the amount of fish-increase is proportional to the number of fish already living in the lake. This is true for most ecosystems.
Let’s say we have an initial population of 10000 fish living in the lake.
Now each of our fishermen has to make a decision. He can either catch is fair share of the increase, which is calculated as 10000 * 5% /10 = 50 fish per month, or catch some more.
As long as every fisherman catches his 50 fish, the population will stay constant and there will be enough food for everybody, but no profit of selling fish.
However, if one of the fishermen is selfish and catches 100 fish instead of 50, next month there will only be 9950 fish left, and the “fair share” decreases to 9950 * 5% /10 = 49.75 Fish.
If everybody continues as before then next month there will only be only 9896 fish left.
After a while, the fish population depletes down to a level where nobody has enough food.
This is only an example - you can use different numbers, or a different example depending what kind of kids you’re teachings. Choose something which relates to their lives, be it trees in the forest or kg of grass on the pasture:- whatever natural resource they know from their everyday life.
This principle can be nicely demonstrated when you implement a game over several lessons. Take into class a box of 1000 pieces of candy and add 5% each lesson. The kids give you (secretly) a piece of paper demanding how much candy they want, and receive their candy in a closed paper, so nobody knows how much they ask for.
After a few lessons, you can give them extra options, like allowing them to add “governance rules”. For example, someone plays the policeman:- he doesn’t get any candy directly, but if there is a policeman, those who take more than their fair share don’t get anything as well because the policeman stops them.
Maybe your kids are smart enough to “pay” someone to be the policemen?
Or they come up with something completely different?
Or they agree to let the pot grow for a few lessons in order to increase the amount of the fair share afterwards?
Or they use up the resource till nothing is left?
You can choose any bonus - maybe candy is not the best as it is bad for their teeth. Just make sure that they actually get out more when they use it sustainabley. If you are there only for a limited time, it might pay off better for them to exploit you :-)
This exercise can nicely be combined with theoretical lessons about the adult world surrounding them. Pretty much in anywhere in the world there are some mismanaged natural resources, so try to pinpoint those to the kids. For more information and a deeper understanding look online at something like wikipedia, searching for “Tragedy of the commons”.