16 pebbles in a communal pile for each community.
the rules of the game:
pebble pile represents a valuable renewable resource. The resource
is replenished after each round of play.
community member may take freely from the resource pile each round.
community member must take at least one pebble in each round to survive.
in each community must record the number of pieces taken by each community
member in each round.
each round, count how many pebbles each community has remaining in the
pile, and add an equivalent number of pebbles to the pile.
or four rounds, pausing after each round to find out if any community
members did not survive.
final round, then have community members share what happened in their
communities did everyone survive?
community had the most pebbles in the resource pile at the end of
communities are confident they will always have enough pebbles for
everyone as long as the pile is renewed? How did these communities
arrive at that point? What strategies were used?
there a leader in these communities? If so, why did the community
listen to that person?
these communities have reached "pebble sustainability" without communication?
per capita pebble ownership around the room.
of the whole room, who had amassed the most pebbles? How did he or
she accomplish this?
this keep others from surviving?
do we see this type of greed in the real world?
a discussion of the following:
information is necessary to know how to manage a resource sustainably
(e.g., community size, resource renewal rate, environmental carrying
is needed to actually put information into practice (e.g., leadership,
communication, trust, legislation, understanding of consequences,
examples of failure, etc.)?
that all communities are taking pebbles from one communal pile. Some
communities are at war with one another, and some are unaware of the
the pebbles still need management? How would these factors affect
the management of the pebbles?
these situations change how community members felt about adhering
to their sustainable usage?
might global pebble usage be managed? Write suggestions on the chalkboard.
that this scenario represents the current state of our common resource,
the atmosphere. Automobile and factory carbon dioxide emissions are
heating up the atmosphere, causing the "greenhouse effect" and changing
the ecology of the planet. Each pebble taken represents one "share"
of carbon dioxide emissions generated by that person.
the communities that reached sustained usage feel about the "greedy"
the atmosphere be managed? Would the suggestions listed on the chalkboard
be useful in this situation?
other "real life" examples of shared resource issues?
represent a valuable renewable resource. In the United States, this game
is often played with individually wrapped candies. The participants are
told they can keep and eat the candies they have at the end of the game.
Using candies or coins rather than pebbles helps participants understand
the temptation and greed associated with this game and how it applies
to the real world. The authors realize that playing with food is not culturally
acceptable in many societies.
from "Greed vs. Need" in Project Learning Tree: Pre-K-8
Activity Guide, 3rd edition, American Forest Foundation, 1995,
and "Why EE?" in EE Toolbox - Workshop Resource Manual,
by J.F. Disinger and M.C. Monroe, Regents of the University of Michigan,