Sources
The idea for this lesson came from Jen McGonigle, a science teacher from Haddonfield, New Jersey, who shared this activity during the Exploratorium’s Summer Teacher Institute.
Wikipedia has a wonderful summary of the tragedy of the commons. It includes an excellent review of Hardin’s original essay on the topic, historical background about where the concept of the commons originated, and many examples of modern commons problems: littering, air quality, water quality, population growth, logging, etc.
Standards
Grade 6
Ecology (Life Sciences)
5. Organisms in ecosystems exchange energy and nutrients among themselves and with the environment. As a basis for understanding this concept:
a. Students know energy entering ecosystems as sunlight is transferred by producers into chemical energy through photosynthesis and then from organism to organism through food webs.
b. Students know matter is transferred over time from one organism to others in the food web and between organisms and the physical environment.
e. Students know the number and types of organisms an ecosystem can support depends on the resources available and on abiotic factors, such as quantities of light and water, a range of temperatures, and soil composition.
Grade 6
Resources
6. Sources of energy and materials differ in amounts, distribution, usefulness, and the time required for their formation. As a basis for understanding this concept:
b. Students know different natural energy and material resources, including air, soil, rocks, minerals, petroleum, fresh water, wildlife, and forests, and know how to classify them as renewable or nonrenewable.
All Grades
Investigation and Experimentation
7. c. Construct appropriate graphs from data and develop qualitative statements about the relationships between variables.
