This activity was selected for the On the Cutting Edge Reviewed Teaching Collection
This activity has received positive reviews in a peer review process involving five review categories. The five categories included in the process are
- Scientific Accuracy
- Alignment of Learning Goals, Activities, and Assessments
- Pedagogic Effectiveness
- Robustness (usability and dependability of all components)
- Completeness of the ActivitySheet web page
For more information about the peer review process itself, please see http://serc.carleton.edu/NAGTWorkshops/review.html.
This page first made public: Apr 16, 2010
Skills and concepts that students must have mastered
How the activity is situated in the course
Content/concepts goals for this activity
- Students will research and apply knowledge of commonly depicted cycles of matter in Earth systems;
- Students will describe and make generalizations on the rates of processing of material within these same cycles;
- Students will identify and describe dynamic relationships between matter cycles;
- Students will evaluate the magnitude of impact of changes or disruptions of these dynamic relationships;
- Students will formulate hypotheses on the patterns of future interactions between matter cycles, based on altered levels of interconnectiveness.
Higher order thinking skills goals for this activity
Other skills goals for this activity
Description of the activity/assignment
The next element of this activity attempts to capture elements of complex Earth systems, especially the concepts of equilibrium, hysteresis, power law relationships, and sensitive dependence. All lines connecting the cycles are held taut, representing an equilibrium condition. Small shifts in one cycle are compensated for by consequent shifts in other cycles. Selecting one of the interconnecting strands, tension is in introduced, first in small pulls which accumulate to imbalance and shift the cycles slightly. A single large pull in one strand, to the point of breaking the yarn, causes some lines to slacken, perhaps to the point that they cannot be easily restored to tautness without dramatic shifts in the connected cycles. Re-tightening the connections causes a shift in the cycles, which takes place quickly and assumes a slightly different but at least familiar pattern. Having students then share their observations of the process of pattern description-imbalances-shifts-new equilibrium allows them to recognize the dynamic nature of Earth systems interactions as well as to seek deeper understanding of hidden elements within the Earth system.
- At least four posters depicting detailed graphical representations of matter cycles, such as water, carbon, rock, nitrogen, sulfur, phosphorous, mounted on cardboard or another rigid material. Students should have available to them information on each cycle, depicting relative volumes of material in each cycle phase, residence times of the material in those phases, and the processes that drive changes from one phase to another;
- At least one ball of yarn, in a different color, for each poster;
- Note cards on which students will write a description of the individual processes used to link cycles;
- Paper clips to hang the note cards on these connective strands.
Determining whether students have met the goals
Download teaching materials and tips
Matter cycle diagrams: