Find the Feedback Loop

This activity can be used in any course in which the content includes at least one feedback loop. It can has been tested with undergraduates but could be adapted for high school or masters level students as well.

• Students should have had an introduction to feedback loops.
• Students should have had some experience looking at and making sense of diagrams of feedback loops.
• Students must have literacy skills sufficient to independently read articles on earth and environmental topics at the level of a newspaper or popular magazine. 
• Students should have a basic understanding of the aspect of the Earth system that is the focus of the reading passage. BUT, importantly, they should not have been explicitly taught about the feedback loop they are supposed to be finding in the assigned article.

This activity can be used as either a learning activity or as an assessment.
(1) If used with younger students or as an in-class activity with limited time available, we recommend that you edit the article down to a few paragraphs so that the feedback loop can be found more quickly and easily.
(2) If used with more advanced students or as a take-home activity with more time available, you can provide the full as-published article. This format more nearly resembles the real-world challenge of spotting feedback loops in the wild. 
(3) If used as a culminating activity/assessment (after using format 1 or 2 during the semester), you can require students to find their own article in the popular media and complete the activity from there.

• Students should develop heightened awareness of the prevalence of feedback loops in the world outside of the classroom, and begin to develop the habit of mind of discerning feedback loops in their personal and professional lives.
•  Students should be able to recognize the likely presence of a feedback loop in a description of a phenomenon that is underlain by such a loop, even when the term "feedback loop" is not used.
• Students should be able to unravel the sequence of causal links that creates the positive or negative feedback loop, and depict those relationships graphically in a causal loop diagram.
•  Students should be able to explain clearly and completely how the diagrammed causal relationships combine to create the net effect/outcome of the loop taken as a whole, and how the net effect/outcome of the loop impacts the larger system within which the loop is embedded.

• Text analysis: Students will be reading moderately complex text about an earth or environmental topic, and analyzing the text for significant underlying patterns and processes that are not explicitly named by the journalist or writer.
• Analogical reasoning: Students will need to recognize that an observed phenomenon in the real world as depicted in natural language aligns with what they know about feedback loops.  Making such an alignment calls for analogical reasoning. They can make their analogical mapping in either of two ways: (1) between the situation described in the reading and another situation that they already know to be controlled by a feedback loop, or (2) between the situation described in the reading and a conceptual schema for how feedback loops work. The initial alignment may be fairly fuzzy, intuitive, and tentative; it will become more concrete and accurate as the activity progresses.
• Causal reasoning: Students have to pull apart the phenomena described in the reading and reconceptualize them into constructs that behave as variables (capable of increasing or decreasing) which will become the nodes of the CLD model, and causal relationships between these constructs which will become the arrows of the CLD model. To do this, they need to combine their understanding of Earth and environmental processes and the information in the reading to understand when a change in one node is likely to cause a change in another node.
• Diagrammatic model construction: Students then need to arrange these constructs and relationships into a positive or negative feedback loop model, such that the net effect of the diagrammed loop will result in an outcome consistent with the observed world as described in the reading. 
• Scientific writing: Students will need to write a coherent methodical narrative, linking empirical observations from the reading with interpreted causal processes.

• Working in groups: In some of our test classes/workshops, the first or first few attempts at this activity are done in groups, which has proven to be very effective.
• Oral presentation: In some of our test classes, an individual or small group representative explains to the larger group how their causal loop diagrammatic model works and how it could account for important aspects of the phenomena described in the reading. 
• English language fluency for geoscience: Analyzing and describing feedback loops makes use of some advanced linguistic features, notably use of the conditional mood to express a hypothetical or uncertain situation that is dependent on a certain condition or circumstance.  Mastering this use of language prepares students to write about processes on hypothetical past or future Earths which have conditions that differ from the present. 

Students read an instructor-provided article from the popular media that is relevant to the course content, and that describes a system with at least one feedback loop – but that doesn't use the term "feedback loop." Students find the feedback loop description and mark it. Then they construct a type of conceptual visual model called a causal loop diagram (CLD) that depicts the working of the feedback loop in the article. We provide a video on how to make CLD's. Finally, they write a narrative that describes how the feedback loop works and the impact of the loop on the large system within which the loop is embedded. Rubrics are provided for scoring student products.
Find the Loop reading passages (Microsoft Word 2007 (.docx) 18kB Jan3 25)

Answers to 4 provided reading passages (Microsoft Word 2007 (.docx) 444kB Jan3 25)

Student prompt for Find-the-Loop activity (Microsoft Word 2007 (.docx) 16kB Jan3 25)

Checklist for CLD and narrative (Microsoft Word 2007 (.docx) 14kB Jan3 25)

Detailed rubric for CLD and narrative (Acrobat (PDF) 140kB Jan3 25)

ppt on making CLDs_19feb2024.pptx (PowerPoint 2007 (.pptx) 8.3MB Jan13 25)

HowToMakeCLDs video_19feb2024.mp4 (MP4 Video 46.1MB Jan13 25)

• Choosing an appropriate reading passage is key to making this activity powerful for your class. We provide 4 possibilities from different domains of geoscience, but encourage you to find your own. The reading should include a description of a feedback loop that has a strong impact in a system that is important to your course content. It should be at an appropriate reading level for your students; you can tailor the difficulty level by providing an edited-down extract rather than the original article.
• We recommend explicitly telling your student that this activity is designed to foster a life-long skill: finding feedback loops in the world when they have not been explicitly pointed out by a teacher or other authority. 
•  One teaching sequence that has been found effective is to repeat variants of this activity three times: (1) based on short reading passage, teacher makes CLD on the board drawing on spoken suggestions from class; then instructor speaks the narrative aloud, modeling stepwise progression around the loop from initial nudge, (2) small in-class groups analyze a short reading passage, make CLD and narrative together using provided check-list to improve work as they go, (3) students work individually to do analysis of a longer reading passage, make CLD and write narrative, for credit, potentially as homework.
• For making CLDs, we recommend pencil and paper for individuals, as there is no technology learning curve and these tools will be available throughout life. For small group work, pencil and paper is also good, or collaborative-sized (approx 2x2feet) white boards. Best of all for small group work is collaborative-sized whiteboard plus 2"x2" sticky nodes; students write nodes on stickies, move them around until they find a sequence that works, and then fill in arrows and annotations with markers. If your course will later go on to teach computational systems dynamics, you can also have students make their CLDs in Vensim or STELLA -- but it's not worth the learning curve time unless they will use the software later in the course. 
• A variant of this activity has been used for online courses; students make their CLDs on paper as usual, photograph them with their cell phones, and submit photo. 
• You may be tempted to skip the narrative-writing requirement. We advise against this. We have found that students often go back and improve the CLD in the course of trying to articulate their reasoning as to why or how a change in one node will cause a change in the downstream node; this is an example of the self-explanation effect. Often, they are interested to notice that the journalist skipped over a step or two, which the students need to fill in from their knowledge of the Earth system. From an assessment perspective, it can be very difficult to judge how well an emerging learner actually understands the system from a CLD alone; CLD plus narrative is a far more informative student product. 
• The final step, concerning the impact or net effect of the loop as a whole on the broader system, is easy to overlook. And yet this is the entire reason why teaching about feedback loops is important -- because the loop as a whole changes the broader system in powerful and sometimes unexpected ways, far beyond the impact of any single link in the loop. If students are mystified about what is being asked for, it may help to give them an example. For instance, the net effect of the feedback loops that govern shivering and sweating is to ensure that the human body (the larger system) remains within the range of temperatures where the biochemical processes that maintain life can function optimally.

We offer two assessment approaches for this activity.
(1) A simple ten-item checklist that allows either student or instructor to check for completeness of the causal loop diagram and accompanying narrative. This is usually the preferred approach for instructional use. 
(2) A much more detailed rubric, that digs into students' understanding of relationships within the model and between the model and the Earth, and detects evidence of partial or emerging understanding.  This is usually the preferred approach for  SoTL (scholarship of teaching and learning (SoTL) or DBER (discipline-based education research).

Kastens, K. A., Shipley, T. F., & Wakeland, W. (2024). Developing and field-testing a rubric for evaluating students' causal loop diagrams. Paper presented at the International Systems Dynamics Conference, Bergen, Norway, available at https://proceedings.systemdynamics.org/2024/papers/P1354.pdf The parts of this paper relevant to classroom instructors cover:
* learning goals related to feedback loops;
* why it is hard and important to be able to recognize loops that have not been explicitly pointed out;
* why causal loop diagrams are a powerful way to organize one's thinking about feedback loops; 
* why an accompanying narrative is valuable for both improving students' own understanding and for revealing students' understanding to the instructor.