Thinking like a Chemist: Enculturation, Disciplinary Practice, and Problem-Solving
by Mercedes Taylor, Chemistry
Recipient of the Teagle Foundation Award for Excellence in Enhancing Student Learning, 2016
Related Teaching Effectiveness Award Essay: Overcoming Emotional Reactions to Chemical Reactions
Flanked by classmates busily shaking test tubes and recording notes, a student stares motionlessly at her own test tube, slumped in despair. This is a common scene in Chemistry 3AL: as in most laboratory courses, Chemistry 3AL experiments have a single desired outcome, be it the appearance of crystals or the disappearance of a liquid’s brown color. When faced with an undesired result, my students’ stress was clearly evident in their frantic attempts to change the outcome of their experiment, often followed by dejected inaction. Students seemed to feel that if their experiment did not go as expected, they were shut out of the learning process.
But if, as some learning researchers contend, learning is “a process of enculturation” (Brown et al. 1989), then creating an appropriate laboratory culture is crucial to students’ ability to learn a chemical theory or an experimental technique. When students’ experiments went wrong, I found that a particular series of teaching techniques prevented them from reacting emotionally, helped them learn the intended concept, and helped create an authentically scientific culture in which students could learn chemical theory or experimental technique even if an experiment yielded an unexpected result.
Because high stress levels associated with a certain learning task has an inverse relationship to performance, it is important to mitigate the students’ negative emotional reactions to what they perceive as an experimental failure (Kaufer 2011). The first technique I used was to use my tone and body language to convey positivity and curiosity. “Really? Cool! Nobody else’s reaction turned that color!” By engaging warmly with them, I lessened their frustration and incited their curiosity about the result.
Second, I questioned the students about what happened and why, and led them firmly towards a scientific explanation that reinforced the concept at hand. Especially in a laboratory context, inquiry-based learning (in which students “attempt to formulate theories to explain the phenomena they encounter”) is more important than the accumulation of correct facts (Winter et al 2001). If my series of questions was able to guide a student to use the relevant concept to explain their unexpected result, this led to an even better understanding of that concept than if their experiment had turned out as planned.
Finally, I used this conversation to teach the philosophy of science — that scientific progress relies on failed experiments and undesired results — and thus engaged the students in the “disciplinary practices” of chemistry (Metz 2011). To reinforce this message, I wrote “Interesting result” or “Good observations!” when grading their gloomy descriptions of unexpected data in their lab write-ups.
Grading students’ lab write-ups also allowed me to evaluate the success of my teaching strategy. With no intervention, a surprisingly high number of students wrote things like “Didn’t work, I don’t know why.” After using the teaching approach described above, a student was much more likely to write, “My test tube didn’t yield any crystals, probably because I used a lot of solvent,” thus describing the outcome in neutral terms and offering an explanation.
While the educational theories of enculturation and disciplinary practice explain the success of my techniques to help students learn the intended Chemistry 3AL concepts from undesired laboratory results, two other techniques would benefit my students: providing specific heuristics for chemical problem-solving, and fostering metacognition in the laboratory (Schoenfeld 1983; 1987; 2011).
A heuristic is a problem-solving strategy applicable to many situations, such as identifying the limiting reactant in a chemical reaction or listing possible sources of experimental error (Schoenfeld 2011). At the beginning of each lab period, I would provide students with a set of heuristics framed specifically for the challenges likely to be faced that day: if a given experiment were predicated on the physical separation of two liquids (like oil and water), I would lead a discussion on what questions students should ask themselves if they fail to see separation. What chemical concepts that the students know would prevent the liquids from separating? What laboratory techniques could be used to identify a liquid?
An indispensable part of these pre-lab discussions would be to encourage metacognition — a self-awareness in students of how they are approaching a problem (Schoenfeld 1983; 1987; 2011). When their experiment deviates from the procedure provided in the laboratory textbook, students should use metacognition to intentionally call upon the heuristics we’ve discussed, rather than adjust their experiment haphazardly.
Additionally, I would ask all students, even those who are satisfied with their results, to speculate in their write-up about how their experiment might have turned out differently. I would ask them to use the concept at hand to explain this alternative outcome and to describe what lab techniques they would use to test their explanation. This exercise would reinforce our heuristics and encourage metacognition in all students, not just those who were stumped by their unexpected data. Reading students’ speculations and metacognitive reflections would provide me with rich evidence of student learning, which in turn would enable improved assessment of the effectiveness of these teaching strategies.
Brown, John S.; Collins, Allan; Duguid, Paul. 1989. “Situated Cognition and the Culture of Learning.” Educational Researcher 18:32–42.
Kaufer, Daniela. 2011. “What can Neuroscience Research Teach Us about Teaching?” Presentation to How Students Learn Working Group, University of California, Berkeley, January 25, 2011. http://gsi.berkeley.edu/programs-services/hsl-project/hsl-speakers/kaufer/
Metz, Kathleen. 2011. “The Interplay of Conceptual Understanding and Engagement in Disciplinary Practices.” Presentation to How Students Learn Working Group, University of California, Berkeley, April 19, 2011. http://gsi.berkeley.edu/programs-services/hsl-project/hsl-speakers/metz/
Schoenfeld, Alan. 1983. “Beyond the Purely Cognitive: Belief Systems, Social Cognitions, and Metacognitions As Driving Forces in Intellectual Performance.” Cognitive Science 7:329–363.
Schoenfeld, Alan. 1987. Cognitive Science and Mathematic Education. New Jersey: Lawrence Erlbaum Associates.
Schoenfeld, Alan. 2011. “Learning to Think Mathematically (or Like a Scientist, or Like a Writer, or…).” Presentation to How Students Learn Working Group, University of California, Berkeley, April 19, 2011. http://gsi.berkeley.edu/programs-services/hsl-project/hsl-speakers/schoenfeld/
Winter, Dale; Lemons, Paula; Bookman, Jack; Hoese, William. 2001. “Novice Instructors and Sudent-Centered Instruction: Identifying and Addressing Obstacles to Learning in the College Science Laboratory.” Journal of Scholarship of Teaching and Learning 2:14–42.