Teaching Biophysical Chemistry
I have been learning how to teach Biophysical Chemistry (Chem 302) for the last six years. This course occupies a funny place in the Chemistry curriculum: it is taken by mid-career students with a penchant for understanding the molecular underpinnings of living systems, by precocious sophomores brimming with AP credits, and by a few curious BME and physics students.
Before I grabbed the course, it had been a mixed bag – some years focusing on biophysical methods (X-ray diffraction, NMR, CD, etc.), other years offering a sampling of current topics from the literature. I wanted to bend the course toward understanding how complex, useful function emerges from molecular structure.
There are plenty of textbooks with titles like Biophysical Chemistry or Physical Chemistry for Biologists. None is modern or conveys the dynamism of the field. Standard texts deliver diluted versions of thermodynamics and statistical mechanics, with a small admixture of geriatric biology. Fortunately, the last few years have seen an uptick in the publishing of ambitious new texts focused on the molecular and physical underpinnings of biological function. I began by experimenting with these texts in a traditional lecture style course, on my own and in collaboration with Glenn Edwards in Physics.
The student response to my vision was lukewarm. The mix of descriptive and quantitative material was disorienting. The textbook material was long and all over the map: some too physics-y, some too math-y. When a student casually said to me: “Prof. Beratan, the amount of reading in this course is insane!” I realized that I might need to reassess.
With help from Andrea Novicki, two amazing TAs (Julia Roberts Johnson and Ellie Zheng), and several undergrads who took pity on me (Mac Karnuta, Thu Nguyen, Kendall Bell, and Andy Chen), we rolled out and refined a flipped-style introduction to biophysical chemistry. The course tries to show how molecular structure, thermodynamics, kinetics, statistical mechanics and quantum mechanics can be put in service to understand the function of living nanomachines.
The key to our experiment has been to flip the course, install a team-based learning approach, and create 30+ screencasts (about one per class meeting) to guide the students through fundamental ideas and to liberate class time for group problem solving and discussion.
Elements of the Flipped Class Experiment
I explored the simple strategies for creating screencasts: Laptops running Screencast-O-Matic, and tablets (Samsung Galaxy tablet, Surface Pro 3, and iPad Pro) running Explain Everything. No approach is perfect, but the iPad Pro works very well, now that the Pencil device is available. My Surface Pro 3 (with limited memory) was very slow to create MP4 files.
The goal of teaching the molecular basis of function is well suited for a flipped classroom setting, as the molecular origins of function can be illustrated with well-chosen in-class activities. Many “aha” moments are accessible with in-class activities. Junior chemistry majors are thrilled to work with their classmates, although some students imitate noble gas atoms in this setting. The most functional groups nucleated effective study groups outside of class, while others foundered (especially when students were chronically absent from class). I don’t understand exactly what the magic is in the high-functioning groups, or how to spread this dynamics across the entire classroom. It’s clear that the more “kinetic” demonstrations work the best – a favorite activity was to express Brownian ratcheting with a combination of coin flipping and stepping left to right across the classroom. There are many pitfalls. Some in-class activities don’t offer a payoff worthy of the time investment. Student explorations are less “linear” than a lecture, it’s difficult to predict how long it will take to reach the intended points of discovery and understanding.
Maybe because the content is focused and can be watched during a bus ride, students are drawn very strongly to the screencasts. Watching, pausing, reviewing, watching at double or half speed seems to suit learning. Deploying screencasts does demote the textbook reading to second tier status for many students, and this makes me a bit sad.
We have sharply defined learning objectives for each class day. While I understand and value the utility of these “contracts with the students,” I may have hit a point of learning objective saturation.
Flipped classes have many more moving parts than traditional lecture style classes. We are heavy users of Sakai to organize content. In particular, the Lesson tab was used to organize the readings, screencasts, homeworks, and in-class activities for each and every class meeting. We posted solutions with appropriate reveal dates.
Readings in a Rapidly Evolving Discipline
Our readings include textbook chapters (scanned and posted to Sakai from Phillips, Dill, Kuriyan, Hoffmann, Leake, Bialek, Grosberg, Hill, Oster, Golbeck, Gray), literature papers (Xie, Hopfield, El-Naggar), and postings from the Nobel Prize web site. The absence of a single textbook makes the class challenging for the teacher and the student. Students who pursue science as a profession will find that the textbook is not yet written on their thesis topic (whether graduate or undergraduate); the junior year is a great time to come to terms with learning at the frontiers of knowledge.
These efforts were supported generously by the Duke Learning Innovation (formerly CIT), the Department of Chemistry, the A&S Signature Course initiative, and by the Vice-Provost for Academic Affairs. Most of all, I thank my patient students, especially those who see the value in experiments like this and kindly offer time from their uber-busy days to provide thoughtful insights, and even to volunteer, from time to time, to help repair some of its wonkier content.
These are never what we hope they will be! There is clearly more work to do. But, as the father of a famous scientist once said, “What do you care what other people think?”