Picture a busy three-lane freeway, like the 110 that leads from downtown Los Angeles to Pasadena. Now picture one of the lanes coming to a complete and immediate stop. Cars crash. Metal and glass debris flies in all directions. If a student can describe the propagation of the wreck in physics and engineering terms, then they are ready for Brent Fultz's next lecture.
Fultz, the Barbara and Stanley R. Rawn, Jr., Professor of Materials Science and Applied Physics, has taught Caltech's Materials Science 132, Diffraction and Structure, for three decades. The course for first-year graduate students covers how waves relate to and interact with materials. It has long been one of Fultz's favorite classes. "I think it's rather elegant to work with waves and how they interact with solids," Fultz says. For his long-running course to thrive in a Zoom environment, he leaned on a few teaching strategies aimed at promoting connection and interactivity, including pre-class problems and thought experiments such as the freeway pileup.
"I think the biggest improvement I made in the class when I was doing live teaching was to force the students to work on something before they came into class, just so they got to thinking about it," he says. Fultz carried over the idea of pre-class questions this spring, when Caltech courses moved online because of the COVID-19 pandemic, by posting them to the Canvas site where Caltech faculty post their class materials.
The challenge became to maintain interactivity and interest during fully online lectures, something Fultz acknowledged in a letter to his incoming students for the fall term. "I would rather show up in room 104 Watson with chalk and laptop, and do a class with live questions from you," he wrote. "Some of this is lost by moving this course online."
The first approach he tried was to prerecord his lectures for students to watch together in real-time over Zoom. That way, he says, he could pause the talk every 10 minutes to solicit questions and make sure everyone in the class was on the same page. To his dismay, it didn't work especially well for the students or their instructor. Some of the students found that the prerecorded lecture moved through the material too quickly, and few in the class raised organic questions. Fultz found himself staring at a sea of faces and blank, black screens, unable to detect the kind of nonverbal cues that tell a teacher whether the class is engaged or bored. "What I needed was more in-class discussion and problem-solving," he says.
Undeterred, Fultz tweaked his approach. He decided to tell groups of three students before each 15-minute section of class that they would be responsible for asking questions during the following break, thereby ensuring they engaged with the material to prepare their question. Like the pre-class questions, this approach made students feel at ease talking about the material and stimulated conversation across the technological barriers of remote learning.
For his next challenge, he figured out how to replicate the kinds of informal communication that happen around the edges of an in-person class. On campus, Fultz would leave his office door open and loved when students swung by to talk through their diffraction work with him, but starting those conversations through formal tools, such as the Piazza messenger tool that is integrated into Canvas, has proven difficult. Fultz still mentors a group of undergraduates and discovered that they talk to one another about their courses via the messaging app Discord. "They have a pretty lively back-and-forth," he says. Now he is interested in finding similar ways to keep the conversation going after class with his graduate students.
And when in-person classes eventually resume? Fultz plans to use remote teaching strategies like asking students to be ready to ask a question. "I'm pretty enthusiastic about bringing that back to the live class," Fultz says.