Molecular Biology professors find creative ways to teach during pandemic

Department Announcement
Posted on April 5, 2021

Every student enrolled this year in “Introduction to Cellular and Molecular Biology” received a package filled with the equipment they needed to perform their labs. The kits were boxed up in Schultz 105, the course’s teaching lab. “I’m very much looking forward to having the lab filled with students instead of boxes in the fall!” said Heather Thieringer, who has taught the course for 15 years.

Professors in engineering and the natural sciences have found a multitude of creative solutions, from setting up remotely controllable lab equipment to shipping kits of supplies to students’ homes to restructuring lab assignments to be done one at a time in the few still-operating lab spaces.

The instructors for Introduction to Cellular and Molecular Biology, taught this year to 80 students in the fall and 175 in the spring, packaged and shipped lab kits to students around the world. (On-campus students picked up their boxes at Frist Campus Center.)

The faculty also re-thought the goals of some labs, leading to changes that will likely stay in place long after the return of fully in-person instruction.

“There are skills beyond just what you do physically,” said Heather Thieringer, a senior lecturer in molecular biology who has taught this course for 15 years. “How do you analyze data? How do you present the data in a figure? We shifted focus to the kind of skills that have to do with scientific thinking: how to think about a hypothesis, how to design a controlled experiment.”

For example, every year until this one, students have cloned DNA early in the semester, she said. “We’d hand them test tubes and say, ‘This is your plasmid, this is your vector, this is the buffer. Pipette them all together and — oh, look, you cloned something!’’’

With that no longer possible, they turned the lab inside out, inviting the students to design the lab instead of executing it, using a program that Princeton faculty use in their own research labs. “We said, ‘This is the gene you want to clone, so you’re going to have to figure out how to do this: What enzymes should you use? How can you piece this together?’” Thieringer said.

It’s like teaching chefs not by handing them a recipe but asking them to write their own.

“I think it’s actually better for them to think about the thought process that happens before you get your hands on the equipment,” said Laurel Lorenz, a lecturer in molecular biology who also teaches the course.

While half of the class’s labs became fully virtual, designing experiments or analyzing existing data, the other half remained hands-on labs — which meant the instructional team had to get creative.

Each kit contained the equipment for a semester’s worth of biology labs, including safety glasses, gloves, a micropipette, pipette tips, petri dishes, microfuge tubes, a P51 blue LED light viewer box and much more.

For one lab, students added yogurt, which is available in most countries around the world, to the petri dishes and agar shipped by the University.

“That way they could culture bacteria, but nothing that they were growing was dangerous,” Thieringer said. “They were just growing the beneficial, probiotic bacteria that are in yogurt.”

That lab worked well in the fall, but had to be adapted for the spring, because with the dorm kitchens closed, many on-campus students no longer had access to cooktops or microwaves, or even refrigeration.

“I have to give a shout-out to the lab staff themselves,” Thieringer said. “They normally prepare all of the materials needed for getting 180 students into the lab for the week, and they have now pivoted and become experts at packing and shipping. Once, I came into the lab and saw them putting packaged test tubes on a shake table to make sure they would survive days of jostling in transit! We’ve gotten a kit, both semesters, to every single student, no matter where they are in the world.”