“I'm constantly challenging myself”

Cécile Hébert teaches the basic concepts of general physics to around 200 first-year students from outside the physics section. © Alain Herzog 2019 EPFL

Cécile Hébert teaches the basic concepts of general physics to around 200 first-year students from outside the physics section. © Alain Herzog 2019 EPFL

Cécile Hébert, an associate professor who frequently tests out new teaching tools and methods, has been awarded the prize for best physics teacher at EPFL.

In the middle of the physics section, there’s one office surrounded by greenery – cherry tomato plants, herbs and lemon tree. That’s Cécile Hébert’s. The researcher with a green thumb became EPFL’s first female physics professor 12 years ago and is now the head of EPFL’s Electron Spectrometry and Microscopy Laboratory. And she seems perfectly at ease in her pioneering role. Hébert constantly challenges herself and is not afraid to test out new teaching tools and methods, an approach that helped her win this year’s prize for best physics teacher at EPFL.

Hébert – a native of France who specializes in transmission electron microscopy – does not have an easy task. Her job is to convey the basic concepts of general physics every year to around 200 first-year students from outside the physics section. It’s a dense topic that she covers in three hours of lectures and three hours of exercises every week. “I try to get them used to taking a problem, breaking it down, modeling it, using their knowledge of math and challenging the result. But not all of my students learned physics in the same way, and some have trouble with this approach.”

New interactive tools

Several years of back-and-forth with a high-school teacher have helped Hébert pinpoint her students’ difficulties and adapt the exercises. And since the concepts of physics can be tested anywhere, she keeps her class’s attention through experiments drawn from everyday life. When taking a ride on Lausanne’s metro, for example, you simply need to close your eyes just before the brakes are applied to feel the force of inertia.

To encourage her students to engage, Hébert also uses SpeakUp, an app that allows students to ask questions anonymously and vote for the questions they think are most relevant. “And then, in class, I answer the questions that get the most votes. The system works well,” she says. Since the spring semester, she has also created her own Jupyter Notebooks, which are programmable exercise books that model experiments and show students the equations behind them. “This avoids the black-box syndrome of other programs, which is not helpful when you’re training engineers.”

Overcoming obstacles

Hébert’s architect parents did not necessarily groom her for a career in science, yet studying physics and mathematics was an obvious choice for her in high school. She went on to specialize in physics, earning a PhD from the Ecole Centrale Paris and doing post-doctoral work at the Vienna University of Technology. Has she ever run into obstacles in what is still a male-dominated environment? “In my work, I’ve never felt that I was discriminated against as a woman,” she says. “However, the way society is organized, at least in Switzerland, is a problem, particularly in terms of childcare.” Several times, she has received comments on her decision to pursue her career as a full-time professor while raising two children. And on occasion, unable to find childcare, she had to bring her daughter and son, now aged 15 and 16, along to lectures. “When I had no other choice, I brought them to work with me. They would sit next to me and draw while I taught. They were always very well-behaved,” she says with a smile. These days her children are on track to study science as well.

Hébert originally wanted to become an astrophysicist, but her sights are now set on the ground: she’s working with James Badro to analyze the properties of the materials that make up the earth’s mantle. She’s doing this using an electron microscope, which offers a resolution that’s 100,000 times greater than that of an optical microscope and provides extremely precise measurements. Hébert is as keen to learn as she is to teach. A few years ago, she visited Tanzania through a foundation promoting local education. She gave a week of intensive classes on thermodynamics to high-school teachers.

In early 2019, together with her colleague Duncan Alexander, Hébert created a MOOC on transmission electron microscopy. They now use this MOOC in their Master’s course for physics and materials science students. They’ve been teaching the course for two years, using a flipped classroom approach at times, and giving students the opportunity to use an electron microscope. “Since adopting this format, we’ve seen improved exam results, with the average grade rising from 4.46 to 5.24. It’s been an exhausting journey, but well worth it.”