But all jokes aside, professors and students indicate that demonstrations add excitement, suspense, and memorability to any lecture.

“Having nature tell you how she works is the most convincing tool because after all, in science, we’re trying to deduce how the world works,” said Eric Mazur, a physics and applied physics professor who researches science education strategies.

But he said that a demonstration is not necessarily effective in a vacuum, so to speak—the lecturer must properly prepare students to absorb the meaning of the demo.

Mazur has conducted studies evaluating whether predicting and discussing demo outcomes affect the degree to which students remember the principles illustrated.

“Adding just the prediction increased the students’ ability to correctly remember very significantly,” Mazur said.

He said that when a new mental model is required to explain the result of a demo, it’s crucial for students to take time to reconstruct their mindsets before moving on—or else they are in danger of remembering the principle incorrectly.

“What happens is that your brain adjusts your memory to the model rather than the model to the observation,” he said. But when students invest in thinking before a demo, “if there is a cognitive dissonance, it’s stronger, and they’re more likely to say ‘woah, let me figure this out, why was I wrong?’” he said.

Kirshner commented that a sense of danger—especially the danger that the professor might get injured—is always exciting (and potentially amusing) for students.

“When they’re exploding things and they put on safety goggles, you know they’re really serious,” said Mary M. Griffin ’13, a student in Physical Sciences 1 who says that demos in the class serve not only to wake students up but give them an “exciting context in which to absorb the material they’re learning.”

By working thoughtfully—and often quite inconspicuously—at the nexus of construction, creativity, innovation, and education, the demo team is able to spread their enthusiasm for science to a wider audience through demonstrations large and small, complex and simple.

“Look, science is real, tangible things—you want to hear it, see it, feel it, smell it, taste it,” said Tucci, in enumerating the virtues of a well-executed demonstration. “It’s not just symbols on a blackboard anymore, it’s real, visceral stuff.”

—Staff writer Julie R. Barzilay can be reached at jbarzilay13@college.harvard.edu.