Benjamin Hafensteiner, a professor of chemistry at the University of Rochester, didn't plan on starting the fall semester as a star in a viral video, but that's exactly what happened. And in true fashion, Hafensteiner turned it into a teaching moment.

The video—with 8.7 million views and counting—was produced by a group of students who wanted to have some fun with Hafensteiner's general chemistry class. Prof. H, as Hafensteiner is called, agreed to give the students five minutes (not the 15 they requested) at the start of the year's first class. Someone posing as Hafensteiner laid down the law (no cell phones and no laptops) and warned them of the high failure rate, all the while destroying their hopes of getting into medical school. Once the fear had set in, the real Prof. H appeared, demanded to know who the charlatan was, and took over from the intruder, to the relieved applause of his students.

Prof. H used that moment to emphasize the difference between his class and the stereotyped notion of the college science experience.

"By introducing and making fun of some very common fears at the beginning of the class, I was able to set the record straight," said Hafensteiner. "My class is structured so that they can succeed."

Even before the first lecture begins, it's immediately clear to freshmen that Hafensteiner's general chemistry class is unlike anything they had in high school. For starters, instead of the typical 20 to 30 students in a high school classroom, Prof. H's class has ten times that many.

Hafensteiner is well-aware that his students are making a massive transition from high school—where there may have been a lot of hand-holding through their courses—to the University of Rochester, where they are expected to identify the resources needed in order to tackle problems on their own.

And Hafensteiner fully understands that many of his students didn't have a good chemistry experience in high school, even with a lot of hand-holding in a smaller class.

"Ninety-nine percent of the students who say they hated high school chemistry actually admit they disliked the teacher, which has nothing to do with the material," said Hafensteiner. "The challenge is to give those students the opportunity to appreciate the science."

Prof. H uses many of the tools and strategies adopted by other professors. He works hard to learn students' names, applies course material to everyday life, freshens up his lessons every semester, and employs i>clickers to get immediate feedback from students on class problems and discussions. But in the end, Hafensteiner's success as a teacher may boil down to access.

"He's the kind of professor who's very approachable," said Sharath Koorathota, a former teacher's assistant for Hafensteiner and one of the student producers of the hoax video. "He designs his lectures in a way that supports those taking chemistry for the first time, while still challenging everyone in the class."

Hafensteiner holds three office hours each week with anywhere from five to 15 students. They are not office hours as much as they are mini-classes that allow him to see up-close whether students are grasping the material.

Clearly Prof. H is making a difference. The University of Rochester Students' Association last spring named Hafensteiner Professor of the Year in the Natural Sciences, citing his support for the students and his "ability to make any class feel small."

"Sure, I can concentrate on turning the top three students into fantastic scientists," said Hafensteiner. "But if that's all I did, chemistry, as a discipline, would die. One of the most valuable things I can do is make sure all my students have an appreciation for the field."