One is bioethicist Ezekiel Emanuel, whose just-completed Health Policy and the Affordable Care Act class attracted more than 30,000 students - about 5,000 more than the Penn student body.
Emanuel's class is being outdrawn by Wharton School professor Kevin Werbach's Gamification, which starts Aug. 27 and will apply game-design techniques to business problems. Its 50,000 sign-ups top the Penn offerings so far.
Last month, Penn joined with the California Institute of Technology to invest $3.7 million in Coursera, which now offers 117 free courses from 16 official partners, including Stanford, Duke, and Princeton Universities. The University of California Berkeley and two Indian colleges also offer classes on Coursera but are not yet official partners.
The online courses mimic aspects of a traditional experience by having not only video lectures, but also strict class start and end dates, homework assignments, interactive quizzes, and discussion boards for students.
"Coursera feels like a good partner for us," said Deirdre Woods, interim executive director of Penn's Open Learning Initiative, which is for now primarily devoted to the Coursera project. "Penn is about rigor . . . and [Coursera's] philosophy was very much in line with that."
Of Penn's 16 online courses, two are currently in session and more will start up in the next several months.
The focus on medicine was not deliberate, explained Coursera cofounder and co-CEO Andrew Ng. However, the strength of its medical school makes the dominance of health-related classes "an obvious choice" for Penn, which so far is the only Philadelphia medical school - and one of the few nationwide - to present its classes online.
The medical courses are geared for a lay audience - no prerequisite courses or specialized knowledge needed - unlike Coursera offerings in some other areas, such as computer science.
Emanuel's class on the Affordable Care Act just ended, but lectures are still available. It covered such topics as the surging costs of U.S. health care and how the law will raise insurance coverage.
Emanuel has another course in the works, to start in early 2013, called Rationing and Allocating Scarce Medical Resources. He will cover such issues as how to deal with limited supplies of donor organs and vaccines.
A more informed professor to teach the health-care law is hard to imagine. Emanuel served in the Obama administration as a special adviser for health policy from 2009 to 2011, when he worked on the Affordable Care Act.
Emanuel, who holds a joint appointment at both Perelman and Wharton, fully supports online education and is "heavily engaged" in all aspects of his class. In fact, he started videotaping his lectures before any mention of a Penn-Coursera partnership.
While his brick-and-mortar lectures last an hour and a half, the Coursera version breaks them down into easily digestible, 20-minute videos that also feature pop-up interactive quizzes throughout.
With Coursera, Emanuel hopes his work will reach a wider audience, including those who could "never in a million years" come to Penn. So far, it's working. About half of his 30,000 students hail from outside the United States.
Ethan Helhowski, a junior studying human-resource management at Bentley University in Waltham, Mass., finds the course "eye-opening."
"My grandfather and uncle are both doctors, and I'm now able to grasp some of the ideas and words they use," Helhowski said. He took Emanuel's class, along with two more from Penn med: pediatrician Paul Offit's Vaccines and Emma Meagher's Fundamentals of Pharmacology.
Even though Penn's first four courses are either under way or finished, students may sign up and watch prior lectures, but they won't be able to get feedback on past homework or quizzes.
Since the assignments consist of short essays rather than multiple-choice questions, Health Policy takes advantage of Coursera's peer grading system. Students are trained to grade others' work. Every student is asked to grade five other assignments, and in turn gets feedback from five other students.
Unlike humanities classes, Ng said, the site's quantitative or technical courses can use multiple-choice tests that are easier to grade with computers.
After a course has ended, Woods said, access to video lectures and discussion boards may be temporarily closed. This falls in line with Coursera's still-evolving philosophy of taking the course in its entirety, rather than watching a lecture here and there.
With its more rigorous format, Coursera distinguishes itself from other online education platforms such as iTunes U and Khan Academy, which offer sets of video lectures for students to peruse freely.
The online-class trend is catching on quickly.
"We get e-mails almost every day from universities asking to partner with us," said Ng, a Stanford computer science professor who also directs the university's artificial intelligence lab and founded Coursera with his colleague Daphne Koller.
The two had discussed the possibilities of online education for years. They finally put up their platform - not yet called Coursera - in the fall of 2011 with three classes. The results were encouraging, with each enrolling about 100,000 students.
Ng and Koller then decided to reach out to other universities. Coursera started with four schools - Stanford, Princeton, the University of Michigan, and Penn - and last month grew to 19, including five international institutions.
Now the site boasts more than a million students from 196 countries - with almost two-thirds from outside the United States.
The number of offerings keeps expanding. Penn soon plans to add classes in economics and one on attention deficit hyperactivity disorder. Early next year, more within the fields of business, computer science, physics, nursing, and medicine will be added.
Recently, the Massachusetts Institute of Technology and Harvard University started their own platform, edX, similar to Coursera in its rigorous approach. They also plan to expand to other universities, with Berkeley as a partner.
Some professors believe that such courses degrade the overall quality of education. Michael Pravica, a physics professor from the University of Nevada at Las Vegas, believes that an all-online course without the in-person support of a teacher is "very wrong."
"I just don't think the students are going to learn as much - not even close to what they would learn in a live course," Pravica argues.
Pravica stresses that he supports online supplementary materials at brick-and-mortar institutions, and that he offers them for his students.
Penn Provost Vincent Price agrees that "personal, face-to-face, and highly collaborative" teaching will remain at the school's core. Penn's foray into online education is a way of "extending and advancing" that foundation.
So why would an institution like Penn give away its prized academic content for free?
It won't for long.
Both Woods and Ng said that plans for monetizing the site are under way. "Right now we are working with the model and trying to get it right," said Woods.
Emanuel said that extracting profits from online may be difficult: "How can we get returns other than the halo effect? If you start charging at the front end, people may not sign up; if you charge at the back end, they may not finish the course."
Right now, Coursera is giving away free unbranded certificates after successful completion of a class, but Ng said some universities are considering selling branded certificates. Another possible way of generating revenue, Ng said, is charging for putting employers in touch with high-performing students.
Penn's Price found the company's goals "compelling" and said that, rather than remaining in the backseat, Penn "should take a leadership role as one of Coursera's founding partners and do our part to help the venture succeed."
Coursera has only 30 employees so far, but the company is rapidly growing. Ng estimates it has been hiring one to two employees a week.
"High-quality education is a universal human right, and technology can bring it to everyone," said Ng. "I'd like to see a future where Penn is teaching not to thousands of students, but to millions."
Meeri Kim can be reached at email@example.com.