Élite educators used to be obsessed with “faculty-to-student ratio”; now schools like Harvard aim to be broadcast networks. Illustration by Leo Espinosa

Gregory Nagy, a professor of classical Greek literature at Harvard, is a gentle academic of the sort who, asked about the future, will begin speaking of Homer and the battles of the distant past. At seventy, he has owlish eyes, a flared Hungarian nose, and a tendency to gesture broadly with the flat palms of his hands. He wears the crisp white shirts and dark blazers that have replaced tweed as the raiment of the academic caste. His hair, also white, often looks manhandled by the Boston wind. Where some scholars are gnomic in style, Nagy piles his sentences high with thin-sliced exposition. (“There are about ten passages—and by passages I simply mean a selected text, and these passages are meant for close reading, and sometimes I’ll be referring to these passages as texts, or focus passages, but you’ll know I mean the same thing—and each one of these requires close reading!”) When he speaks outside the lecture hall, he smothers friends and students with a stew of blandishment and praise. “Thank you, Wonderful Kevin!” he might say. Or: “The Great Claudia put it so well.” Seen in the wild, he could be taken for an antique-shop proprietor: a man both brimming with solicitous enthusiasm and fretting that the customers are getting, maybe, just a bit too close to his prized Louis XVI chair.

Nagy has published no best-sellers. He is not a regular face on TV. Since 1978, though, he has taught a class called “Concepts of the Hero in Classical Greek Civilization,” and the course, a survey of poetry, tragedy, and Platonic dialogues, has made him a campus fixture. Because Nagy’s zest for Homeric texts is boundless, because his lectures reflect decades of refinement, and because the course is thought to offer a soft grading curve (its nickname on campus is Heroes for Zeroes), it has traditionally filled Room 105, in Emerson Hall, one of Harvard’s largest classroom spaces. Its enrollment has regularly climbed into the hundreds.

This spring, however, enrollment in Nagy’s course exceeds thirty-one thousand. “Concepts of the Hero,” redubbed “CB22x: The Ancient Greek Hero,” is one of Harvard’s first massive open online courses, or MOOCs—a new type of college class based on Internet lecture videos. A MOOC is “massive” because it’s designed to enroll tens of thousands of students. It’s “open” because, in theory, anybody with an Internet connection can sign up. “Online” refers not just to the delivery mode but to the style of communication: much, if not all, of it is on the Web. And “course,” of course, means that assessment is involved—assignments, tests, an ultimate credential. When you take MOOCs, you’re expected to keep pace. Your work gets regular evaluation. In the end, you’ll pass or fail or, like the vast majority of enrollees, just stop showing up.

Many people think that MOOCs are the future of higher education in America. In the past two years, Harvard, M.I.T., Caltech, and the University of Texas have together pledged tens of millions of dollars to MOOC development. Many other élite schools, from U.C. Berkeley to Princeton, have similarly climbed aboard. Their stated goal is democratic reach. “I expect that there will be lots of free, or nearly free, offerings available,” John L. Hennessy, the president of Stanford, explained in a recent editorial. “While the gold standard of small in-person classes led by great instructors will remain, online courses will be shown to be an effective learning environment, especially in comparison with large lecture-style courses.”

Some lawmakers, meanwhile, see MOOCs as a solution to overcrowding; in California, a senate bill, introduced this winter, would require the state’s public colleges to give credit for approved online courses. (Eighty-five per cent of the state’s community colleges currently have course waiting lists.) Following a trial run at San José State University which yielded higher-than-usual pass rates, eleven schools in the California State University system moved to incorporate MOOCs into their curricula. In addition to having their own professors teach, say, electrical engineering, these colleges may use videos by teachers at schools such as M.I.T.

But MOOCs are controversial, and debate has grown louder in recent weeks. In mid-April, the faculty at Amherst voted against joining a MOOC program. Two weeks ago, the philosophy department at San José State wrote an open letter of protest to Michael J. Sandel, a Harvard professor whose flagship college course, Justice, became JusticeX, a MOOC, this spring. “There is no pedagogical problem in our department that JusticeX solves,” the letter said. The philosophers worried that the course would make the San José State professor at the head of the classroom nothing more than “a glorified teaching assistant.” They wrote, “The thought of the exact same social justice course being taught in various philosophy departments across the country is downright scary.”

Nagy has been experimenting with online add-ons to his course for years. When he began planning his MOOC, his idea was to break down his lectures into twenty-four lessons of less than an hour each. He subdivided every lesson into smaller segments, because people don’t watch an hour-long discussion on their screens as they might sit through an hour of lecture. (They get distracted.) He thought about each segment as a short film, and tried to figure out how to dramatize the instruction. He says that crumbling up the course like this forced him to study his own teaching more than he had at the lectern.

“I had this real revelation—I’m not saying ‘epiphany,’ because people use that word wrong, because an epiphany should be when a really miraculous superhuman personality appears, so this is just a revelation, not an epiphany—and I thought, My God, Greg, you’ve been spoiled by the system!” he says. At Harvard, big lecture courses are generally taught with help from graduate students, who lead discussion sessions and grade papers. None of that is possible at massive scales. Instead, participants in CB22x enroll in online discussion forums (like message boards). They annotate the assigned material with responses (as if in Google Docs). Rather than writing papers, they take a series of multiple-choice quizzes. Readings for the course are available online, but students old-school enough to want a paper copy can buy a seven-hundred-and-twenty-seven-page textbook that Nagy is about to publish, “The Ancient Greek Hero in 24 Hours.”

Lecturing can seem a rote endeavor even at its best—so much so that one wonders why the system has survived so long. Actors, musicians, and even standup comedians record their best performances for broadcast and posterity. Why shouldn’t college teachers do the same? Vladimir Nabokov, a man as uncomfortable with extemporaneity as he was enamored of the public record, once suggested that his lessons at Cornell be recorded and played each term, freeing him for other activities. The basis of a reliable education, it would seem, is quality control, not circumstance; it certainly is not a new thought that effective teaching transcends time and place. Correspondence courses cropped up in the nineteenth century. Educational radio appeared in the twenties and the thirties. The U.K.’s Open University, which used television to transmit lessons to students, enrolled its first students in 1971.