How Harvard’s Star Computer-Science Professor Built a Distance-Learning Empire

David Malan, who films CS50’s lectures in 4K high resolution, has written that the course’s high production value is “part of its pedagogy,” allowing students who tune in remotely to “feel no less a part of the classroom than students on campus.”

Gabriel Guimarães grew up in Vitória, Brazil, in a yellow house surrounded by star-fruit trees and chicken coops. His father, who wrote software for a local bank, instilled in him an interest in computers. On weekends, when Guimaraes got bored with Nintendo video games, he programmed his own. In grade school, he built a humanoid robot and wrote enough assembly code to make it zip around his home. In Vitória, an island city, his most ambitious peers dreamed of attending university in São Paulo, an hour away by plane. Guimaraes set his sights on the Massachusetts Institute of Technology. By the time he was in high school, M.I.T. had released hundreds of its classes, free of charge, on the Internet, as a series of massive open online courses, or moocs. Guimaraes sampled the introductory computer-science class, but he found the lecturer, a “white-haired guy in front of a blackboard,” crushingly dull. In 2011, trawling YouTube for other course material, Guimaraes clicked on a lecture from Harvard’s introductory computer-science class, CS50, which was taught by a young professor named David Malan. Almost instantly, Guimaraes told me, he felt himself “hypnotized.”

Malan, who had glossy black hair and an energetic mien, lectured from a grand auditorium on Harvard’s campus. In the first class, he illustrated an algorithm called binary search by inviting a volunteer onstage to find “Mike Smith” in the Yellow Pages; at Malan’s urging, the student opened up the phone book to a random spot, tore off the half of the book without the right name, and then repeated the process, halving the volume again and again, until only the desired page remained. Malan’s assignments, too, eased students into the arcana of computer science. Before learning C, a low-level programming language with finicky syntax, they created animated games in Scratch, a visual programming language designed for children. For a forensics problem set, inspired by a summer that Malan spent working in a district attorney’s office, students were asked to write code to restore a set of deleted photo files. “It felt like the coolest video game I’d ever gotten my hands on,” Guimaraes said.

On Harvard’s campus, CS50 culminates in a festive exposition, where students show off their final coding projects and hobnob with technical recruiters from companies like Facebook and Google, many of whom are alumni of the class; Malan provides a bevy of free paraphernalia, including CS50-branded stress balls and T-shirts that read, “I TOOK CS50.” In Brazil, Guimaraes decided to conduct his own final project: a re-creation of Malan’s course materials and lectures in Portuguese. In his sophomore year of high school, he taught CC50—Ciência da Computação Cinquenta—to his peers, during eleven weeks of the fall term. When Guimaraes arrived for the first class, bearing, as Malan did, a gargantuan sheet cake as a welcome treat, he found about a hundred students snaking out the door. Dressed in a baggy Harvard shirt that he’d bought online, he delivered Malan’s first lecture, repeating the phone-book demonstration with an old dictionary. CS50’s course materials were freely distributed under a Creative Commons license, but, as a courtesy, Guimaraes had e-mailed Malan’s staff a heads-up about his project. During the sixth week of his lectures, he received a gift box from Malan, stuffed with CS50 swag.

Malan, who took over CS50 in 2007, was a pioneer in distributing Harvard course materials online for free. In 2012, Harvard and M.I.T. launched their own online-learning platform, edX, which today offers several thousand moocs—both digital editions of existing university courses and original certificate programs designed by Microsoft, I.B.M., and other technology giants. But few, if any, combine the institutional credibility, the enormous reach, and the zealous engagement of Malan’s. In the decade since Guimaraes took it, CS50 has inspired satellite operations on every continent except Antarctica. Though most of the students who sign up for the edX version—more than two million to date—quit before finishing, those who stick with it often become diehards: earlier this year, in Baghdad, students restaged Malan’s project fair at al-Hikma University with identical trimmings, down to the emoji-shaped balloons and the custom “debugging” rubber ducks. To promote the expansion of CS50, Malan films welcome teasers for the remote cohorts, hosts annual educator workshops, and helps prop up outposts around the world. CS50 is less a single course than an “ecosystem of courses,” as one staff member put it, with spinoffs designed for specific audiences: lawyers, business students, gamers. In 2015, Harvard’s computer-science department launched an unprecedented partnership with Yale, live-streaming Malan’s lectures from Cambridge to New Haven.

Malan’s investment in virtual learning has transformed the way that students engage with the class at its home base, too. CS50 is one of Harvard College’s most popular courses; it’s also the only one that students can watch live, in high definition, from their dorms. In the past, Malan has encouraged them to do so, writing, in a blog post from 2016, that it might well be “a better educational experience to watch CS50’s lectures online than attend them in person.” Prioritizing remote teaching to such an extent is still a rarity among Harvard professors. Even Michael Sandel’s Justice, another flagship Harvard lecture course, whose online counterpart predates CS50 and was broadcast on PBS, has little of Malan’s technological infrastructure. In March, when the coronavirus pandemic forced universities across the country to migrate classes online, no more than five hundred Harvard instructors had virtual teaching experience, the university’s president, Lawrence Bacow, told me in an e-mail. In a matter of days, the number “jumped to about three thousand,” the size of Harvard’s entire teaching staff.

For many professors, the sudden transition was a struggle. For Malan, it was the natural extension of a decade’s worth of experimentation. “Our team is fortunate to have been doing this blend of education for quite some time,” he told me recently. “For us, it was very straightforward.” Malan’s contract at Harvard allows him to focus almost exclusively on CS50; even the research he publishes centers mainly on the class. In the spring, he happened to be piloting a small version of CS50, historically a fall course, using online-only lectures filmed in the previous term. The pandemic prompted him to move parts of the curriculum—office hours, a weekly tutorial, the project fair—to Zoom. But, while his colleagues were scrambling to retool their classes for virtual platforms—troubleshooting unfamiliar technology, shortening lessons, building in interactivity—the substance and presentation of CS50, as one student wrote in an end-of-term evaluation, “pretty much stayed the exact same.” Malan’s method of remote teaching is not easily replicable; CS50’s pyrotechnics would not be possible without an unusually deep well of resources and his own fanatical commitment. But, as universities attempt to reopen safely in the fall, with online learning at the forefront, the course’s spread and success provide a glimpse of where higher education might be headed.

One muggy morning in June, Malan visited Harvard’s campus. Sanders Theatre, where he lectures, was still officially closed, but a few members of CS50’s staff had received special permission to enter. I found Malan at a side door. He was wearing a mask and, over one shoulder, carried a backpack containing two laptops. Inside, signs in Harvard’s colors encouraged hand washing and social distancing. Doors had been propped open, to reduce human contact with knobs and handles; a red brick, stationed on the floor outside the bathroom, could be kicked aside to signal that someone was inside. Harvard had not yet finalized its reopening plans, but the university had released an interim report earlier in the week, stating that, “regardless of whether students are on campus, learning will be remote next year, with only rare exceptions.” For more than two months, Malan had been holding CS50’s office hours online, both for his Harvard class and, separately, for outside students, in sessions open to the public. Now he was going to try streaming his office hours from Sanders, to see how it would feel to teach there, in the fall, with only a virtual audience. More than a thousand students, from a hundred and nine countries, had registered to attend the day’s session.

In 2008, when Malan first moved CS50 to Sanders, from a nondescript amphitheatre in Harvard’s Sever Hall, the class, at around three hundred students, occupied only the orchestra section and a segment of the mezzanine. By 2014, enrollment had exceeded eight hundred students, and many of them had to watch from the balcony. Sanders is one of the university’s largest performance venues, a booming, stadium-style hall of burnished red oak. Malan’s team equipped it with five cameras—some manned by humans, others robotically controlled—and, at the back of the mezzanine, a makeshift production booth. As in a “live sporting event,” Malan explained, the students who watch CS50 in real time might see the camera cut to a closeup of him, or to a gigantic projection of his computer screen, or to a wide shot from the robotic slider, which captures the silhouettes of spectators in the front of the house. Whereas many online instructors chop up their lectures into short segments, interspersed with exercises designed to monitor progress and sustain engagement, Malan publishes his uninterrupted. He often teaches in front of a green screen, so that his team can turn his Web browser into a giant backdrop in post-production.

Malan’s remote-teaching setup involves a host of technology, including a seven-foot-wide interactive computer screen, called a Microsoft Surface Hub.

Among his international fans, Malan is something of a celebrity. His signature outfit is a thin black sweater and dark jeans, which, several of his students and colleagues noted, lends him a faint resemblance to Steve Jobs. On his left wrist, he sports an Apple Watch and what seems like a silver bracelet but is actually the pull chain for a house lamp, purchased from Home Depot—because, as he put it, “I’m not a fan of expensive things.” He speaks and writes in an odd, anachronistic style, using words like “daresay” and “thereto” and inverting subjects and auxiliary verbs, as in “At 5 a.m. will some Harvard shuttles take us to ihop.” (Malan traces this habit to an early fascination with the great orators of American history.) While lecturing, he has a tendency to break a sweat. Though he maintains verified Facebook, Twitter, and Instagram accounts, where students tag him in posts celebrating their progress or despairing of their runtime errors, Malan is guarded on the subject of his private life. In every one of our Zoom interviews, and in every session of CS50 office hours hosted from his home, he appeared against a backdrop of solid white.

In Sanders, Malan hopped onstage, where he fiddled with a lapel mic and attached a wireless transmitter to his belt. “Testing, one, two,” he said. “Can production hear me?” Six members of CS50’s staff were on a Zoom call, their faces magnified on a seven-foot-wide interactive computer screen, called a Microsoft Surface Hub, which had been positioned, on wheels, at the edge of the stage. CS50 has three full-time production technologists. They work with Malan to film, edit, and upload not only the course’s lectures, office hours, and how-to videos but also a slew of ancillary—some might say superfluous—entertainment material: outtakes, sizzle reels, behind-the-scenes snippets, a piano performance of one of CS50’s original theme songs, and a thirteen-part homage to “Citizen Kane,” starring Malan as himself. (“They were filming shit all the time,” one former course assistant, who spent a summer working in CS50’s spacious office, told me.)

The only staff members physically present were Brian Yu, a recent Harvard grad who is now a preceptor, and Andrew Markham, one of Malan’s production technologists. Markham, a buff thirtysomething, stood on a stepladder, in a coral-colored CS50 T-shirt, positioning two digital cameras so that they peeked over the top of the Surface Hub. The plan was to jury-rig the screen into a giant laptop: Malan and Yu, who was co-hosting the session, would stand onstage at lecterns twelve feet apart and speak into these cameras; the students would appear, just as the staff did now, at jumbo scale in Zoom’s gridded “gallery view.” As Markham paced the stage, snapping a director’s clapper board in front of each camera, Malan scurried down into a corner of the orchestra section. He planned to start the office hours by Zooming in from his cell phone and surprising students with a tour of the theatre. Malan often greets his class with the first phrase that new programmers learn to generate: “Hello, world!” he said into his camera, when the call began.

Behind the scenes, Malan’s production team screened and queued up a selection of callers to ask questions. The group included a fifteen-year-old from Athens, a dentist from Buenos Aires, and a Dominican children’s educator living in Texas, plus others from Canada, England, Kenya, and Morocco. “It’s an honor, first of all,” Sugeet, an architecture student from Dharwad, India, said, when it was his turn, before posing a question about how to apply Malan’s coursework to the design of buildings. Khudeja, a stay-at-home mother living in Dubai, asked whether it was possible to build an app on one’s own. A. J. Veneziano, a Harvard undergraduate in a Pete Buttigieg T-shirt, wondered about computer science’s applications within the humanities. “I’m taking CS50 over the summer, because (a) I was too scared to take it in the fall, and (b) I’m a history major, so I’d never had any exposure whatsoever to coding,” he said.

Later, on a private Zoom call, Veneziano told me that he’d enrolled in CS50 to pass time while quarantining at his childhood home, in Dayton, Ohio. Like the rest of Harvard’s student body, he’d learned of the school’s closing plans on March 10th, in an e-mail from the dean of the college. He had five days to pack up and leave his dorm. Despite the best efforts of his professors, Veneziano told me, the transition to remote learning had affected the quality of his education. His course on natural disasters scrapped its labs. The professor of his largest class, on the Hebrew Bible—a septuagenarian who struggled with screen sharing—had arranged for his lectures to be recorded even before the pandemic began. On campus, Veneziano said, almost all of the course’s two hundred students attended anyway. Once the lectures moved to Zoom, no more than thirty showed up each time. Malan’s lectures, Veneziano said, are “years ahead of what I experienced this spring.”

I had assumed that Veneziano was taking CS50 through the university’s summer session: Malan is offering the course again, as he did in the spring, with lectures from the previous fall released weekly. But, when I asked how far along the class was, Veneziano looked confused. “I’m taking the free version,” he said, referring to the mooc, which is self-paced, and is open to anyone, anywhere, through edX. Unlike Harvard’s version, the mooc does not include discussion sections, so, for help with homework, Veneziano had been consulting CS50’s StackOverflow page, one of about a dozen forums where Malan’s edX students troubleshoot problems together. Veneziano wouldn’t get academic credit for his work: Harvard College does not grant credit for any edX courses, because, as a university spokesperson said, it is “difficult to verify and regulate participation and academic integrity.” To Veneziano, though, there was no point paying for identical lectures and problem sets, especially when he was eight hundred miles away from campus. “It’s just a no-brainer,” he told me.

Harry R. Lewis, a former dean of Harvard College, was one of the university’s first computer-science professors. In the seventies, when he was a graduate student at Harvard, the school didn’t call what he and his classmates were studying computer science: they earned degrees in physics, mathematics, or, in Lewis’s case, applied mathematics. Lewis, who retired this summer, joined the faculty in 1974, when programmers at Harvard worked from remote terminals connected to a so-called minicomputer, which occupied its own room on the first floor of the university’s Science Center. One of his early students was Bill Gates, who later dropped out of Harvard to launch the venture that would become Microsoft. Lewis recalled, though, that the university’s leadership remained “blind to the future of computing.” In 1978, he proposed that Harvard establish a separate computer-science major. Some of his fellow-professors scoffed at the thought. “What’s next, an automotive-engineering program?” Lewis remembers a senior colleague telling him.

By the time Malan entered Harvard as a freshman, in 1995, the rise of the Internet had made the field impossible to dismiss. The dot-com bubble was beginning to inflate. Larry Page and Sergey Brin, two precocious Ph.D. students at Stanford, were busy at work on an early version of a search engine called BackRub, which they’d eventually rename Google. But Malan, the son of an advertising executive and a middle-school teacher, planned to major in government. He’d grown up in Stamford, Connecticut, where, for as long as he could remember, Saturdays were spent on history papers and Sundays on English essays. His family’s computer was an early Macintosh model, which Malan used to laser-print written assignments and play King’s Quest. As he likes to tell it, though, he cared little about how computers worked. At preparatory school, he recalled, “I remember looking in through the glass window of the computer lab at some of my friends doing this geeky activity—heads down, typing away. I never took an interest in that.”

In the fall of his sophomore year, on a whim, Malan sampled CS50 during the semester’s “shopping period,” and decided to stick with the class because he could take it pass-fail. It was taught by Brian Kernighan, a visiting professor, who had made his name at AT&T’s famed Bell Labs and co-written the comprehensive guide to C programming. Kernighan’s assignments lacked the theatrics of the present-day CS50, but Malan, after a few lectures, was “hooked.” Every Friday, when the next week’s problem set was released, he’d take his very first laptop—the seven-pound PowerBook 540c, which featured the world’s first trackpad—to the stacks of Harvard’s Widener Library and get to work. Several weeks into the semester, realizing that he wouldn’t get credit for the major if he didn’t earn a grade in the class, he rushed to the registrar’s office just in time to adjust his pass-fail status.

Malan got his start teaching thanks to Henry Leitner, who taught the second course in the major’s introductory series. They met at the end of the term, when Malan visited Leitner’s office to contest his final grade. (It was an A-minus.) Struck by Malan’s gumption, Leitner, at the time an associate dean in Harvard’s Division of Continuing Education, ended up hiring him as a teaching assistant at the university’s extension school. In the spring of Malan’s senior year, facing a last-minute staffing shortage, Leitner tapped Malan to teach a full course, warning him not to let on to his students that he was still an undergraduate. Malan’s preferred attire back then was a suit and suspenders, but he showed hints of the pedagogical panache that would become his brand, enlivening his presentations with WordArt animations and proffering snappy factoids to make the material relevant. In his first class, held in a poorly lit lecture hall, he scrawled a trivia question on the board: “As of mid-1998, how many PCs were connected to the Internet? (If you’re not sure what the Internet is, that’s O.K.)” The answer was sixty million. “You can only imagine what the numbers will be like come the year 2000,” Malan added. At the end of that semester, Leitner told me, “David’s ratings were five out of five on every scale.”

Malan’s signature outfit is a thin black sweater and dark jeans, which lends him a faint resemblance to Steve Jobs.

CS50’s full-time production technologists work with Malan to film, edit, and upload not only the course’s lectures, office hours, and how-to videos but also a slew of ancillary entertainment material.

After graduation, Malan did a stint teaching high-school math in Franklin, Massachusetts, and spent the next year at a wireless startup in Philadelphia, where he continued telecommuting for Harvard: Leitner was piloting the extension school’s first online courses. Distance learning was not a novelty; Leitner’s predecessors had experimented with radio and television broadcasts in the fifties, and had even used a kinescope, in the sixties, to record course material for Navy personnel on submarines. But the new paradigm involved video downloads and virtual forums. Leitner told me that he deliberately started with computer-science courses, hoping that the students would be savvy enough to spare him a “tech-support nightmare.” Real-time, Zoom-style video platforms did not yet exist, but Malan’s first courses, which featured prerecorded lectures and PDF problem sets, didn’t differ much in essence from the average mooc today. “The video quality, of course, was much worse,” he said. “But, in spirit, it was very similar.”

In 2002, at Leitner’s suggestion, Malan enrolled in Harvard’s Ph.D. program, where he conducted research under the supervision of Michael D. Smith, who was then the teacher of CS50. As a graduate student, still teaching at the extension school, Malan became the first Harvard instructor to make an entire course available, for free, in audio and video formats. When Smith was promoted to a dean position, in 2007, Malan asked Leitner to lobby for him as Smith’s replacement. At the time, CS50 still had a reputation for being dry and demanding. “I would lose students after the first week of class,” Smith told me. Malan’s aim, from the beginning, was not just to teach the course but to transform it, in the hopes of attracting more students, like him, who had no previous affinity for computer science. Malan told me that he’d always admired evangelists he’d seen on TV, for their “ability to persuade others through speech.” As a teacher, he said, “I think a lot of my interest in the theatrical is honestly driven by some insecurity about not wanting the audience to be bored.”

Over several years, Malan rejiggered the CS50 syllabus, overhauled the problem sets, and built the infrastructure for his videography. He gathered a team of staffers to help him develop specialized learning tools, including a video player with searchable lecture transcripts and a program that translates cryptic computer-generated error messages into user-friendly prompts. He also introduced the kinds of perks and activities that were less common to college classes than to the companies where Harvard computer-science grads ended up: Google, Apple, Facebook. At many events—the course fair, Puzzle Day, the catered, nightlong hackathon—he hired photographers and set up photo booths with pompoms, plushies, a custom-made David Malan Muppet. I started studying computer science at Yale the same semester that CS50 was introduced there. Though I never took the class, photographs from Malan’s events would crop up on my Facebook timeline, every fall, with the same coördinated intensity as ads for a-cappella auditions or sorority rush.

Not unlike a tech entrepreneur “disrupting” industry regulations, Malan has a habit of flouting academic norms to facilitate CS50’s expansion. In 2014, he successfully lobbied Harvard to grant CS50 the sole exemption from a policy prohibiting students from enrolling in two classes scheduled at the same time; double-booked students, he argued, could just watch his lectures later. The same year, in response to rampant cheating within CS50—a problem in most computer-science classes—he introduced a “regret clause” to the syllabus, allowing students to evade university-wide sanctions if they confessed to cheating on an assignment within three days of submitting it. (A few years later, more than sixty CS50 students, a tenth of the class’s total enrollment, reportedly ended up going in front of the disciplinary board anyway.) According to the Crimson, Malan and Harvard at one point filed competing applications to trademark the name CS50 and “This is CS50,” the course’s tag line. (Malan, who withdrew his applications after Harvard moved to block them, told me that the newspaper misconstrued the incident, adding, “I was long in communication with Harvard’s Office of General Counsel.”)

CS50’s size and privileged status have rankled some at Harvard. In 2015, after CS50 started hosting its office hours in the hallowed Loker Reading Room, in Widener, the main campus library, a group of students launched a satirical “Take Back Widener” campaign, to wrest the space from “our CS50 overlords.” That year, the Crimson published an editorial calling on the university to “curtail CS50,” comparing the course to a “proselytizing faith-based religion.” On a short-lived blog collecting anonymous testimonies about CS50, one student wrote, “What sort of a class sells merchandise? And how can they afford t shirts for 800 people, along with stress balls, sunglasses, and more? Where is this money coming from?”

Money was not something that either Malan or representatives from Harvard were eager to discuss. “Without getting into specifics, it can be said that CS50 is an expensive course,” a representative from the university said, adding that its “per-student cost” is “more aligned” with other courses in the computer-science department, which are all much smaller. Because CS50 is also offered at the extension school, through Harvard’s Division of Continuing Education, it has a second source of funding; Leitner, who oversees the extension school’s innovation budget, told me that some of CS50’s spending is considered “R. & D.” Malan, who often employs up to a hundred teaching assistants, estimated that the “human side” of the cost alone amounts to at least two hundred thousand dollars a semester. For many of CS50’s extracurricular social events, he defrays expenses by asking tech companies to serve as sponsors.

Since Malan took over CS50, the total number of computer-science majors at Harvard has grown sixfold; according to data from the Computing Research Association, Harvard’s department grew fifty per cent more than the average university computer-science department between 2006 and 2015. (The percentage of women in the major has also increased, though only to about thirty per cent.) Lewis, the department’s pioneer, told me that the rise in interest has exposed CS50 to two separate kinds of criticism. On one side are hard-core computer-science students who assume, “because their roommates who don’t know anything” are taking CS50, that it’s “beneath them.” On the other side, Lewis continued, “There’s a set of people who are antipathetic, because it’s a symbol of technology taking over the world, the end of the liberal arts as the center of the university.” In 2014, for the first time, a university report revealed that more Harvard undergraduates majored in engineering and applied sciences than in the arts and humanities. In the past decade, the number of English majors at Harvard has declined by more than a third.

Leitner, who is sixty-six years old, with the scruffy look of an old-school programmer, spoke with obvious admiration of CS50, but he said that he has hesitated to approve some of the class’s expenditures. As Malan reminded me several times, he shoots CS50 in 4K high resolution, the standard for professional digital filmmaking, in order to achieve an experience “on par with what you would expect from Netflix.” He has written that the course’s high production value is “part of its pedagogy,” allowing students who tune in remotely to “feel no less a part of the classroom than students on campus.” But Malan adopted 4K resolution at a time, Leitner told me, when “people could barely stream regular high-def quality.” In 2016, Malan proposed using V.R. cameras—which cost more than twenty thousand dollars apiece—to allow CS50 students watching online to experience Sanders Theatre in 3-D. “Was it important? Was it worth the expense? I sort of joked with him that I didn’t see the pedagogical value,” Leitner said. (Malan told me that his proposal was conditional on getting Nokia, the cameras’ manufacturer, to lend them, which in the end it did.)

Malan equips Sanders Theatre, the stately lecture hall where he teaches, with five cameras—some manned by humans, others robotically controlled—and, at the back of the mezzanine, a makeshift production booth.

When he feels himself resisting Malan’s extravagance, Leitner often recalls that he had similar doubts about another bright, enterprising former student: Mark Zuckerberg, who took one of Leitner’s courses as a Harvard undergraduate, before dropping out, at the end of his sophomore year, to continue work on a Web site that he’d started from his dorm room. In 2004, at Zuckerberg’s invitation, Leitner created an account on TheFacebook.com, as it was then known, but he failed to grasp its extraordinary appeal. “I remember thinking, ‘Yeah, cute—big deal,’ ” Leitner said. A year later, the platform had more than five million users. “So I learned my lesson,” he added. “I think giving David freedom to innovate is really in everybody’s best interest. You never know what’s going to come out of it.”

On the first Monday in July, Harvard announced that its campus will reopen this fall to no more than forty per cent of undergraduates, including incoming freshmen and students deemed to be facing remote-learning challenges. For those both on and off campus, all learning will take place virtually. To Veneziano, a rising sophomore, the news was a shock. “I don’t think a lot of people were expecting the decision to be so strict,” he said. Yale would be allowing every class except the sophomores to return; many other colleges were reopening their campuses to their entire student bodies. Veneziano, who wasn’t likely to qualify for campus housing, was considering renting a cheap apartment in Boston with his freshman-year roommates, and perhaps taking a semester, or even a year, off. The ongoing spread of the coronavirus limited options for work and travel, and the school wasn’t guaranteeing that all students on leave would have housing when they returned. But Harvard’s tuition—more than forty-nine thousand dollars a year, excluding room and board—seemed harder to justify without the unquantifiable benefits of congregating around seminar tables, holing up in Gothic libraries, and cavorting in strangers’ dorms. Princeton had at least docked the cost by ten per cent; Harvard offered no reduction.

A few days after the plans were announced, Amanda Claybaugh, an English professor at Harvard who serves as the dean of undergraduate education, gathered a group of her colleagues on a Webinar, open to students, to discuss the fall semester. The spring had been a scramble, she said; now there was more time to plan. Some teachers were experimenting with ways to facilitate “serendipitous encounters” and “casual co-presence” virtually; in the spring, she explained, one art professor had left his video feed on as he painted, letting students tune in to work in quiet company. David Laibson, an economics professor, pointed out that, for all the difficulties of online learning, stay-at-home orders had allowed him to patch in guest speakers—Ben Bernanke, Timothy Geithner—who wouldn’t have been able to visit his class in person. Later, after he tried and failed to share his screen, Laibson urged his colleagues using Zoom to “Practice, practice, practice!” The next day, by phone, Claybaugh told me that all professors were expected to undergo a weeklong training program before teaching online in the fall. When I mentioned Malan’s return to film in Sanders Theatre, she seemed taken aback. If she so much as tried to fetch a book from her own office, she said, campus security dispatched a janitorial team after her.

The week of the announcement, Malan happened to be wrapping up his own educator workshop, which trains teachers all over the world to implement the tools and teachings of CS50. Though Malan serves on a number of committees at Harvard, I didn’t get the sense, from him or the administrators I spoke to, that he was especially active in planning for the school’s transition. In his free time, he published a post on Medium detailing his elaborate work-from-home station, which includes a 4K Webcam ($199), a wireless lavalier mike ($219), two fifty-three-inch L.E.D. bicolor baton stick lights (nearly $650 each), an eight-by-eight-foot wrinkle-free green screen ($399), and a standing-desk converter ($85.99), all installed in his kitchen. He wrote that, in a pinch, a cardboard box could serve as a substitute for a standing desk, and told me that he hoped such suggestions would help “make people feel more comfortable with the accessibility of it all.” Rebecca Nesson, a computer-science lecturer and associate dean, who is working with Claybaugh to plan for the fall, told me that, in the spring, Harvard had allotted up to a hundred and twenty-five dollars per instructor for equipment loans—in case anyone needed, say, a monitor to supplement her laptop screen. Malan’s recommendations were “out of the range of what Harvard could support,” she said.

The pandemic’s indefinite suspension of classroom learning has already forced universities nationwide to thin their faculty ranks in anticipation of lost revenue. It has also prompted speculation about the future of higher education. Harvard, which has an endowment of more than forty billion dollars, is likely to weather the upheaval. Will a handful of élite institutions grow dominant by expanding their online enrollment, while second-tier schools go under? If the pandemic leads colleges to embrace online coursework to a new degree, what will become of campus life as we know it? In 2015, when CS50 launched its partnership with Yale, many students and professors there voiced skepticism, fearing that importing Malan’s course would undermine Yale’s own computer-science department. Members of the department told me that CS50 has probably helped attract more students to computer science, but that its time at Yale has coincided with an increased reliance on untenured faculty. Zhong Shao, the chair of Yale’s computer-science department, told me that, because of the growth in enrollment, not all intro-level courses can be taught by “the existing number of tenure-track faculty alone.” The growth catalyzed by CS50, one professor told me, might have been achieved by developing an introductory course of comparable quality within the institution.

Malan sees it differently: it is wasteful, he said, to have thousands of teachers, in computer science or other fields, all doing the work of devising similar curricula. Good programmers spend much of their time “refactoring” software—editing it to reduce inefficiencies, or “code bloat.” Malan’s teaching method pursues a similar objective. “I don’t think we want just one introduction to computer science and one introduction to psychology or any such field,” he said. “But there’s probably a number around dozens—hundreds—that makes more sense?” Rather than threaten the livelihoods of professors or the independence of institutions, such consolidation would, Malan believes, free teachers to do their best work. And holding online courses to the same standards as in-person ones would allow students beyond the small, predominantly privileged groups who enroll in places like Harvard to access the highest-quality instruction.

Many fledgling computer programmers don’t bother getting college degrees at all. Gabriel Guimaraes, after teaching CS50 in Brazil for three years, applied and was admitted to Harvard. His acceptance was big news in the state of Espírito Santo; the week he received his acceptance letter, reporters showed up at his house. After graduating and going to work at a financial startup in San Francisco, though, Guimaraes discovered that a number of his colleagues—including his bosses—had dropped out of school. “You don’t need to go to Harvard,” he said recently, from a beach town outside Rio de Janeiro, where he is spending the pandemic with several co-workers. Malan, in one sense, shares the instinct to question who and what higher education is for: after all, the vast majority of the students who benefit from CS50 will never earn a Harvard degree. In another sense, though, Malan is the consummate Harvard traditionalist. He has spent nearly his entire adult life there, and he told me that he finds it hard to imagine leaving. “With so much free content out there,” he said, the name Harvard is what helps draw CS50 students in.

Malan has been brainstorming new tricks for bringing students into Sanders virtually in the fall. “You know how, at Logan Airport, they have that flight-attendant hologram thing?” he asked a dozen members of his staff on one call. “I don’t want that on the stage, but are there things like that?” Perhaps, one staffer suggested, they could fill the empty mezzanine with monitors and use Zoom’s gallery view to approximate a real audience? What if, Malan asked, they also projected the gallery view on screens behind him, allowing students watching the lectures to see their own faces? An undergraduate staffer on the call interrupted. “There is a risk they won’t turn their videos on,” he said, adding that, in one of his classes, only eight out of three hundred students did so. Malan wasn’t worried: the non-Harvard students could be counted on to keep their videos running. “They do seem to delight in becoming part of it—the fact that they got called on, or that they appeared onscreen, that kids are circling themselves and posting screenshots to Instagram,” he said. “Making them part of it feels like a new opportunity.”

Eren Orbey