by Salman Khan
There’s an old saying that life is school. If that’s true, then it’s also true that as our world grows smaller and the people in it more inextricably connected, the world itself comes to resemble one vast, inclusive schoolhouse. There are younger people and older people, people farther or less far along in their education on a given subject. At every moment, we are both students and teachers; we learn by studying, but we also learn by helping others, by sharing and explaining what we know.
I like to think of Khan Academy as a virtual extension of this One World Schoolhouse. It’s a place where all are welcome, all are invited to teach as well as learn, and all are encouraged to do the best they can. Success is self-defined; the only failure lies in giving up. Speaking for myself, I have learned as much from the Academy as I have taught. I have gotten back—in intellectual pleasure, refreshed curiosity, and a sense of connection to other minds and other people—more than I have put in. It’s my hope that every Academy student and every reader of this book will be able to say the same.
PART 1
Learning to Teach
Teaching Nadia
There is an art, or rather, a knack to flying. The knack lies in learning how to throw yourself at the ground and miss. Pick a nice day and try it.
—DOUGLAS ADAMS, THE HITCHHIKER’S GUIDE TO THE GALAXY
This story starts with one student and one teacher. It begins as a family story, so let me tell you a bit about my background.
I was born in Metairie, Louisiana, a residential area within metro New Orleans. My father, a pediatrician, had moved there from Bangladesh for his medical residency at LSU and, later, his practice at Charity Hospital. In 1972, he briefly returned to Bangladesh and came back with my mother—who was born in India. It was an arranged marriage, very traditional (my mother tried to peek during the ceremony to make sure she was marrying the brother she thought she was). Over the next several years, five of my mother’s brothers and one cousin came to visit, and they all fell in love with the New Orleans area. I believe that they did this because Louisiana was as close to South Asia as the United States could get; it had spicy food, humidity, giant cockroaches, and a corrupt government. We were a close family—even though, at any given moment, half of my relatives weren’t speaking to the other half.
Still, a family wedding was a big occasion, so when I got married in 2004, more than forty relatives made the long trip to New Jersey, where my wife’s family lived. One of them was my cousin Nadia.
Today, Nadia is a pre-med junior at Sarah Lawrence College. But in 2004 she was a very serious-minded twelve-year-old who had just had the first academic setback of her life. She’d done poorly on a math placement exam given at the end of sixth grade. She was a straight-A student, highly motivated, always prepared. Her subpar performance baffled her. It wounded her pride, her confidence, and her self-esteem.
By the time we spoke after my wedding, Nadia had actually come to accept the outcome of that test. She believed that she just wasn’t good at math. I saw it very differently. I saw real potential in her. She was logical, creative, and tenacious. I was already viewing her as a future computer scientist or mathematician. It seemed inconceivable to me that she, of all people, would find something in the sixth grade difficult.
Having gone through the traditional academic system, it was also clear to me that being placed in the slower math class could be the kiss of death for her mathematical future. Because of “tracking”—a subject we’ll have occasion to come back to—this one test result would have huge ramifications for Nadia’s academic destiny. If she didn’t get into the more advanced track, she wouldn’t be able to take algebra in eighth grade. If she didn’t take algebra in eighth grade, she wouldn’t be able to take calculus in twelfth. And so on, down a slippery slope that would leave her far short of her potential.
But a botched test was a botched test. Was there anything to be done about it? Nadia’s mother didn’t think so, and during a post-wedding visit to Boston, where I lived and worked, it became clear that she was very distressed. So I made a somewhat rash offer. If Nadia’s school would let her retake the exam, I would tutor her, remotely, when she was back in New Orleans. As to exactly how I would tutor her… well, that was a work in progress.
Let me be clear—I think it’s essential for everything that follows—that at the start this was all an experiment, an improvisation. I’d had no teacher training, no Big Idea for the most effective way to teach. I did feel that I understood math intuitively and holistically, but this was no guarantee that I’d be effective as a teacher. I’d had plenty of professors who knew their subject cold but simply weren’t very good at sharing what they knew. I believed, and still believe, that teaching is a separate skill—in fact, an art that is creative, intuitive, and highly personal.
But it isn’t only an art. It has, or should have, some of the rigor of science as well. I felt that I could experiment with different techniques to see what worked and what didn’t, that with time I could develop myself into an effective tutor for Nadia. It was an intellectual challenge not too different from those I faced in the investing or technology worlds, but this one had the very real potential to empower someone I cared about.
I had no preconceived notions about how people learned; I was constrained by no orthodoxy regarding the “right” way to do things. I was feeling my way for how best to convey information and to employ the available technology. In short, I was starting from square one, without habits or assumptions. It’s not just that I was thinking outside the box; for me, there was no box. I tried things and I saw what worked. By extension, I also inferred what hadn’t been working.
Actually, I did bring a few assumptions into my approach to working with Nadia, though they were based on personal experience rather than on any sort of pedagogic theory. During my own school years I’d felt that some teachers were more interested in showing off what they knew than in communicating it to me. Their tone was often impatient, occasionally arrogant and even condescending. Other teachers were scripted to the point that it didn’t feel like they were actually even thinking. I wanted our tutorial sessions to be a safe, personal, comfortable, thought-provoking experience. I wanted to be a tutor who genuinely shared his thinking and expressed it in a conversational style, as if I was speaking to an equal who was fundamentally smart but just didn’t fully understand the material at hand.
I firmly believed that Nadia, and most people, could understand the math. I didn’t want her to memorize and I certainly didn’t want her to compartmentalize. I was convinced that if she understood the conceptual underpinnings of mathematics, the flow of one idea to the next, everything else would be easy.
In any case, the first step in tutoring Nadia was to figure out what aspect of the math test had given her trouble. It turned out that she had stumbled on the concept of unit conversion. This surprised me. Unit conversion—figuring out how many feet in six miles, or how many ounces in three pints, and so forth—was a fairly straightforward notion. You learned a few terms—kilo for a thousand, centi for a hundredth—and the rest of the factors you could easily look up. From there it was a simple matter of multiplication or division. Nadia had done just fine with far subtler concepts in math.
So why did she have trouble with unit conversion? She didn’t know, and neither did I. But let’s think about a few of the possible reasons that she might not have “gotten” this particular topic.
Maybe she was absent on the day it was introduced in class. Maybe she was physically present but not at her best. Maybe she was sleepy, or had a bellyache, or was upset about an argument with her mom. Maybe she had an exam in the class that came next, and was cramming for that instead of paying attention. Maybe she had a crush on a boy two rows over and was daydreaming about him. Maybe her teacher was in a hurry to move on and just didn’t explain it very well.
These are only conjectures; the point is that there are any number of things that might have prevented Nadia from catching on to unit conversion, an
d that once the concept had passed her by, it wasn’t coming back in class. That module had been covered. Those problems had been worked on and erased. There was a curriculum to follow, a schedule to keep; the class had to move on.
Let’s take a moment to consider this. It so happened that Nadia attended a fine prep school, with an excellent student/teacher ratio and quite small class sizes. Class size, of course, is an obsession among those who believe that our standard educational model would work just fine if only we could afford more teachers, more buildings, more textbooks, more computers—more of everything except students, so that class sizes could be reduced (essentially making poor schools look more like rich ones). Now, no one is against the idea of smaller classes; I want as low of a ratio as economically possible for my own children so they have time to really form bonds with their teachers. Unfortunately, however, the idea that smaller classes alone will magically solve the problem of students being left behind is a fallacy.
It ignores several basic facts about how people actually learn. People learn at different rates. Some people seem to catch on to things in quick bursts of intuition; others grunt and grind their way toward comprehension. Quicker isn’t necessarily smarter and slower definitely isn’t dumber. Further, catching on quickly isn’t the same as understanding thoroughly. So the pace of learning is a question of style, not relative intelligence. The tortoise may very well end up with more knowledge—more useful, lasting knowledge—than the hare.
Moreover, a student who is slow at learning arithmetic may be off the charts when it comes to the abstract creativity needed in higher mathematics. The point is that whether there are ten or twenty or fifty kids in a class, there will be disparities in their grasp of a topic at any given time. Even a one-to-one ratio is not ideal if the teacher feels forced to march the student along at a state-mandated pace, regardless of how well the concepts are understood. When that rather arbitrary “snapshot” moment comes along—when it’s time to wrap up the module, give the exam, and move on—there will still likely be some students who haven’t quite figured things out.
They could probably figure things out eventually—but that’s exactly the problem. The standard classroom model doesn’t really allow for eventual understanding. The class—of whatever size—has moved on.
In muddling toward my own approach to tutoring, then—in trying to match my methods to how I thought people really learn—two of my first precepts were these: that lessons should be paced to the individual student’s needs, not to some arbitrary calendar; and that basic concepts needed to be deeply understood if students were to succeed at mastering more advanced ones.
But let’s come back to Nadia.
She returned to school in New Orleans. I resumed my working life in Boston. I’d equipped us both with inexpensive pen tablets that would allow us to see each other’s scrawls on our respective computers, using a program called Yahoo Doodle. We scheduled sessions to talk on the phone and figure out this troublesome business of unit conversion.
The first week of tutoring was pure torture—torture for me, and I’m guessing it was ten times worse for her. But it taught me, in a very immediate and intimate manner, about some of the many complicating factors that get in the way of learning.
There was no doubt that Nadia was extremely bright. When she and her family had visited me in Boston, we’d killed some time by working on a battery of brain teasers while waiting for the Fourth of July fireworks to start over the Charles River. What I most remembered was how willing Nadia was to tackle hard problems. How analytical and creative she was. How she was able to logically break down questions that I’ve seen interviewees from top engineering and business schools struggle with. Yet when it came to unit conversion, her brain just seemed to shut down. It froze; it locked. Why? It seemed to me that she’d just plain psyched herself out. Like many people who’d had difficulty with a particular subject, she’d told herself she’d never get it, and that was that.
I told her, “Nadia, you’ve mastered much harder things than this. You’ll get this, too.”
Either she didn’t hear me or she thought I was lying to her. We started doing problems. I’d ask a question. There’d be a silence—a silence that went on so long I sometimes thought we’d lost the telephone or Internet connection. Finally her answer would come, meekly, with her voice turning up at the end. “A thousand?”
“Nadia, are you guessing?”
“A hundred?”
I was starting to get seriously concerned that perhaps I was doing Nadia more harm than good. With nothing but kind intentions, I was causing her a lot of discomfort and anxiety. My hope had been to restore her confidence; maybe I was damaging it still further.
This forced me to acknowledge that sometimes the presence of a teacher—either in the room or at the other end of a telephone connection; either in a class of thirty or tutoring one-to-one—can be a source of student thought-paralysis. From the teacher’s perspective, what’s going on is a helping relationship; but from the student’s point of view, it’s difficult if not impossible to avoid an element of confrontation. A question is asked; an answer is expected immediately; that brings pressure. The student doesn’t want to disappoint the teacher. She fears she will be judged. And all these factors interfere with the student’s ability to fully concentrate on the matter at hand. Even more, students are embarrassed to communicate what they do and do not understand.
With that in mind—and partly out of sheer exasperation—I tried a somewhat different strategy. I said, “Nadia, I know you’re smart. I’m not judging you. But we’re changing the rules here. You’re not allowed to guess, and you’re not allowed to give me wishy-washy answers. There are only two things I want to hear. Either give me a definite, confident answer—yell it out!—or say, ‘Sal, I don’t understand. Please go over it again.’ You don’t have to get it the first time. I won’t think less of you for asking questions or wanting something repeated. Okay?” I think it might have pissed her off a bit, but it had the right effect. She began decisively, and somewhat angrily, to shout answers—or admissions of lack of understanding—back at me.
Very soon after that, Nadia seemed to have one of those Aha moments. Unit conversion rather suddenly started making sense and the tutoring sessions became a lot of fun. Which came first, the success or the enjoyment? I don’t really know, and I don’t think it matters. What does matter is that along with her growing comfort with the subject, Nadia’s confidence and alertness came roaring back. I could hear her pleasure when she knew an answer. More important, there was no embarrassment or shame when she needed something explained again—when she hit the replay button, so to speak.
There was also another aspect to Nadia’s changed mood. Once she started understanding unit conversion, she was angry that she hadn’t gotten it before. It was a healthy, useful kind of anger. She was mad at herself for feeling daunted, for doubting her own abilities, for having given in to discouragement. Now that she’d conquered one recalcitrant subject, she’d be much less likely to let herself be daunted ever again.
Nadia went on to retake her math exam, and passed with flying colors. In the meantime, I had also started tutoring her younger brothers, Arman and Ali. Word got out to a few other family members and friends, and before long I had around ten students. Though I didn’t realize it at the time, the Khan Academy was mysteriously coming into being—was being pulled into being by the curiosity and needs of its students and their families. The invisible process of its going somewhat viral was already in the first tiny stage of gathering momentum.
All of my tutees, I’m proud to say, were soon doing work way beyond their grade levels—and I was hooked on teaching. I couldn’t help comparing the substance and satisfaction of my tutoring work to the money-based routines of my day job at the hedge fund. Now, I definitely don’t agree with the knee-jerk opinion that hedge funds are evil; the majority of the people in the field are actually highly intellectual, good people. Still, the focus of a workday in i
nvesting is not exactly social service. Was that really how I wanted to spend my life? Was that really the best use of my limited time on Earth?
I was in a bind. I was stuck in a job I really liked—it was challenging and intellectually and financially rewarding. But I had a nagging feeling that I was being held back from a calling I saw as far more worthwhile.
So I kept the day job and saved my pennies, looking forward to the time when I could afford to quit. In the meantime, I started experimenting with various techniques that might make me more efficient in serving my growing roster of tutees; again, I took a problem-solving, nuts-and-bolts approach to this—an engineer’s approach.
I tried to schedule Skype sessions with three or four students at a time. The logistics were unwieldy, and the lessons themselves not as effective as working one-to-one. To help automate things, I wrote some software that would generate questions and keep track of how each student did with the responses. I enjoyed writing the program, and it did give me valuable insights into where I should focus the time during the live sessions. As we will see later in our story, these techniques for gathering, organizing, and interpreting data have by now become useful and sophisticated tools. The software by itself, however, didn’t solve the problem of making the live sessions more scalable.
Then, just when I was starting to feel that I’d taken on too much and should probably back away, a friend came up with a suggestion: Why didn’t I record the lessons and post them on YouTube, so that each student could watch them at his or her convenience?