by Jonah Lehrer
One of the reasons self-explanation works is because it forces people to acknowledge the mystery. A recent study by physicists at Harvard looked at the impact of the method among college students in an introductory physics class.9 In the control condition, students were given a standard chalkboard lecture—“the sage on a stage” method—and were explicitly told how to solve the sample problems. In the self-explanation condition, the students were given the exact same information and handouts but had to solve the problems by themselves in small groups. As expected, students in the self-explanation condition scored significantly higher on a subsequent test of learning. They understood the physics material better.
But these educational benefits come with a twist: the students thought they learned less. What accounts for this discrepancy? Because the students had to solve the problems on their own, they became “painfully aware of their lack of understanding, in contrast with fluent lectures that may serve to confirm students’ inaccurately inflated perceptions of their own abilities.” Self-explanation forced them to acknowledge the mystery, all those slippery concepts they still didn’t understand. And that’s why they learned so much more.
Unfortunately, the typical American classroom is often designed to make learning as easy as possible, which minimizes self-explanation. That, at least, is the conclusion of the TIMSS study, which has been gathering data on the teaching of math and science across the world since 1995. After filming hundreds of classrooms in seven countries in the late ’90s, it became clear that American students were usually given simple rules to solve their math problems, or what the researchers described as lessons built around the “use of procedures.” (This is what Lauren dismisses as the “plug and chug” method.) According to the data, 55 percent of American eighth-grade math lessons featured the use of procedures; in another 36 percent the teacher gave away the answer without any additional explanation. Less than 10 percent of all lessons tasked students with any sort of self-explanation.
Imagine getting the following problem in math class: you have to draw and define an isosceles right triangle, or a triangle with one ninety-degree angle and two legs that are equal in length. In the American classrooms, the teachers would usually just draw the triangle—this is what it looks like. They might also give the students a straightforward rule for getting the answer. (“Draw two congruent legs and connect them with a right angle.”) Such an approach makes the lesson easy. There is no ambiguity, just the efficient delivery of answers.
The downside is that the ease minimizes long-term learning. According to more recent TIMSS results, Japanese students are consistently some of the highest performers on math and science tests in the world. (Only Singapore, Taiwan, and South Korea can compete.)10 One explanation for the success of Japanese students is the strategies employed by their teachers. When the TIMSS researchers cataloged their classroom time, they found that less than 3 percent of Japanese lessons involved plug and chug or teachers delivering the answers. Instead, their lessons were built around “making connections.” While American teachers drew the isosceles right triangle for their students, the Japanese teachers would focus on more fundamental concepts, such as the properties shared by all these triangles, or the meaning of Pythagoras’s constant.11 The eighth graders weren’t shown the solution, or even a set of procedures for finding the solution. They were given a problem that they had to solve for themselves. “Part of the reason US students don’t do as well on international measures of high school knowledge is that they’re doing too well in class,” said the cognitive psychologist Nate Kornell, in an interview with David Epstein. “What you want is to make it easy to make it hard.”12I
Later in the day, I sit down with Danny, that student who bombed the SAT because he couldn’t let go of a hard problem. Danny has a mop of unruly curls, a delicate face, and large doe eyes; he speaks quietly, but with the assurance of a teenager used to sharing his thoughts. After college, he wants to be a band teacher. I ask Danny why he thinks the Harkness method leads to such a dramatic boost in test scores. “When you go to a school that teaches to the test, it gets pretty boring because it’s just about remembering this or that,” he says. “But here you can really dive deep into stuff, and then you get to hear what everyone else thinks, too. It’s more work, I guess, but you don’t really mind because it’s not boring.”
The lack of boredom became a consistent theme in my conversations with the students. For them, there was nothing counterintuitive about the success of Harkness at the Noble Academy. Simply put, the high-risk, high-ambiguity method worked because it made their education more interesting. “If you are immune to boredom, there is literally nothing you cannot accomplish,” writes David Foster Wallace. “It is the key to modern life.”13
Erin Westgate, a psychologist at the University of Florida, has devoted her career to studying the causes of boredom. She defines boredom as an emotion that “alerts us that we are unable or unwilling to successfully engage attention in meaningful activities.”14 The key word in that definition is meaningful. Too often, schools take the meaning of their activities for granted. They assume that students are motivated by grades or test scores or the thrill of understanding quadratic equations. The Harkness approach, however, encourages students to find their own meaning in the curriculum. They control the conversation. They choose the topics. And what they usually end up talking about is the mystery, the material that incites the most debate and disagreement. It might be surprising, but it’s not the settled answers that give us meaning. It’s the questions. Not knowing is the antidote to boredom.
A senior named Gloria—she wants to major in premed or public policy—described her own transition at the academy: “At first, I didn’t really like it here. I was like, ‘I’m not even learning anything because all we do is talk about what we don’t understand.’ But then, as you do it, you realize that’s the best way to learn.… If you’re just told what a book is about, then you’re going to forget it. But if you read the book and you have to decide for yourself what it’s saying, and you get to hear what all your friends think, then you’re going to pay attention.” Gloria laughs, flashing her braces. “Because sometimes what your friends say is totally insane. I’m like, ‘Did we even read the same book? How could you possibly think that?’ And then they explain and it makes you rethink what you thought.”
Not until the end of the school day, as the students are getting ready to leave, do I notice the inscription on the back of their sweatshirts. It’s the slogan of the Noble Academy, a mantra repeated every day in every classroom: Take Risks. No Fear. No Shame.
Knowing What You Don’t
When Aida Conroy was in eighth grade, she was awarded a full scholarship to Exeter. She’d attended public schools in Rogers Park, on the far north side of Chicago, and wasn’t prepared for the transition. “I grew up just like the kids here [at the Noble Academy],” Aida says. “I thought Exeter would basically be Harry Potter. You learn some spells, become a wizard, stuff like that.” The reality was far less romantic. Aida was too scared to talk in class. She cried herself to sleep for weeks. “It took me a while to even understand what was expected of me in the Harkness conversations,” she remembers. “But over time it became this life-changing experience.”
Aida is a Harkness mentor at the Noble Academy. She has a youthful face and an incandescent smile; if she were wearing the academy uniform, and not a bright orange blouse, she could easily pass for a student. Although Aida still teaches, her main focus is on supporting her fellow instructors, sitting in on their classes and offering them advice and feedback. “When you’re used to standing up at the front of class and performing for fifty minutes, it can be a pretty big change to Harknessing,” she says. “It can feel like you’re giving up all control.” Aida laughs. “Actually, you are giving up all control.”
That lack of control often means that teachers have to spend additional time on class preparation, since they never know how the conversation will unfold. “There’s n
o script,” Aida says. “Because you’re giving the students open-ended prompts, you really have to be prepared for a wide range of possible discussions. It almost never goes how you think it will go.”
To deal with this uncertainty, Aida gives Harkness teachers a new set of techniques for interacting with their students. Aida offers the example of the awkward silence. “Sometimes the students are in conversation and there’s a long pause. And when you’re new to Harkness, it’s easy to react and interrupt because you think nothing’s happening. But kids have to get comfortable with silence. Sometimes you need that silence to think. That’s why I always say it’s not an awkward silence—it’s a pregnant pause. Something good is going to come out of it.”
There were plenty of those pregnant pauses in Becky Wessels’s World History class. Becky is another Harkness mentor, and her classroom walls are decorated with suggested conversation prompts for the students, such as “I’d like to complicate that…” or “I would suggest a different way of looking at it…” or “I’m not entirely convinced that…” The students are talking about the trade-offs of empire—the prompts covered the conquests of Rome—and many of their sentences begin with gentle forms of dissent. They disagree with a smile.
Toward the end of class, Ms. Wessels encourages the students to get introspective. They stop talking about ancient Rome and start dissecting their own conversation. Lauren had told me earlier that such self-reflection was one of the key transitions for Noble students. “It’s this very meta-moment,” she said. “But it’s also very important because it means they’re taking responsibility for their learning. They realize that a good discussion isn’t about the teacher or the content. It’s up to them.” In Ms. Wessels’s history class, one student said they should have used more evidence from the text; another noted that it was hard talking about religion; a boy who stayed quiet during class said he should have asked some follow-up questions.
What struck me about these meta-conversations was the way they captured the essential culture of the Noble Academy. These students have learned that learning is a process, not something handed down by a grown-up. They critique their own conversations because their entire education is a conversation, a shared struggle to find new and better questions to ask each other. Noble Academy students don’t walk into the classroom and expect to leave seventy-four minutes later with a notebook full of answers. They walk into the classroom and expect to learn that there are other ways of solving math problems and reading the Constitution and thinking about the world.
When I asked Aida Conroy whether the high test scores of academy students surprised her, she responded by highlighting the limits of the typical No Excuses public school approach: “I have seventy-four instructional minutes a day to teach students that entered high school reading at a sixth-grade level. I could do blatant reading instruction for the whole year and probably make up about two years of growth. Most educators would say that’s a success. But I don’t think I’d be instilling in them any love and joy of learning if I did that. And the thing about the love and joy of learning, as cheesy as it sounds, is that it transfers. With Harkness, by the end of the year my kids are sending me articles that they want to read in class. They’re bringing up issues and problems that I never thought of. They’re learning from each other. And so that seventy-four minutes is expanded, because now they have a better sense of what they don’t know. And that becomes what they’re most interested in.”
What Aida is describing is intellectual humility, a character strength that shapes how we learn and respond to new information. According to the research, those with high levels of intellectual humility are more likely to admit they’re wrong or don’t understand something. They’re also better at seeking out new information that contradicts their beliefs.15 Instead of embracing certainty, they enjoy the difficult delights of mystery.16 “A lot of what schools call ‘critical thinking’ comes down to intellectual humility: knowing what you don’t know,” notes Angela Duckworth, a psychologist at the University of Pennsylvania.17 It’s an ironic fact of education, but perhaps the most important lesson we learn is the limits of our education.
Intellectual humility isn’t on the Illinois state curriculum, and it’s not on any standardized test, but it’s an essential part of the Noble Academy education. Here on the edge of Cabrini-Green, amid the empty lots and stucco strip malls, these students are learning how to get excited by mystery. They’re being trained to seek out hard problems and ambiguous content. Their teachers are celebrating curiosity, even if it leads to the incorrect answer. “The best part for me is when the students are leaving the classroom, walking out the door, and they’re still talking about what was discussed at the Harkness table,” Aida says. “Because that’s when you know it’s working. They’re applying this way of thinking, of learning, and using it everywhere. It’s not just something they do at school. It’s become part of their life.”
I. There’s a parallel here with social media, and the way it makes it easy for us to overestimate our knowledge, just like those students in typical American classrooms. Facebook is a primary news source for more than 40 percent of Americans. Why is Facebook so popular? Much of the credit belongs to the algorithm that personalizes the News Feed, delivering a unique stream of content to every user. Here’s the dismal twist: the software has learned that an efficient way to keep our attention is to serve up content that confirms what we already believe. If you make people feel secure in their opinions, if you filter out the complexity and dissent, they end up spending more time on the social network. The problem is that this leads people to have faith in false beliefs.
CODA: THE MECHANIC AS DETECTIVE
Doubt is one of the names of intelligence.
—JORGE LUIS BORGES
The Porsche 911 came into the repair shop with a strange problem—the engine wouldn’t turn off. Jeff Haugland, co-owner of EuroSpec Motoring, one of the best Porsche specialists in Los Angeles, had dealt with thousands of mechanical issues on these expensive sports cars but he’d never seen a failure like this one. “You would turn the key, take it out, but the engine would keep running,” Jeff says. “Do it again, and again, but the engine just would not shut off.”1 Jeff could only stop the engine by starving it of air. “I had to cover the air intake with my bare hands. Like I was strangling it.”
This Porsche had a devastating malfunction—a car that won’t turn off is inoperable. (The owner had been letting it run until it ran out of gas.) Yet the car itself gave no sign anything was wrong—there were no warning lights, no error codes, no beeps or alerts. “A modern car has dozens of computers that control everything from the fuel injection to the exhaust,” Jeff says. “And if anything is outside the parameters”—if, say, the engine is running a few degrees too hot—“then you get that service light telling you to take it in.”
The problem with the Porsche that wouldn’t turn off, however, was that its computers thought the car was running perfectly. “The computers have to be programmed to detect the problems,” Jeff says. “And nobody ever thought to program an error code for an engine that wouldn’t stop. I mean, that’s insane.”
Jeff looks like a mechanic out of central casting: gray Dickies, neck tattoos, backward baseball hat, grease marks on his hands and cheeks. When I arrive at EuroSpec, he’s still underneath an old Porsche, banging away at a rusted joint. I pass the time by admiring the contradictions of twenty-first-century car repair. One side of the shop features the traditional tools of the mechanic—greasy lube tubes, wrenches and sockets in every shape and size, stacks of motor oil. But there’s also a wall of digital tablets—black mirrors with dirty fingerprints—that give Jeff and his team access to the hidden guts of these incredibly sophisticated machines.
“In the old days, everything was analog,” Jeff says. “You pressed on the gas, your foot causes a hole to open, more fuel is squirted into the engine. Now you press on the gas, you move your foot this much”—Jeff holds his fingers an inch apart—“and the
electronic sensor tells the computer you want sixty-two percent throttle. So instead of the fuel injectors pulsing at 1.3 milliseconds, they’re going to pulse at 1.8 milliseconds. The point is that your little movement is being translated by a bunch of computers into extremely precise instructions to the engine.” Jeff sighs, as if he misses the analog days. “That precision leads to much better performance, but the trade-off is that there’s a lot of shit that can break. And none of it is cheap.”
In many respects, the rise of computers has diminished the mystery of car repair. Mechanics used to be detectives in the mold of Sherlock Holmes, or Tom and Ray Magliozzi from Car Talk. A customer would enter the shop with a vague complaint: perhaps the car was making a strange noise at cold idle, or the steering column would vibrate during left turns at slow speed. The job of the mechanic was to translate these mysterious symptoms into a diagnosis, identifying the bits of broken metal and rubber responsible for the problem.
But the modern car can now diagnose itself, sharing its error codes and malfunctions. It reports broken circuits, out-of-sync pistons, and takes its own temperature every few seconds. “You always begin with the computer,” Jeff says. “A car comes in the shop, first thing you do is plug it in, let it tell you what it thinks is wrong.” But as Jeff points out, these computer diagnoses are the start of the deductive process, not the end. Consider a common problem for Porsches, which is an error involving the ignition coils. “A crappy mechanic will see that error code and just put in a new coil,” Jeff observes. They treat the computer as an oracle; there is no mystery, since the computer has already told them what’s wrong.