by Robin Hanson
Even more troubling for the “learning” story, however, is the fact that even when useful material is taught, students don’t retain it long enough to apply it later in life. They may cram well enough to pass their final exams, but if they’re given the same exam years later, they won’t do much better than students who never took the class. For example, while most high school students must take two years of a foreign language, less than 7 percent of adults report that they can speak a foreign language better than “poorly” as a result of schooling (and less than 3 percent can speak it “well”). In general surveys, only 38 percent of American adults can pass the U.S. citizenship test, only 32 percent know that atoms are bigger than electrons, and barely half can compute that saving $0.05 per gallon on 140 gallons of oil yields $7.00 of savings. And yet, at some point, these were basic facts and skills that almost everyone learned.
Furthermore, even if we could remember what we learn in school, decades of research have shown that we’re bad at transferring our knowledge to the real world. In school, when a teacher lectures on a sample problem, and then assigns a modestly different homework problem, most students can figure out how the homework is like the lecture. But decades later, almost no one can reliably recognize a complex real-world problem as similar enough to a school problem to successfully apply school learning.
School advocates often argue that school teaches students “how to learn” or “how to think critically.” But these claims, while comforting, don’t stand up to scrutiny. “Educational psychologists,” writes Caplan, “have measured the hidden intellectual benefits of education for over a century. Their chief discovery is that education is narrow. As a rule, students only learn the material you specifically teach them.”6
Another systems-level failure is that schools consistently fail to use better teaching methods, even methods that have been known for decades. For example, students learn worse when they’re graded, especially when graded on a curve.7 Homework helps students learn in math, but not in science, English, or history.8 And practice that’s spaced out, varied, and interleaved with other learning produces more versatility, longer retention, and better mastery. While this feels slower and harder, it works better.9 Instead, most schools grade students frequently (often on curves), give homework, and lump material together in ways that make it feel like students are learning faster, when in fact they’re learning less.
Students, especially teenagers, also learn more in school when classes don’t start so early.10 In a North Carolina school district, a one-hour delay in school start time—for example, from 7:30 a.m. to 8:30 a.m.—resulted in a 2 percentile gain in student performance.11 And yet most school districts, at least in the United States, start school earlier for teenagers than for preteens.12
Perhaps the most damning puzzle of all, however, is the finding that education isn’t nearly as valuable at the national level as at the individual level. The data are a little messy, but here’s how it works. Individual students can expect their incomes to rise roughly 8 to 12 percent for each additional year of school they complete. Nations, however, can expect their incomes to rise by only 1 to 3 percent for each additional year of school completed by their citizens on average.13 If schooling actually works by improving individual students, then we would expect the improvements for individual students to be cumulative across a nation. But nations don’t seem to benefit as much from educating their citizens. Something, as they say, doesn’t add up.
A SIGNALING EXPLANATION
In 2001, the Nobel Prize was awarded to economist Michael Spence for a mathematical model of one explanation for these puzzles: signaling.14 The basic idea is that students go to school not so much to learn useful job skills as to show off their work potential to future employers. In other words, the value of education isn’t just about learning; it’s also about credentialing. Of course, this idea is much older than Spence; he’s just famous for expressing the idea in math.
In the signaling model, each student has a hidden quality—future work productivity—that prospective employers are eager to know.15 But this quality isn’t something that can be observed easily over a short period, for example, by giving job applicants a simple test. So instead, employers use school performance as a proxy. This works because students who do better in school, over the long run, tend to have greater work potential. It’s not a perfect correlation, of course, and there are many exceptions, but by and large, school performance predicts future work performance (and therefore earnings).
People often talk as if intelligence were the key element underlying both school and work performance. But ordinary IQ can’t be the whole story, because we have cheap and fast tests to reveal IQ. More to the point, however, raw intelligence can only take you so far. If you’re smart but lazy, for example, your intelligence won’t be worth very much to your employer. As Caplan argues, the best employees have a whole bundle of attributes—including intelligence, of course, but also conscientiousness, attention to detail, a strong work ethic, and a willingness to conform to expectations. These qualities are just as useful in blue-collar settings like warehouses and factories as they are in white-collar settings like design studios and cubicle farms. But whereas someone’s IQ can be measured with a simple 30-minute test, most of these other qualities can only be demonstrated by consistent performance over long periods of time.
Imagine interviewing a 22-year-old college grad for a position at your firm. Glancing down at her resume, you notice she got an A in the biology class she took during her sophomore year. What does this tell you about the young woman in front of you? Well, it doesn’t necessarily mean she understands biology; she might have retained that knowledge, but statistically speaking, she’s probably forgotten a lot of it. More precisely, it tells you that she’s the kind of person who’s capable of getting an A in a biology class. This is more than just a tautology. It implies that she has the ability to master a large body of new concepts, quickly and thoroughly enough to meet the standards of an expert in the field—or at least well enough to beat most of her peers at the same task. (Even if the class wasn’t graded on a strict curve, most professors calibrate their courses so that only a minority of students earn A’s.) In addition to what the A tells you about her facility with concepts, it also tells you that she’s the kind of person who can consistently stay on top of her workload. Every paper, project, and homework assignment has a deadline, and she met most if not all of them. Every test fell on a specific date, and she studied and crammed enough to perform well on those tests—all while managing a much larger workload from other classes, of course. If she got good grades in those courses too—wow! And if she did lots of extracurricular activities (or a small number at a very high level), her good grades shine even brighter. All of this testifies quite strongly to her ability to get things done at your firm, and none it depends on whether she actually remembers anything from biology or any of her other classes.16
In other words, educated workers are generally better workers, but not necessarily because school made them better. Instead, a lot of the value of education lies in giving students a chance to advertise the attractive qualities they already have.
Caplan offers a helpful analogy. Suppose you inherit a diamond from your grandma, and you want to turn around and sell it. What can you do to fetch a good price? On the one hand, you could take steps to improve the diamond, perhaps by polishing it or cutting it into a more attractive shape. On the other hand, you could take the diamond to be inspected by a professional, who will then issue a certificate attesting to its quality. This will also raise the price, since most buyers can’t judge a diamond themselves, and without a certificate, they’re worried about getting swindled.
The traditional view of education is that it raises a student’s value via improvement—by taking in rough, raw material and making it more attractive by reshaping and polishing it. The signaling model says that education raises a student’s value via certification—by taking an unknown specimen, subjecti
ng it to tests and measurements, and then issuing a grade that makes its value clear to buyers.
Of course, these two processes aren’t mutually exclusive. While labor economists tend to downplay the signaling model, it’s well known as an explanation and is popular among sociologists of education. No one claims that signaling explains the entire value of education. Some learning and improvement certainly does take place in the classroom, and some of it is critical to employers. This is especially true for technical and professional fields like engineering, medicine, and law. But even in those fields, signaling is important, and for many other fields, signaling may completely eclipse the learning function. Caplan, for example, estimates that signaling is responsible for up to 80 percent of the total value of education.
IMPLICATIONS OF THE SIGNALING MODEL
“I have never let my schooling interfere with my education.”—Mark Twain17
The signaling model can explain all the puzzles we saw earlier. Clearly it explains why both students and employers are more interested in credentials (getting good grades and degrees from good colleges) than learning per se, even though, like Robin, they could get top-quality learning entirely for free. It also explains why no one is particularly bothered when curricula are impractical or when students forget what they learn—because it’s not the knowledge itself that’s as important as showing that you have the generic ability to learn and complete schoolwork. Signaling also explains the sheepskin effect, where actually earning a diploma is more valuable than the individual years of learning that went into it—because employers prefer workers who stick around and finish what they start.
As is often the case with these “hidden motive” explanations, things that seem like flaws (given the official function) actually turn out to be features (for the hidden function). For example, the fact that school is boring, arduous, and full of busywork might hinder students’ ability to learn. But to the extent that school is primarily about credentialing, its goal is to separate the wheat (good future worker bees) from the chaff (slackers, daydreamers, etc.). And if school were easy or fun, it wouldn’t serve this function very well. If there were a way to fast-forward all the learning (and retention) that actually takes place in school—for example, by giving students a magic pill that taught them everything in an instant—we would still need to subject them to boring lectures and nitpicky tests in order to credential them.
Signaling also explains a lot of things we don’t see (that we might expect to see if school were primarily about learning). For example, if the value of a college degree were largely a function of what you learned during your college career, we might expect colleges to experiment with giving students a comprehensive “exit exam” covering material in all the courses they took. Sure, it would be difficult, and there’s no way to test the material in the same depth as final exams given at the end of each semester. But if employers actually cared about knowledge, they’d want to know how much students actually retain. Instead, employers seem content with information about students’ generic ability to learn things (and complete assignments on time).
Remember the puzzle where nations don’t get as much value out of school as individual students do? Well the signaling model explains why. The more school is about credentialing (rather than learning), the less the nation as a whole stands to benefit from more years of it. If only a small amount of useful learning takes place, then sending every citizen to an extra year of school will result in only a small increase in the nation’s overall productivity.
Meanwhile, when you’re an individual student within a nation, getting more school can substantially increase your future earnings—not because of what you’ve learned, but because the extra school helps distinguish you as a better worker. And, crucially, it distinguishes you from other students. Thus, to the extent that education is driven by signaling rather than learning, it’s more of a competition than a cooperative activity for our mutual benefit. Sure, we’d like school to be a place where we can all get better together, but the signaling model shows us that it’s more of a competitive tournament where only so many students can “win.”
“Higher education,” says Peter Thiel, a tech billionaire famously critical of college,
sorts us all into a hierarchy. Kids at the top enjoy prestige because they’ve defeated everybody else in a competition to reach the schools that proudly exclude the most people. All the hard work at Harvard is done by the admissions officers who anoint an already-proven hypercompetitive elite. If that weren’t true—if superior instruction could explain the value of college—then why not franchise the Ivy League? Why not let more students benefit? It will never happen because the top U.S. colleges draw their mystique from zero-sum competition.18
All of this suggests that we reconsider our huge subsidies and encouragements of school. Yes, there are benefits to credentialing and sorting students—namely, the economic efficiency that results from getting higher-skilled workers into more important jobs. But the benefits seem to pale next to the enormous monetary, psychic, and social waste of the education tournament.19
BEYOND SIGNALING
Signaling certainly goes a long way toward explaining why we value education and why schools are structured the way they are. But if schools today mainly function as a credentialing apparatus, it seems like there should be cheaper, less wasteful ways to accomplish the same thing. For example, an enterprising young man could drop out of school and work an entry-level job for a few years, kind of like an apprenticeship. If he’s smart and diligent, he could conceivably get promoted to the same level he would have been hired at if he’d taken the time to finish his degree—and meanwhile, he’d be making a salary instead of studying and doing homework for free. So why don’t we see more young people doing this?
A partial (but unsatisfying) answer is that going to school is simply the norm, and therefore anyone who deviates from it shows their unwillingness to conform to societal expectations. It’s all well and good for Bill Gates or Steve Jobs to drop out of college, but most of us aren’t that talented. And what employer wants to risk hiring someone who was too antsy to complete a degree? A desire to break the mold may be attractive in a CEO, but not necessarily for someone working at a bank or paper company. By this logic, school isn’t necessarily the best way to show off one’s work potential, but it’s the equilibrium our culture happened to converge on, so we’re mostly stuck with it.
But if school is really such a waste, we might expect to see people eagerly innovating to come up with alternatives. Certainly there are some efforts in this direction, like online courses and Thiel’s sponsorship for talented students to forego college.20 But by and large, most of us accept that school is a reasonable use of our time and money, in part because school serves a wide variety of useful functions, even beyond learning skills and signaling work potential.
For young children, for example, school plays a valuable role simply as day care. Not only is it typically subsidized by the government, but the kid-to-“babysitter” ratio is quite high. Additionally, both primary and secondary schools give students an opportunity to socialize with, and be socialized by, their peers—an opportunity that homeschooled children, for example, must pursue by other means. Meanwhile, for young adults, college serves all sorts of useful functions that aren’t typically considered “educational.” College campuses are a great place to network, making friends and contacts that can be valuable later in life, both professionally and socially. It’s also a great place to meet a future husband or wife. In the United States today, roughly 28 percent of married college grads attended the same college as their spouse.21 And even when students don’t find their soulmates at college, simply going to college and graduating makes them more likely to marry someone else with a college degree, which can substantially increase their household earnings.22
These functions of college—networking and dating—can be seen as investments in a student’s future. But there’s also a sense in which going to college is an
act of consumption. In other words, some appreciate college in part because for them, it’s simply fun—like a summer camp that lasts four years. It’s a place to join clubs, go to parties, and experiment with drugs and alcohol. For a more limited set of students, even the classes themselves might be fun (shocking, we know). Looking back, most adults remember their college days with fondness. Beyond intrinsic personal enjoyment, college may also serve as conspicuous consumption—a way to signal your family’s wealth and social class (in addition to your own qualities as a worker). Many private universities seem awfully expensive relative to their rankings, and if students cared strictly about learning, they’d get a lot more bang for their buck at an inexpensive state school.
Now, none of these “hidden” functions of school are all that hidden. It doesn’t particularly bother us to admit that primary school works well as day care or that college is a great social scene. Nevertheless, these functions get short shrift in public discourse. All else being equal, we prefer to emphasize the most prosocial motive, which is that school is a place for students to learn. It costs us nothing to say that we send kids to school “to improve themselves,” which benefits society overall, and meanwhile we get to enjoy all the other benefits (including the signaling benefits) without having to appear quite so selfish and competitive.
But there are at least two other functions of school that we’re substantially less comfortable admitting to.
PROPAGANDA
Schools have been around for a long time. Our word “academic,” for example, comes from Plato’s famous Academy, named after the olive grove in which scholars met privately for lectures and discussions.23 But schools today look very little like Plato’s Academy. Specifically, our modern K–12 school system is both compulsory and largely state sponsored. How did we get here?