How Children Succeed book excerpt: What the most boring test in the world tells us about motivation and IQ.
Is Motivation More Important Than Cognitive Ability When It Comes to Children's Success?
The state of the universe.
Sept. 5 2012 10:43 AM

How Children Succeed

Which matters more, cognitive ability or motivation?

Some M&M's for your thoughts?
Some M&M's for your thoughts?

Photograph by Anders Lagerås/Wikimedia Commons.

The following article is adapted from Paul Tough's How Children Succeed: Grit, Curiosity, and the Hidden Power of Character, out now from Houghton Mifflin Harcourt.

Angela Duckworth, a psychologist at the University of Pennsylvania, has made it her life’s work to analyze which children succeed and why. She says she finds it useful to divide the mechanics of achievement into two separate dimensions: motivation and volition. Each one, she says, is necessary to achieve long-term goals, but neither is sufficient alone. Most of us are familiar with the experience of possessing motivation but lacking volition: You can be extremely motivated to lose weight, for example, but unless you have the volition—the willpower, the self-control—to put down the cherry Danish and pick up the free weights, you’re not going to succeed. If children are highly motivated, self-control techniques and exercises—things like learning how to distract themselves from temptations or to think about their goals abstractly—might be very helpful. But what if students just aren’t motivated to achieve the goals their teachers or parents want them to achieve? Then, Duckworth acknowledges, all the self-control tricks in the world aren’t going to help.

But that doesn’t mean it’s impossible to shift a person’s motivation. In the short term, in fact, it can be surprisingly easy. Consider a couple of experiments done decades ago involving IQ and M&M’s. In the first test, conducted in Northern California in the late 1960s, a researcher named Calvin Edlund selected 79 children between the ages of 5 and 7, all from “low-middle class and lower-class homes.” The children were randomly divided into an experimental group and a control group. First, they all took a standard version of the Stanford-Binet IQ test. Seven weeks later, they took a similar test, but this time the kids in the experimental group were given one M&M for each correct answer. On the first test, the two groups were evenly matched on IQ. On the second test, the IQ of the M&M group went up an average of 12 points—a huge leap.


A few years later, two researchers from the University of South Florida elaborated on Edlund’s experiment. This time, after the first, candy-less IQ test, they divided the children into three groups according to their scores on the first test. The high-IQ group had an average IQ score on the first test of about 119. The medium-IQ group averaged about 101, and the low-IQ group averaged about 79. On the second test, the researchers offered half the children in each IQ category an M&M for each right answer, just as Edlund had; the others in each group received no reward. The medium-IQ and high-IQ kids who got candy didn’t improve their scores at all on the second test. But the low-IQ children who were given M&M’s for each correct answer raised their IQ scores to about 97, almost erasing the gap with the medium-IQ group.

The M&M studies were a major blow to the conventional wisdom about intelligence, which held that IQ tests measured something real and permanent—something that couldn’t be changed drastically with a few candy-covered chocolates. They also raised an important and puzzling question about the supposedly low-IQ children: Did they actually have low IQs or not? Which number was the true measure of their intelligence: 79 or 97?

This is the kind of frustrating but tantalizing puzzle that teachers face on a regular basis, especially teachers in high-poverty schools. You’re convinced that your students are smarter than they appear, and you know that if they would only apply themselves, they would do much better. But how do you get them to apply themselves? Should you just give them M&M’s for every correct answer for the rest of their lives? That doesn’t seem like a very practical solution. And the reality is that for low-income middle-school students, there are already tremendous rewards for doing well on tests—not immediately and for each individual correct answer, but in the long term. If a student’s test scores and GPA through middle and high school reflect an applied IQ of 97 instead of 79, he is much more likely to graduate from high school and then college and then to get a good job—at which point he can buy as many bags of M&M’s as he wants.

But as every middle-school teacher knows, convincing students of that logic is a lot harder than it seems. Motivation, it turns out, is quite complex, and rewards sometimes backfire. In their book Freakonomics, Steven Levitt and Stephen Dubner recount the story of a study researchers undertook in the 1970s to see if giving blood donors a small financial stipend might increase blood donations. The result was actually that fewer people gave blood, not more.

And while the M&M test suggests that giving kids material incentives to succeed should make a big difference, in practice, it often doesn’t work that way. In recent years, the Harvard economist Roland Fryer has essentially tried to extend the M&M experiment to the scale of a metropolitan school system. He tested several different incentive programs in public schools—offering bonuses to teachers if they improved their classes’ test results; offering incentives like cellphone minutes to students if they improved their own test results; offering families financial incentives if their children did better. The experiments were painstaking and carefully run—and the results have been almost uniformly disappointing. There are a couple of bright spots in the data—in Dallas, a program that paid young kids for each book they read seems to have contributed to better reading scores for English-speaking students. But for the most part, the programs were a bust. The biggest experiment, which offered incentives to teachers in New York City, cost $75 million and took three years to conduct. And in the spring of 2011, Fryer reported that it had produced no positive results at all.

This is the problem with trying to motivate people: No one really knows how to do it well. It is precisely why we have such a booming industry in inspirational posters and self-help books and motivational speakers: What motivates us is often hard to explain and hard to measure.

Part of the complexity is that different personality types respond to different motivations. We know this because of a series of experiments undertaken in 2006 by Carmit Segal, then a postdoctoral student in the Harvard economics department and now a professor at a university in Zurich. Segal wanted to test how personality and incentives interacted, and she chose as her vehicle one of the easiest tests imaginable, an evaluation of basic clerical skills called the coding-speed test. It is a very straightforward test. First, participants are given an answer key in which a variety of simple words are each assigned a four-digit identifying number. The list looks something like this: 


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