Research into the practice of paying students to perform at school is showing mixed results, and it’s highlighting problems with an approach that relies on rewards after more than a decade in practice.

Education Week recently highlighted efforts by some schools to incentivize student attendance or performance through a variety of means, from cash to cars. The practice first gained traction following the federal No Child Left Behind Act passed by Congress in 2001, and the resulting research in both the U.S. and internationally shows results depend a lot on how programs are designed.

One of the biggest studies involved Harvard University economist Roland Fryer, who led a series of experiments through the mid-2000s that paid out over $6 million to more than 18,000 low-income students in Chicago, Dallas, New York City, and the District of Columbia in hopes of improving test scores.

According to Ed Week:

The major takeaway from Fryer’s research is that inducements are more likely to work if a program incentivizes things students feel they can control. In technical terms, that means rewarding inputs instead of outputs, said Jeffrey Livingston, an associate professor of economics at Bentley University. Students don’t necessarily know how to improve their test scores, so even if they’re motivated to try harder, that doesn’t mean they can actually do better.

“If the incentive is tied to the performance on the test, the effects are small if there at all,” said Livingston. “But if you tie it to the preparation for the test, the studying, like incentivizing reading a book or doing practice tests . . . that tends to have much bigger effects.”

In other places, similar efforts also met mixed results, though some school officials contend it’s had a generally positive effect.

The Union R-XI School District in Missouri offered students up to $100 for perfect attendance at summer school, Tennessee’s Shelby County schools offered Memphis Grizzlies tickets to students with good attendance, and the famed Success Academy charter school network has also offered small prizes like Nerf guns for good behavior.

“I think rallying around something that’s such a positive, fun way to improve attendance helps change the culture of the school,” Megan Berceau, intervention specialist at the Granite school district in Utah, told Ed Week.

Berceau said incentives like allowing students to ride non-motorized scooters to class as a reward for good attendance has kept some of them motivated.

Others, including Raytown, MO, Superintendent Allan Markley said incentives that offer something students truly want is the key. In Raytown, school officials raffled off two cars to students with top attendance.

“A lot of kids are working to support their family, a lot of them are homeless. What can we do to entice kids to come to school? They are dealing with a lot and coming to school may not be their number one priority,” Markley said. “So, what does every 16-year-old dream of? Something with four wheels, maybe?”

Incentives haven’t worked as well in many other districts, however.

Parents complained in 2015 when a New Jersey school district announced plans to award gift cards to students who showed up to take state standardized tests, for example.

Tulane University education researcher Douglas Harris contends many parents and educators oppose the incentives because they seemingly contradict the purpose of education.

“If your goal is to instill a love of learning, paying students to read books doesn’t really do that,” he told Ed Week. “It doesn’t reflect the view of teaching and learning that most educators support. They don’t want it to be transactional.”

Incentivizing youngsters to encourage good behavior using bribes, consequences, or surveillance is nothing new, and the programs in place at many schools simply formalize a process that’s been used by parents for years.

But there’s a difference between bribing students into good behavior and motivating them to do what’s right for its own sake. Parents and educators successfully instill responsible behavior when students do what’s right without incentives. The ultimate goal is to cultivate a moral autonomy that allows them to make those decisions on their own.

James Davison Hunter wrote in The Tragedy of Moral Education in America that “ . . . character education programs can work . . . when people react to the idea of acting in certain ways the way most Americans react to the idea of eating grubs.

“The right and wrong things to do should be as instinctive and as obvious as we feel food taboos to be, when the first answer to why we will do this is just ‘Well, because.’”

To develop “good sense” in students about doing right and wrong, the Jubilee Centre for Character and Virtues offers a lesson framework for teachers, administrators, and parents.