But its findings are alarming and provide an argument against raising grades.
Students who experience more lenient grading are less likely to pass subsequent courses, have lower test scores afterward, are less likely to graduate from high school and enter college, and earn significantly less money a few years later.
The economic cost is not small. Denning estimates that students in that class lose about $160,000 in lifetime earnings (in current dollars) when teachers give significantly higher grades (the difference between a .2 or above on a 4-point scale, a B and almost a B+).
This is what one teacher can do in one year. If a student encounters several teachers who exaggerate their grades, the losses will add up to even greater losses.
Evidence from two very different places
The researchers examined students in two settings: Los Angeles and Maryland.
The Los Angeles Unified School District provided data on nearly 1 million high school students from 2004 to 2013, a period when graduation rates hovered above 50 percent. More than 70 percent of the students are Hispanic, and failing grades are common.
Maryland data tracked about 250,000 high school students from 2013 to 2023. The graduation rate is over 90%, and the student body is more racially mixed. The Maryland data allowed researchers to track college enrollment, employment and earnings, while the Los Angeles data ended with high school.
Despite these differences, the pattern is the same.
Students taught by lax graders (defined as teachers who give higher than expected grades based on standardized test scores and the student’s prior performance) perform worse later in high school. In Maryland, where data runs from college to the workplace, these students are also less likely to go to college or employed and earn less.
Seeing the same pattern in two very different systems is more evidence that this is not a fluke of one region or one policy system.
When does leniency help and when does it not?
This study makes an important distinction. Teachers who still keep the challenge of an A but just make it easier to pass—turning a failing grade into a low passing grade—do help more students graduate from high school, especially those at risk of dropping out. This short-term benefit is real. For some students, passing Algebra I rather than failing can put them on track to graduate and possibly attend community college.
But the benefits stop there. These students show no long-term gains in college degree completion or earnings. Leniency can help them clear the way, but it doesn’t build the skills they need afterwards.
In contrast, overall grade inflation (where teachers raise grades across the board, from C to B to A) does no good and hurts students’ chances for future success.
Why good intentions backfire
The study cannot directly explain why higher grades lead to worse outcomes. But its mechanism is not difficult to imagine. In a class with a lenient grader, a savvy student may quickly realize that she doesn’t need to study hard or complete all the assignments. If she gets a B in Algebra I but doesn’t learn how to factor or solve quadratic equations, gaps in her knowledge in geometry and other areas will follow. She might still be able to get by. Over time, the deficit worsens. Confidence erodes. Learning slows down. In college or in the workplace, the consequences manifest as lower skills and lower wages.
As Denning said in his speech, there appeared to be a “chain of cause and effect” to the harm, even though he couldn’t directly measure how much students were learning less, or falling behind.
Don’t rush to blame the teacher
Improving grades is not always decided by individual teachers. A 2025 survey documented the frustration of many teachers with inflated scores who said they felt pressure from administrators to comply with “fair grading” policies that ban zeros, allow unlimited retakes and eliminate penalties for late submissions.
Forgiving graders are not bad teachers. Studies have found that they are generally better at improving non-cognitive skills. Their students perform better, cooperate more, and are less likely to be suspended. Still, in this study, this didn’t translate into better life outcomes as one might have hoped.
Rigorous grading tends to improve student test scores in math, reading and other subjects. Despite this correlation, it doesn’t mean that all low-achieving students are good teachers. Some don’t.
This is early research. More research is needed to understand whether college grade inflation imposes similar workplace costs. There is also the question of whether boys respond differently to high scores than girls.
Teachers struggle to engage students in learning, which is fraught with frustration, frustration, and boring repetition. Maybe low grades won’t motivate students to do this hard work. But this early evidence suggests that high grades aren’t doing them any favors.
Contact a Staff Writer Jill Bacher Call 212-678-3595, jillbarshay.35 on Signal, or barshay@hechingerreport.org.
