A new study says that assigning black students from low-income black families to at least one black teacher in the third, fourth or fifth grades reduces the probability that they drop out of high school by 29 percent. The results are even larger for male African American students from persistently low-income families: Their chance of dropping out of high school falls 39 percent.

The study also found that black students of both genders from low-income families are more likely to aspire to attend a four-year college if they have at least one black teacher between third and fifth grades There was, however, no effect found on the dropout decisions of female students, “perhaps due to females’ significantly higher baseline graduation rates,” the study said.

The results are the latest in a growing body of evidence that race affects how teachers view and treat their students. As my colleague Emma Brown wrote in this story, black students taught by white teachers are less likely to be identified for gifted programs than black students taught by black teachers, and biases exist in teachers’ grading of work by students of different genders, races and ethnicities.

The new study was published by the IZA Institute of Labor Economics, an independent economic research institute in Germany, and conducted by Seth Gershenson, an associate professor in the Department of Public Administration and Policy at American University and IZA; Cassandra M.D. Hart, an assistant professor of education policy at the University of California at Davis; Constance A. Lindsay, a professorial lecturer in the School of Public Affairs of American University; and Nicholas W. Papageorge, assistant professor of economics at Johns Hopkins University and IZA.

The study goes beyond previous research that showed short-term benefits to pairing students with teachers of the same race, demonstrating longer-term affects. The implications are important, Papageorge said, because policymakers can act quickly to improve black students’ chances of academic success.

“This isn’t a situation where students need two, three or four black teachers to make a difference,” he was quoted as saying in a Johns Hopkins release. “This could be implementable tomorrow. You could literally go into a school right now and switch around the rosters so that every black child gets to face a black teacher.”

Actually, it may not be that easy. A report released by the Education Department in 2016 said that the latest data found that about 82 percent of teachers in America’s public schools are white; 8 percent are Hispanic; 7 percent are black, with only 2 percent black males; 2 percent are Asian; and about half of a percent are American Indian or Alaska Native. Sixty-three percent of teachers working in high-poverty elementary and secondary schools were white; 16 percent were black and 16 percent were Hispanic, the data said. And teachers of color are overwhelmingly employed in public schools serving student populations with relatively high proportions of students of color and public schools in urban areas.

For the study, the researchers first looked at longitudinal data on about 100,000 black students who entered third grade in North Carolina public schools between 2001 and 2005. Then they studied black students in Tennessee who entered kindergarten in the late 1980s and participated in a class-size reduction experiment; they found that students who had at least one black teacher in kindergarten through grade three were 15 percent less likely to drop out and 10 percent more likely to take a college-entrance exam.

Why? The researchers found no definitive answer, but they noted in the study that one explanation could be the “role model effect.” In this line of thinking, the study says, “black teachers have higher educational expectations for black students, which in turn increase black students’ educational engagement and aspirations.”

A 2016 study co-authored by Papageorge found that white and black teachers do have different expectations for black students, raising questions about whether biases held by teachers is a factor in the achievement gap between black and white students. According to that study, a white or other nonblack teacher is 30 percent less likely to believe that a student will graduate from a four-year college than a black teacher who is evaluating the same black student. The nonblack teacher is 40 percent less likely to believe the student will graduate from high school than the black teacher — and the results for black male students was worse.

There are critics of the idea that simply assigning black students to black teachers can make an important difference in academic outcomes. Christopher Emdin, an associate professor at Teachers College, Columbia University, wrote this in the New York Times in 2016:

How can we help black boys succeed in school? One popular answer is that we need more black male teachers.
The logic appears simple: Black boys are not faring well, and the presence of black men as teachers and role models will fix this problem … The argument may be well intentioned, but it is a cop-out. Schools are failing black male students, and it’s not because of the race of their teachers. These students are often struggling with the adverse effects of poverty, the inequitable distribution of resources across communities and the criminalization of black men inside and outside of schools. Black male teachers can serve as powerful role models, but they cannot fix the problems minority students face simply by being black and male.