New research into what is commonly called the black-white “achievement gap” suggests that the students who lose the most ground academically in U.S. public schools may be the brightest African-American children.
As black students move through elementary and middle school, these studies show, the test-score gaps that separate them from their better-performing white counterparts grow fastest among the most able students and the most slowly for those who start out with below-average academic skills.
“We care about achievement gaps because of their implications for labor-market and socioeconomic-status issues down the line,” said Lindsay C. Page, a Harvard University researcher, commenting on the studies. “It’s disconcerting if the gap is growing particularly high among high-achieving black and white students.”
Disconcerting, but not surprising, said researchers who have studied achievement gaps. Studies have long shown, for instance, that African-American students are underrepresented among the top scorers on standardized tests, such as the National Assessment of Educational Progress. Fewer studies, though, have traced the growth of those gaps among high and low achievers.
The reasons why achievement gaps are wider at the upper end of the achievement scale are still unclear. But some experts believe the patterns have something to do with the fact that African-American children tend to be taught in predominantly black schools, where test scores are lower on average, teachers are less experienced, and high-achieving peers are harder to find.
The two new working papers, which were presented at last month’s annual meeting of the American Educational Research Association in New York City, use different test data and research designs to tackle that question. Yet both arrive at similar conclusions.
For his analysis, Sean F. Reardon, an associate professor of sociology and education at Stanford University, analyzed reading and mathematics scores for nearly 7,000 elementary students taking part in a federal study known as the Early Childhood Longitudinal Study-Kindergarten Cohort. From kindergarten to 5th grade, he found, the achievement gaps grew twice as fast among the students who started out performing above the mean than they did among lower-performing children.
“The long-term implication of this is that, if these gaps continue to grow throughout their schooling career, even kids who enter kindergarten with high levels of readiness are going to end up falling below where they started,” said Mr. Reardon.
In the second study, economists Steven G. Rivkin and Eric A. Hanushek tracked 800,000 Texas children as they moved from 3rd through 8th grades in successive waves.
The researchers grouped the students into four quartiles, based on their 3rd grade scores in reading, and studied each group’s progress on state math tests taken in 3rd and 5th grades. The higher the initial achievement score, the researchers found, the more scores diverged over time between black and white students. (In contrast to Mr. Reardon’s study, however, the gap among high achievers at 8th grade was still slightly smaller than the gap at the low end of the achievement scale, even though the rate of growth in the black-white gap was greater at the upper end.)
One possible reason for the faster rate of growth in the gap among higher achievers is that African-American students, by and large, attend schools where a large proportion of the students are black, according to Mr. Rivkin, an economics professor at Amherst College in Massachusetts, and Mr. Hanushek, who is a senior fellow at the Hoover Institution.
“It appears on average to be worse for a child to be in a school with a high black enrollment share, but it’s not clear why,” said Mr. Rivkin. “It could be important given the recent [U.S.] Supreme Court decision on desegregation,” he added, referring to a ruling in June of last year that sharply limited schools from using race to assign students to schools.
Mr. Reardon reasoned that, because schools with predominantly African-American enrollments tend to have lower average test scores, high-achieving black children may be further from the mean, academically, than is the case for top-scoring white children.
“If instruction is aimed more to the middle of the distribution, then black children are less likely to have cognitively stimulating opportunities—not because anyone is being racist, but because the thing to do is aim instruction to the average level of the school,” he said.
In the Texas study, the researchers also found that black children on average were taught by less experienced teachers. But that seemed to more adversely affect the low-achieving African-American students in the sample than the high performers, according to that analysis.
Some other research also suggests that high-achieving black children in some schools face more peer pressure to mask their academic abilities and that black children, on average, tend to have fewer opportunities for intellectual enrichment outside of school, which might be particularly important for bright students.
“We need to pay more attention to micro-level dynamics,” said John B. Diamond, an associate professor of education at Harvard who is not connected with the two new studies. “There may be some issues around teacher expectations tied into race that have something to do with these outcomes. You really have to parse out educational opportunities and see what differences might be there.”
A third paperat the same AERA session found that differences between the schools that black and white students attend began playing an increasingly important role in recent decades in the growth of racial achievement gaps at the national level.
That analysis, which was conducted by Ms. Page, a doctoral student, and two Harvard professors, also determined that the national gap, which narrowed in the 1970s and 1980s and then widened again in the 1990s, tracked closely to changes in the percentages of white and black parents with more than a high school education.
At least one other recent longitudinal study examined growth in racial achievement gaps at the student level over time, according to Mr. Reardon.
Tracking North Carolina students in grades 3-8, that study found the black-white gap in math widened for students who started out achieving at the 90th percentile or higher and narrowed among students at the bottom of the distribution. Those researchers attributed the trend, however, to new state policies that put pressure on schools to reduce the numbers of students scoring at minimum levels on state tests.
“It’s not a well-known finding or one that people talk about, even if people have found it before,” said Ronald G. Ferguson, the director of Harvard’s Achievement Gap Initiative, said about the gap’s differential impact on high-scoring students. “But it’s not surprising.”
Coverage of education research is supported in part by a grant from the Spencer Foundation.
A version of this article appeared in the April 16, 2008 edition of Education Week as Black-White Gap Widens Faster for High Achievers