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Achievement Gaps
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Why Do the Achievement Gaps Exist?

  1. Explanations

    1. School Factors

Changes in Schools May Help Explain the Narrowing of the Achievement Gap in the 1970s and 1980s

Many educational changes were made in the 1970s and 1980s that may have helped black students in the U.S. Many of these changes were focused on the way that schools were organized.

This reports some of the ideas and findings from the following source:

Grissmer, D., Flanagan, A., & Williamson, S. (1998). Why did the black-white score gap narrow in the 1970s and 1980s? In C. Jencks and M. Phillips (Eds.),The black-white test score gap(pp. 182-226). Washington, DC: Brookings Institution. Pp. 206-221

To see other reports that originated from this same citation, go to the bibliography.

David Grissmer and his colleagues Ann Flanagan and Stephanie Williamson try to explain the dramatic rise in black students' test scores between 1970 and 1990. They examine test score data and information on schools to see if changes in the way schools are organized can help explain this rise in test scores. Specifically, they look at the impact of:

  • desegregation
  • increasing equity in school resources
  • smaller pupil-teacher ratios
  • higher quality teachers

Grissmer and his colleagues also look at how rising teen violence rates in the late 1980s have affected black students' test scores.

Desegregation of Black Education

Between 1968 and 1972, school segregation declined precipitously in the U.S. South. Black adolescents who began their education in the 1960s were in a very different situation from black adolescents who began their schooling in the 1970s or 1980s. Black teens who began school in the early 1960s typically received 60% of their education from schools that were at least 90% minority. This contrasts with students who began school after 1975, where 35% attended schools that were 90% or more minority.

The authors say that desegregation appears to be an important part of explaining the rise in black students' test scores. Looking at the effects of desegregation across time, desegregation is always associated with a rise in black test scores. Desegregation appears to have no consistent relationship with changes in white test scores, however.

Desegregation is not the whole story, though. While segregation dropped in the South in the 1970s, it actually rose in the U.S. Northeast. However, black students' test scores still rose in the Northeast during this period. Grissmer and his colleagues think that the rise in black students' test scores outside the South may be associated with other changes (such as antipoverty programs and the growth of affirmative action programs). So, while desegregation efforts made a difference in the South, other types of programs targeting black education made a difference in other areas of the country.

The authors think that the combination of these efforts

". . . could have led to a nationwide shift in beliefs, attitudes and motivation of black parents and students and their teachers that could help explain the subsequent nationwide improvement in black students' performance." (p. 211)

Grissmer and his colleagues also say that there is evidence that the effects of desegregation are immediate. That is, a black child does not need to have been enrolled in integrated schools from the beginning for desegregation to make a difference.

More Equity in School Resources

The authors say that until fairly recently, most social scientists did not believe that school resources had much impact on test scores. However, based on a large review of the research on the relationship between school resources and test scores, more recent scholarship has found that school spending has a positive and statistically significant effect on academic achievement, especially for certain target groups.

They say that the additional funds aimed at raising non-special-needs students' achievement went mainly for:

  • improving pupil-teacher ratio
  • creating programs for low-income students
  • paying more for teachers with more experience and more graduate training

These expenditures are associated with dramatic rises in the test scores of black students and a rise in the test scores of low-scoring white students. High-scoring white students' scores did not rise much at this time. The authors say that this result makes sense if low-scoring students, low-income students, or minority students received most of the additional resources.

Smaller Pupil-Teacher Ratios

The pupil-teacher ratio dropped between 1960 and 1990. Grissmer and his colleagues say that smaller classes appear to make a significant difference, especially for black students. In one experimental study in Tennessee, students were randomly assigned to classes of 15 or 23 students. The Tennessee study found that reducing kindergarten through third grade class sizes was associated with a significant increase in the scores of all third grade students. The effect was even greater for black than white students.

National data suggest a similar association. Smaller classes are associated with increased test scores among the most disadvantaged students (minority and poorer students). But why would smaller classes help poor and minority children more than white and advantaged children? The authors say that it is not clear why this would be the case.

The Puzzle of Higher Quality Teachers

Grissmer and colleagues look at four different teacher characteristics.

Teacher Characteristic

What Happened?

What Effect?

Level of education

The proportion of teachers with Master's degrees rose from around 25% in the 1960s to more than 50% in the 1980s.

Studies do not show consistent effects. The authors' research suggests that teacher education appears to predict student test scores about as well as class size does.

Teacher experience

The proportion of teachers with 25 years or more of experience rose from 45% in the 1960s to more than 60% for teachers entering the field in the 1970s.

Studies find that teacher experience has much weaker effects on student test scores than a teacher's level of education. However, the authors say that we need more evidence from experimental studies.

Teacher test scores

There is no evidence that teacher test scores rose between 1960 and 1990.

The authors say that teacher test scores have been linked more consistently to higher student test scores than any other characteristic.

Influx of younger teachers

The demand for new teachers more than doubled between 1960 and 1975.

The authors say that higher demand for teachers usually means that schools cannot be as choosy about who they hire. So, they may have had to settle for less-qualified teachers. They say, however, that if new teachers had more positive attitudes toward minority students, this might have had a positive effect on test scores.

In sum, Grissmer and his colleagues say that there has been little experimental research on the effects of teacher characteristics on students' test scores. They say that without experimental studies, we have little reliable evidence that teacher characteristics are associated with rising black test scores or a decrease in the black-white test score gap.

Violence Among Black Teens May Account for Test Score Setback

The authors say that while many of the changes in U.S. schools can help explain why reading test scores rose before the 1990s, they do not help explain why there was a decline in black reading test scores after 1988. Because the decline in black students' test scores occurred for all age students after 1988, the authors say that the cause seems to be something that affected all blacks, not just black students of a certain age. Also, during this period there was no corresponding decline in white students' test scores. What happened to black students that did not happen to white students?

Grissmer and colleagues say that one possible explanation is increasing violence among black teenagers. The authors point to the dramatic rise in black teen murder rates between 1985 and 1990. They say that the rise in murder rates among black teens, but not white teens, may indicate important changes in black communities.

However, the relationship between black teen violence and test scores is not as tidy as all that. Several seemingly incompatible facts still present a puzzle to researchers and educators:

  • Black teen reading scores fell during this period, while black math scores did not.
  • One study found a negative relationship between the amount of school violence a principal perceived at their school and the students' math test scores. The more perceived violence, the lower the math scores. However, this relationship was too weak to explain the entire decline in reading scores.
  • A survey found that black 10th-grade students perceived their schools as safer in 1990 than 1980.
  • It is not clear that school violence increased dramatically.

So, increasing violence in black communities (if not at school) may have had some effect on the drop in black reading scores. Grissmer and his colleagues say that math scores may not have been as affected since black students during this period were taking more demanding math courses.

Research Design:

Research Questions

Why did both black and white test scores rise for all ages in both reading and math over the past thirty years?

Why did black students' scores rise substantially more than white scores at all ages and in all subjects?

Why did black adolescent achievement scores remain stable for cohorts entering from 1960 to 1968&–1970, then suddenly accelerate for cohorts entering school between 1968&–1972 and 1976&–1980, and then stabilize or fall in subsequent cohorts?

Why did black adolescents first gain more and then lose more than black nine-year-olds?

Why did black reading gains precede black math gains?

Why were black gains higher in the Southeast and lower in the Northeast?

Why did low-scoring students gain more in math and less in reading than higher scoring students, regardless of race?


Grissmer and his colleagues draw on National Assessment of Educational Progress (NAEP) longitudinal test score data. This data source begins in the late 1960s and continues.

To determine how trends in test scores are related to other social changes, the authors relate the NAEP data to family characteristics from the Current Population Survey and the National Education Longitudinal Survey and the National Longitudinal Survey of Youth.


The authors look at the changing test scores as the dependent variable. They examine three kinds of independent variables:

  1. family characteristics
  2. changes in education
  3. changes in school organization and characteristics

They compare black and white students' test scores from the initial NAEP data to later test score trends. They measure changes from this initial starting point in terms of the standard deviation. They then regress changes in family, education, and school trends onto the changes in black and white students' test scores.


Support for Grissmore, Flanagan, and Williamson's research came from the center for Research on Educational Diversity and Excellence, supported by the U.S. Department of Education, the Danforth Foundation, and RAND.


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