RAND Documents Academic Gains Since 1970
American students made solid academic gains during the past two decades--despite rising numbers of one-parent families and working mothers, and other changes that critics often link to the decline of the American family, a new study has concluded.
The researchers at the RAND Corporation, a think tank based in Santa Monica, Calif., reached their conclusions by analyzing and comparing standardized-test scores and demographic statistics for teenagers in 1970 and in 1990.
The report, released late last month, says increased numbers of teenage mothers, children living in poverty, working mothers, and single-parent families over the 20-year period were offset by other more positive changes taking place among the nation's families.
The key change was that parents were better educated in 1990 than they were in 1970. But the researchers said other characteristics also helped students improve. For example, 1990 students had fewer siblings to vie for their parents' attention, they lived in households with higher incomes, and their mothers were giving birth at older ages.
"When you take into account everything that changed about families, you can say that kids in 1990 are probably living in better families for supporting achievement," David W. Grissmer, who led the study, said in an interview.
"But if you listen to the national debate, you would believe that families and schools are failing, and government programs and policies don't work."
At least since the early 1980's, a smattering of critics has contended that students' achievement nationwide has declined. Other studies suggest scores have improved in some areas. Few studies, however, have examined test scores in light of the societal changes that also took place in recent decades.
For their study, Mr. Grissmer and his colleagues--Nataraj Kirby, Mark Berends, and Stephanie Williamson--used test-score data from the National Educational Longitudinal Survey and the Longitudinal Study of American Youth, two federally supported surveys of nationally representative samples of students.
The researchers used demographic data to figure out what kinds of family characteristics influenced changes in student achievement in both surveys.
Then, they devised a formula for predicting how well students should have done on another test, the Congressionally mandated National Assessment of Educational Progress, if changes in the same demographic characteristics were taken into account. They concluded that the 9-, 13-, and 17-year-olds who take that test should have scored higher in 1990 than in 1970.
Students did in fact score higher on NAEP mathematics assessments over the 20-year span.
For white students, the improvements were about as much as the researchers expected. The scores of black and Hispanic students, however, increased about two-thirds more than they predicted.
The improvements significantly narrowed--but failed to close--the achievement gap between the minority student populations and white students.
The researchers hypothesized that the greater increases for minority students came about because the nation, beginning with the "Great Society" programs of the 1960's, put more effort into public education, social programs, and equal-opportunity policies.
Spending on public education increased over the 20-year period, for example, and much of that money was directed at low-achieving students. Head Start, a federal program aimed at disadvantaged children, and other child and nutrition programs were also launched.
"Here's some evidence that some sets of educational and social policies developed over the past 25 years look like they're responsible for raising minority test scores," Mr. Grissmer said.
The researchers warned that their findings were not conclusive.
They said their efforts make a strong case, however, for including demographic questions on future NAEP assessments and for policymakers to "go slow" before dismissing the nation's previous social-policy investments.
The study, conducted over 2-1/2 years, was sponsored by the Lilly Endowment and the U.S. Defense Department.
Copies of the report, titled "Student Achievement and the Changing American Family," are available for $15 each from RAND Distribution Services; 1700 Main St., P.O. Box 2138, Santa Monica, Calif. 90407-2138; (310) 451-7002.