January/February 2006

Research Points to the Long-Term Benefits of Preschool

For more than four decades, researchers of early childhood education have been finding that quality preschool programs have an impact not just on kindergarten readiness, but on participants’ learning and success in later life. “The studies are very clear,” says W. Steven Barnett, director of the National Institute for Early Education Research (NIEER), an early childhood education research organization based at Rutgers University. “Good preschool programs have a very large and long-term positive impact.”

In 1962, David Weikart and colleagues in the Ypsilanti, Michigan, school district launched the landmark Perry Preschool Project, identifying 123 low-income African American children who were thought to be at high risk of school failure. The researchers randomly assigned 58 children to a part-day, high quality early care and education setting; the rest received no preschool services. (The definition of high quality preschool includes factors such as highly trained teachers with appropriate credentials; teacher salaries comparable to those of teachers in the elementary grades; small group sizes and student-teacher ratios; and an emphasis on the “whole child.”) Researchers collected data annually on both groups from ages 3 through 11, and again at ages 14, 15, 19, 27, and 40.

The most recent Perry Preschool report, released when participants turned 40, points to the program’s effects at various points in the participants’ lives. At age 5, 67 percent of the children who had attended preschool scored 90 or higher on IQ tests, compared to just 27 percent of those in the control group. Sixty-five percent of the preschool group also graduated from high school, compared to just 45 percent of those who received no services. By age 40, those who had participated in the preschool program had significantly fewer arrests and significantly better chances of earning higher salaries. Notes Barnett, a coauthor of several monographs reporting the participants’ progress, “This is not just one of the best preschool studies around, but one of the best longitudinal data sets on low-income African Americans.”

Ten years after the Perry Preschool study started, researchers at the University of North Carolina at Chapel Hill began the Carolina Abecedarian Project, a study of 111 socioeconomically disadvantaged children, this time beginning at infancy. Fifty-seven infants between six weeks and six months of age were chosen to attend a full-day, year-round early childhood development and education program. (The remaining 54 infants received no services.) Teachers in the program used a variety of activities to focus on social, emotional, and cognitive areas of development, giving particular emphasis to language.

Five years later, when the children entered kindergarten, researchers divided the whole group of participants in half again. One half participated in the regular kindergarten program with no additional services; the other half received the services of a special resource teacher in addition to the regular kindergarten program. The teacher prepared an individualized set of home activities and provided tutoring, home services, and family support.

In the end, the researchers had four subgroups to compare: children who received preschool services and special resource services in kindergarten; children who received preschool services but no special resource services in kindergarten; children who did not receive preschool services but did have the special resource teacher in kindergarten; and children who received no services at all.

The researchers found that the children who had spent the most time in the Abecedarian program were the least likely to fail a grade and did the best on reading, math, and intelligence tests. What’s more, the children who received the preschool intervention (even if it was the only intervention in which they participated) did better on all counts than those who received services just in primary school. A follow-up study of the Abecedarian kids at age 21 found that those who participated were not only more likely to perform well on intelligence tests, but also to pursue higher education, to abstain from using marijuana and tobacco, and to postpone having children.

At about the same time, researchers led by Arthur J. Reynolds, a professor of social work at the University of Wisconsin-Madison, were in the midst the Chicago Longitudinal Study, involving approximately 1,500 children from low-income, largely African American families in Chicago. Nearly 1,000 of the children participated in the Chicago School District’s Child-Parent Center Program (CPC) beginning at age three, while the rest attended other early childhood intervention programs or went straight into kindergarten. The 15-year study, released in 2001, measured the children’s progress on key educational and social milestones.

Among the findings:

• Juvenile arrest rates were 16.9 percent for the CPC preschool group, compared to 25.1 percent for the comparison group.
• The CPC preschool group, by age 20, had a high school completion rate 29 percent higher than the other participants.
• The rate of grade retention was significantly lower for the preschool group (23 percent) than for the comparison group (28.4 percent).

Taken collectively, Reynolds concluded, the findings had major economic implications. In a related study, he and other researchers found that for every dollar invested in the preschool program, the return to society at large was $7.14 in money that would have otherwise been spent on remedial education and justice-system expenditures and in increased earnings and tax revenues.

“These are really life-altering outcomes for young people, with major implications for society,” Reynolds says.

Sue Miller Wiltz is a journalist in Indianapolis and has been a correspondent for Newsweek, People, and Court TV.