Longitudinal Studies on the Benefits of Preschool

In addition to studying students for several months or a year in a day-care setting, laboratory school, or other classroom environment, researchers often seek to understand the long-term impact of early childhood education. Hence they institute longitudinal studies to track the same individuals over periods of several years or even decades. Outcomes from this type of research can inform changes to curriculum. One example of this is a study that had its roots in a startling report issued in the 1960s.

In 1969, the Westinghouse Learning Corporation and Ohio University issued a report asserting that the benefits of preschool, specifically, Head Start, were short-term, and that they “faded out” by third grade (Westinghouse, 1969). Six years later, partly in response to this report, twelve researchers formed the Consortium for Longitudinal Studies to study the effects of experimental preschool programs in the 1960s. They pooled data from multiple small individual projects and agreed to work together to track a group of 3,000 children over time (Darlington, 1981). The findings from this unique study revealed a positive, lasting impact on achievement and a lower number of children retained or placed in special education programs (Besharov, 2011; Darlington, 1981; Lazar, 1978; Lazar., 1982). This major study served to restore credibility in early education as a worthy investment.

Another important ongoing longitudinal study is the Perry Preschool Study (PPS), which began in 1962. It was designed to evaluate the long-term effectiveness of High Scope, a specific curriculum that emphasizes active learning and family involvement and was used as an early intervention measure.

In Ypsilanti, Michigan, 123 poor African American children between the ages of 3 and 4 were divided into two groups, with one group attending preschool at the Perry Elementary School. There, the High Scope curriculum was implemented from 1962 to 1967. The other group also attended preschool but did not use the High Scope curriculum. Researchers have checked in with the children, who are now in their forties, ever since, and have updated their findings periodically (Schweinhart, 2005). The study continues to find that those in the High Scope preschool program had more positive long-term outcomesin terms of earnings, level of education and employment rates, and crime statisticsthan those who attended the other preschool (Figure 2.2). “The High Scope Perry Preschool Study is now widely regarded as a landmark study that established the human and financial value of high-quality preschool education” (Schweinhart, 2002).

The Abecedarian Project, from the University of North Carolina, shifted the focus of study from federally funded preschool classrooms to low-income children in a child care setting. Educational activities were developed in the form of “games” intended for all domains of development, with particular emphasis on language. Findings were reported on the children at ages 12 (Campbell, 1994), 15 (Campbell., 1995), and 21 (Campbell, Ramey, Pungello, Sparling, & Miller-Johnson, 2002); these linked the importance of high-quality child care begun at infancy to later academic success and achievement. Because each child received individualized attention from a teacher, this study also provided evidence of the importance of well-educated teachers (Campbell, 1994, 1995; Campbell et al., 2002; University of North Carolina, 1999; Masse, 2002).