“A journey of a thousand miles begins with a single step.”
So said Lau Tzi (or Lau Tzu), the great Chinese scholar who lived in the 6th century BC.
For many years, especially since the extraordinary long-term outcomes of the Perry Preschool became known, many educators have seen high-quality preschool as an essential “first step” in a quality education. Truly, a first step in a journey of a thousand miles. Further, due to the Perry Preschool findings, educators, researchers, and policy makers have maintained that quality preschool is not only the first step in a quality education, but it is the most important, capable of making substantial differences in the lives of disadvantaged students.
I believe, based on the evidence, that high-quality preschool helps students enter kindergarten and, perhaps, first grade, with important advantages in academic and social skills. It is clear that quality preschool can provide a good start, and for this reason, I’d support investments in providing the best preschool experiences we can afford.
But the claims of most preschool advocates go far beyond benefits through kindergarten. We have been led to expect benefits that last throughout children’s lives.
Would that this were so, but it is not. The problem is that randomized studies rarely find long-term impacts. In such studies, children are randomly assigned to receive specific, high-quality preschool services or to serve in a control group, in which children may remain at home or may receive various daycare or preschool experiences of varying quality. In randomized long-term studies comparing students randomly assigned to preschool or business as usual, the usual pattern of findings shows positive effects on many measures at the end of the preschool year, fading effects at the end of kindergarten, and no differences in later years. One outstanding example is the Tennessee Voluntary Prekindergarten Program (Lipsey, Farran, & Durkin, 2018). A national study of Head Start by Puma, Bell, Cook, & Heid (2010) found the same pattern, as did randomized studies in England (Melhuish et al., 2010) and Australia (Claessens & Garrett, 2014). Reviews of research routinely identify this consistent pattern (Chambers, Cheung, & Slavin, 2017; Camilli et al., 2009; Melhuish et al., 2010).
So why do so many researchers and educators believe that there are long-term positive effects of preschool? There are two answers. One is the Perry Preschool, and the other is the use of matched rather than randomized study designs.
The Perry Preschool study (Schweinhart & Weikart, 1997) did use a randomized design, but it had many features that made it an interesting pilot rather than a conclusive demonstration of powerful and scalable impacts. First, the Perry Preschool study had a very small sample (initially, 123 students in a single school in Ypsilanti, Michigan). It allowed deviations from random assignment, such as assigning children whose mothers worked to the control group. It provided an extraordinary level of services, never intended to be broadly replicable. Further, the long-term effects were never seen on elementary achievement, but only appeared when students were in secondary school. It seems unlikely that powerful impacts could be seen after there were no detectable impacts in all of elementary school. No one can fully explain what happened, but it is important to note that no one has replicated anything like what the Perry Preschool did, in all the years since the program was implemented in 1962-1967.
With respect to matched study designs, which do sometimes find positive longitudinal effects, a likely explanation is that with preschool children, matching fails to adequately control for initial differences. Families that enroll their four-year-olds in preschool tend, on average, to be more positively oriented toward learning and more eager to promote their children’s academic success. Well-implemented matched designs in the elementary and secondary grades invariably control for prior achievement, and this usually does a good job of equalizing matched samples. With four-year-olds, however, early achievement or IQ tests are not very reliable or well-correlated with outcomes, so it is impossible to know how much matching has equalized the groups on key variables.
Preparing for a Journey
Lao Tzi’s observation reminds us that any great accomplishment is composed of many small, simple activities. Representing a student’s educational career as a journey, this fits. One grand intervention at one point in that journey may be necessary, but it is not sufficient to ensure the success of the journey. In the journey of education, it is surely important to begin with a positive experience, one that provides children with a positive orientation toward school, skills needed to get along with teachers and classmates, knowledge about how the world works, a love for books, stories, and drama, early mathematical ideas, and much more. This is the importance of preschool. Yet it is not enough. Major make-or-break objectives lie in the future. In the years after preschool, students must learn to read proficiently, they must learn basic concepts of mathematics, and they must continue to build social-emotional skills for the formal classroom setting. In the upper elementary grades, they must learn to use their reading and math skills to learn to write effectively, and to learn science and social studies. Then they must make a successful transition to master the challenges of secondary school, leading to successful graduation and entry into valued careers or post-secondary education. Each of these accomplishments, along with many others, requires the best teaching possible, and each is as important and as difficult to achieve for every child as is success in preschool.
A journey of a thousand miles may begin with a single step, but what matters is how the traveler negotiates all the challenges between the first step and the last one. This is true of education. We need to find effective and replicable methods to maximize the possibility that every student will succeed at every stage of the learning process. This can be done, and every year our profession finds more and better ways to improve outcomes at every grade level, in every subject. Preschool is only the first of a series of opportunities to enable all children to reach challenging goals. An important step, to be sure, but not the whole journey.
Photo courtesy of Allison Shelley/The Verbatim Agency for American Education: Images of Teachers and Students in Action.
Camilli, G., Vargas, S., Ryan, S., & Barnett, S. (2009). Meta-analysis of the effects of early education interventions on cognitive and social development. Teachers College Record, 112 (3), 579-620.
Chambers, B., Cheung, A., & Slavin, R.E. (2016) Literacy and language outcomes of comprehensive and developmental-constructivist approaches to early childhood education: A systematic review. Educational Research Review, 18, 88-111..
Claessens, A., & Garrett, R. (2014). The role of early childhood settings for 4-5 year old children in early academic skills and later achievement in Australia. Early Childhood Research Quarterly, 29, (4), 550-561.
Lipsey, M., Farran, D., & Durkin, K. (2018). Effects of the Tennessee Prekindergarten Program on children’s achievement and behavior through third grade. Early Childhood Research Quarterly, 45 (4), 155-176.
Melhuish, E., Belsky, J., & Leyland, R. (2010). The impact of Sure Start local programmes on five year olds and their families. London: Department for Education.
Puma, M., Bell, S., Cook, R., & Heid, C. (2010). Head Start impact study: Final report. Washington, DC: U.S. Department of Health and Human Services.
Schweinhart, L. J., & Weikart, D. P. (1997). Lasting differences: The High/Scope Preschool curriculum comparison study through age 23 (Monographs of the High/Scope Educational Research Foundation No. 12) Ypsilanti, MI: High/Scope Press.
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This blog was developed with support from the Laura and John Arnold Foundation. The views expressed here do not necessarily reflect those of the Foundation.