PRES. BARACK OBAMA'S proposal of "high-quality preschool for all," with $75,000,000,000 in Federal start-up money, inspired similar calls for universal preschool by state and local leaders throughout the country. New York Mayor Bill de Blasio ran on a universal pre-K platform, funded by "taxing the rich," while New York Gov. Andrew Cuomo also has endorsed universal pre-K funded from existing tax monies. Preschool was a major issue in the gubernatorial races in Texas and Ohio, with both Democratic candidates endorsing universal pre-K. Moreover, the California legislature has proposed expanding its coverage of "transitional kindergarten" to all four-year-olds, thereby becoming a universal pre-K program.
Expanding public schooling to cover all four-year-olds would require a significant increase in state and Federal spending. Even if Congress authorized the full Obama proposal, which covers a 10-year period, total expenditures for the states would be far higher. With U.S. expenditures for public schooling from all sources exceeding $12,000 per student, and with approximately 4,000,000 students enrolled in public kindergartens, states could be spending nearly $50,000,000 per year to fund universal preschool, assuming that spending levels for preschool are similar to those for higher grades.
With such large proposed expenditures, the benefits of pre-K should be clear and definitive. Yet, existing research on preschool programs does not paint a uniformly positive picture, despite what supporters claim. Indeed, the most rigorous studies of contemporary preschool programs, particularly the Federal Head Start program and a Tennessee universal program, show no lasting gains for preschool students after they enter regular grades. According to these studies, by the time children reach the early elementary grades, the average preschool student has learned no more than children who were not in preschool.
How are these results reconciled with proclamations, including some from the White House, about the dramatic benefits of preschool? Are universal preschool advocates simply ignoring scientific evidence? There is a body of research that finds educational benefits from preschool programs, but these studies suffer from one of two problems: either the preschool programs are not comparable with the programs being proposed today, or they use nonexperimental designs that suffer from serious limitations, including an inability to track preschool effects into the early grades.
Supporters of preschool programs have been very selective in their research citations. They extol programs with large pre-K effects as "high quality," especially some historical programs, as well as several recent pre-K programs in Tulsa, Okla., and Boston, Mass. Meanwhile, they ignore the Head Start findings or imply that it is not a high-quality program.
There are three historical "high-quality" preschool programs that have received considerable attention. These are the Abecedarian project in North Carolina, the Perry Preschool program in Michigan, and the Chicago Child-Parent preschool program. These historical programs differ markedly from contemporary preschools in ways that make them uncomparable to current and proposed "high-quality" preschool programs. In addition, one of them has some serious methodological limitations.
The Abecedarian program and study was conducted at the University of North Carolina, Chapel Hill, during the early 1970s. It was a relatively well-designed randomized experiment involving 111 low-income infants, nearly all black, 57 of whom were in the treatment group. The program involved interventions from infancy (average of four months) to the start of kindergarten.
A Child Development Center provided intensive care and education for up to 40 hours a week for 50 weeks. Follow-up studies, both short- and long-term, found significant gains for the treatment group as compared to the control group on various cognitive and IQ tests up to age 21. However, this very intensive and much longer intervention is not comparable to any contemporary statewide or city preschool program, most of which are designed for a single year of pre-K. It also is worth noting that randomization was done prior to asking mothers' permission to participate, and a higher refusal rate by control group mothers might have produced some bias in results.
The Perry Preschool program and research took place in Ypsilanti, Mich., in the mid 1960s, and involved 123 predominantly black children who attended the Perry Elementary School. It also was a randomized experiment, with 59 students assigned to the preschool program, although the research design was compromised somewhat by switching two working mothers to the control group and by some program dropouts. Many years later, this program was the subject of a rigorous cost-benefit study conducted by a group of economists led by James Heckman, who undertook major analyses to compensate for the design flaws. They found that the costs of the Perry Preschool program--which would be about $20,000 per child in current dollars--were more than paid back by higher employment rates, lower rates of crime, and other economic outcomes favoring the preschool group. The Heckman findings generated a great deal of publicity, and they were cited extensively by the White House in support of the Obama proposal.
While the Perry Preschool program is more like a contemporary preschool than the Abecedarian project, the Perry program consisted of two years of preschool coupled with weekly visits with the parent. Because of the home visits, child-teacher ratios were very small, just five or six children per teacher, far lower than contemporary pre-K programs. Given the critical role parents play in child development, home visits were an important feature of Perry Preschool. The very low child-teacher ratios and the home visits make the Perry Preschool experience uncomparable to the type of preschool programs endorsed by Pres. Obama and other political leaders. Therefore, the cost-benefit results for the Perry program cannot be extrapolated to most contemporary preschool programs, even those that are described as "high quality."
The Chicago Child Parent Center program, which started in 1967, also differs in several ways from standard preschool programs. Like Perry Preschool, there is mandatory parent involvement during the program. Unlike Perry and other preschool initiatives, it also has follow-on components that continue into the higher grades. Also unlike Perry, it never has been evaluated by a randomized experimental design. Instead, control group children have been selected from other low-income schools, and statistical adjustments have been used to create equivalence. However, self-selection bias is hard to eliminate in studies of this type, particularly when a program runs over multiple years. There is a very high likelihood that treatment outcomes are biased upward by attrition or dropouts who do not complete all years of the program.
Among contemporary evaluations of regular pre-K programs initiated since the year 2000, two stand out because both used randomized experimental designs. These...