Some of the most well-known evaluations of preschool—studies such as Perry Preschool, which tracked a group of Ypsilanti, Mich., children for decades and found long-lasting positive benefits—are measuring effects of programs that would be difficult to replicate on a large scale today.
Perry Preschool, for example, involved an intensive curriculum taught by teachers with bachelor’s degrees, weekly home visits by teachers to childrens’ homes, and cost nearly $18,000 per child. That’s several times the average cost per child of today’s public preschool programs.
[UPDATE: (March 21): Rob Grunewald, an economist at the Federal Reserve Bank of Minneapolis who writes frequently about early-childhood education (including for Education Week) suggested a useful clarification for the Perry Preschool cost. The nearly $18,000 cost per child is accurate, but most children in the program participated for not quite two years. The cost per child, per year in the Perry Preschool program is closer to about $11,000 in today’s dollars, Grunewald says.]
But current city- and state-run preschool programs, for all their differences from the boutique programs of the past, still show positive effects for children who enroll in them, according to a new analysis from the RAND Corporation. However, quality programming is key to seeing benefits, said Lynn A. Karoly, a senior economist at RAND and the study’s lead author.
The RAND analysis looked at studies of preschool programs in Boston, Chicago, and Tulsa, Okla. It also examined studies in Georgia, Michigan, New Mexico, Tennessee, and West Virginia, among other states. The analysis also incorporated the 2012 results of an extensive study Head Start’s effects.
The Head Start Impact Study and the study of Tennessee’s prekindergarten program have been held up as examples of program “fade-out.” Both of those studies tracked children who were randomly assigned to the program and compared them to children who were not assigned to the program. In both cases, the academic skills of the children who attended the program matched their peers who had not enrolled by the time the children were in 3rd grade.
Exploring Reasons for Preschool ‘Fade-Out’
Those findings illustrate why program quality is so important, Karoly said. Both Head Start and Tennessee’s preschools aren’t programs as much as funding streams, she said, and the quality of individual providers can vary a lot. In contrast, a program such as Boston’s “holds to a common set of standards, curriculum, class sizes, ratios, and teacher training. That can really insure high quality consistently,” she said.
More nuanced evaluations of Head Start have also shown different findings, Karoly notes. Head Start’s effects are boosted when the children who attended Head Start are compared to children who otherwise would have been at home (as opposed to the full control group, which includes some children whose parents enrolled their child in a different early-learning program). Head Start is also shown to have benefits for children for whom Spanish is their first language.
Program “fade-out” may also be an issue of convergence, where elementary schools are not able to sustain the gains that preschool students come in with, the report says.
The analysis does suggest that the return-on-investment figures commonly used for preschool, such as a $1 investment creating a $17 return, are overstated. That figure comes from the Perry Preschool research. The city and state programs evaluated in this report mostly show a “return” of $2 to $4 for every dollar invested in high-quality state or city-run preschool right now. Those gains could increase if some of the positive benefits of preschool noted in the first few years after a child leaves the program are sustained over time, the report noted.
The research in this report is also not definitive about the comparative effectiveness of full-day compared to half-day programs, or one year of preschool compared to two. The research suggests that children do see more benefit from more time in preschool, but the benefit is not in proportion to the extra time.
Based on these findings, Karoly said that an important takeaway for policymakers is to start slow. “I would rather see communities investing in quality, starting smaller, and building over time,” she said.
A version of this news article first appeared in the Early Years blog.