Most states provide pre-kindergarten programs for 3- and/or 4-year-old children. The programs are often for children who might otherwise enter school behind their peers because of life circumstances such as poverty, not speaking English, or identified disability.
Evaluations of pre-K programs have found that they prepare children for success when they enter kindergarten and into later grades. A recent study, however, evaluated the impact of Tennessee’s pre-K program, called the Tennessee Voluntary Prekindergarten Program and did not find these positive outcomes. This study has been interpreted as calling into question the value of pre-K programs in general. The story in North Carolina has been quite different, but first the Tennessee story.
The Tennessee story: The TN-VPK provides full, class-day preschool program across a school year for mostly 4-year-old children who may be at-risk for doing poorly in kindergarten. These classes are taught primarily by certified teachers.
To evaluate the effects of TN-VPK, researchers from Vanderbilt University assessed progress for a group of children enrolled in TN-VPK and a group of children who did not participate in the program. The assessments (of literacy, math and social skills) happened at the beginning and end of the school year and then annually through the end of third grade.
The researchers found that the children who attended TN-VPK scored higher than the non-TN-VPK children on assessments at the end of the pre-K year and barely ahead at the end of the kindergarten year. By the end of third grade, there were few differences between the two groups, with the non-TN-VPK children actually scoring higher on two of the 10 measures collected. The researchers interpret this finding broadly, suggesting that pre-K everywhere is not achieving its goal of preparing children for school, and indeed in Tennessee that appears to be the case.
Better results in N.C.
The North Carolina story: NC pre-K (formerly More at Four) is the pre-K program offered by the state of North Carolina. Like TN-VPK, NC pre-K offers a full-day program during the school year and is taught by a certified teacher.
At the Frank Porter Graham Child Development Institute at the University of North Carolina at Chapel Hill, Ellen Peisner-Feinberg and colleagues have conducted evaluations of NC pre-K for 13 years. In one recent study, they found that at the end of preschool and into kindergarten, children in NC pre-K make significant progress in vocabulary and math, as compared with a norm group. Also, children who had the lowest English proficiency at the beginning of the NC pre-K year benefited the most.
In another study, they found that the reading and math scores at the end of third grade for children were modestly higher for the NC pre-K group as compared to a group who had not attended the program. That is, the effects for NC pre-K do not “fade out” as they had for children in the Tennessee study. Also, for the poorest children, fewer children were identified as having a disability at third grade, as compared to children not attending NC pre-K – that is reducing assignment to special education.
Taking a broader approach with a very different method, Helen Ladd, Clara Muschkin, Yu Bai and Kenneth Dodge from Duke University’s Center for Child and Family Policy come to the same conclusion. They asked whether the children who had been born in a particular county in a year when the state appropriated relatively large funding for that county’s NC pre-K program fared better than children who had been born in a different year or in a different county with lower funding allocations.
More funding, better results
They found that average NC pre-K funding levels improve standardized reading and math scores by an amount equal to several months of learning, for the entire population of children in a county including those who had not been in NC pre-K. That is, the positive impact of NC pre-K spills over to have positive impact on peers, by improving the overall quality of preschool education in North Carolina and by improving the kindergarten readiness of entire classrooms of children so that teachers can teach to a higher level. They find similar positive impact on reducing special education placements and grade retentions, both of which bring large financial savings.
Like the FPG findings, these positive impacts do not fade out during elementary school. The UNC and Duke studies are in agreement, and they sharply contrast the Tennessee findings: NC pre-K yields significant positive impact on children’s educational development.
When researchers come up with different findings, they tend to pick each other’s studies apart. But, let’s assume that the Tennessee and North Carolina studies are all valid: Then, why are there differences between the two states? There could be several reasons.
Tennessee spends about $500 per child less than North Carolina does, which in a class of 18 to 20 translates to a difference in of $8,000 to $10,000 per classroom. Tennessee class sizes are larger (20 children per class as compared to 16 to 18 in North Carolina), and there are more children per teacher (10:1 vs. 9:1 child:teacher ratio). Importantly, in North Carolina, the state has created an early care and education environment, through Smart Start, that focuses on promoting high quality child care for young children and family support. To our knowledge, such a systematic effort does not exist in Tennessee.
Pre-K and other forms of early child care and education are not magic remedies that guarantee success. Pre-K does reduce the disparity between children in need and their peers when they enter kindergarten. But the quality of education and performance of classmates during the years after preschool have effects that may either sustain or squelch momentum from pre-K programs.
North Carolina is consistently higher than Tennessee on state rankings of the quality of public education and students’ performance on the National Assessment of Academic Progress. It may well be that differences in the “sustaining environments” (that is the quality of elementary school instruction and peers’ academic achievement) support the gains made by North Carolina children.
The positive findings from North Carolina are consistent with findings from pre-K programs in other cities and states (Boston, Tulsa, Okla., Georgia, New Jersey). In evaluation research, a single study that has starkly different results from the convergence of finding of other studies is called an “outlier.” When establishing social policy about services and funding, the soundest course is to base decisions on the convergence of findings rather than listening to the outlier.
Samuel L. Odom is professor and director of the Frank Porter Graham Child Development Institute at the University of North Carolina. Kenneth A. Dodge is the William McDougall Professor of Public Policy and director of the Center for Child and Family Policy at Duke University.