Evaluating the Effectiveness of Tennessee's Voluntary Pre-K Program
Pre-k Program (TN-VPK) in attaining its primary objectives of enhancing the school readiness of economically disadvantaged children and improving their academic performance. It will also examine the relationship between student outcomes and selected policy-relevant characteristics of teachers, classrooms, and schools to determine which are associated with the largest effects and thus provide guidance for program improvement. TN-VPK represents a major investment for Tennessee and whether its benefits justify that investment is a matter of some controversy. Many states have undertaken pre-k initiatives with similar expectations, so the results of this study will be of interest beyond Tennessee. Despite widespread belief in the benefits of public pre-k, to date no rigorous evaluation of a statewide public pre-k program has actually been conducted.
Intervention. TN-VPK is a statewide program administered by the Office of Early Learning in the Tennessee Department of Education. It began as a pilot program in 1998 and expanded rapidly after 2005 with legislation that increased its funding. Currently there are over 900 pre-k classrooms in more than 130 school districts across Tennessee. By statute, the program gives priority to four year old students eligible for free and reduced price lunch and, secondarily, to students with disabilities, identified as ELL, or otherwise at-risk. The program in each participating school district must meet standards set by the State Board of Education that require each classroom to have a licensed teacher with a pre-k endorsement, a high adult-student ratio (1:10), a small class size (maximum of 20), and an approved age-appropriate curriculum.
Research methods. Two interleaved research designs will be used to evaluate the TN-VPK program. The first is a randomized experiment encompassing school systems across Tennessee with more eligible applicants than can be accommodated. A sample of these schools will use a lottery to select the children to be enrolled, leaving a randomized control group that will not be admitted and will have access only to the community resources that would be available if there were no TN-VPK program. Grade retention, special education placement, and achievement test outcomes will be obtained from the Department of Education data system. An intensive substudy of this randomized sample will also collect literacy, math, and social-emotional outcome measures annually through the end of third grade when statewide achievement test results are available. Second, a regression-discontinuity design (RDD) that capitalizes on the legally mandated age cutoff for pre-k eligibility will be implemented in 128 representatively sampled classrooms. The same literacy, math, and social-emotional outcome measures used in the randomized study will be collected at the beginning of kindergarten.
The results from the longitudinal randomized experiment will be analyzed with multilevel statistical models to assess the effects of TN-VPK at successive grade levels with particular attention to its impact on third grade state achievement test scores. Moderator analyses will determine whether differential effects are associated with children's gender, ethnicity, baseline scores, or family characteristics. Results from multilevel analysis of the data from the RDD will provide a representative statewide assessment of the effects of TN-VPK classrooms on school readiness at entry to kindergarten, but will be oriented chiefly toward identifying the teacher, classroom, and school variables that are associated with the most positive outcomes (e.g., ECERS, ELLCO, curriculum, teacher background, class size, student mix).