Gormley, William T., Jr., and Ted Gayer. 2005. “Promoting School Readiness in Oklahoma: An Evaluation of Tulsa’s Pre-K Program.” Journal of Human Resources 40(3): 533-558.

Since the mid-1990s, three states, including Oklahoma, have established a universal pre-kindergarten (pre-K) program. We analyze the effects of Oklahoma’s universal pre-kindergarten (pre-K) program for four-year-olds on children in Tulsa Public Schools (TPS). The main difficulty with testing the causal impact of a voluntary pre-K program is that certain parents are more likely to select pre-K, and these parents might have other unobservable characteristics that influence the test outcomes of their children. Because TPS administered an identical test in September 2001 to children just beginning pre-K and children just beginning kindergarten, we can compare test outcomes of “old” pre-kindergarten students to test outcomes of “young” kindergarten students who attended pre-K the previous year. We find that the Tulsa pre-K program increases cognitive/knowledge scores by approximately 0.39 standard deviation, motor skills scores by approximately 0.24 standard deviation, and language scores by approximately 0.38 standard deviation. Impacts tend to be largest for Hispanics, followed by blacks, with little impact for whites. Children who qualify for a free lunch have larger impacts than other children.

Both authors are at the Georgetown Public Policy Institute, Georgetown University, Washington, DC, 20057. This work was funded by the Center for Research on Children in the U.S. (CROCUS). The authors thank Jens Ludwig, Deborah Phillips, Ruby Takanishi, Steve Barnett, and three anonymous reviewers for lots of helpful suggestions. They would also like to thank Brittany Dawson, Alexis Lester, Shantay Prince, Emily Sama-Martin, Laura Schiebelhut, Ria Sengupta, Berkeley Smith, and Jean Chung for their invaluable research assistance. The authors greatly appreciate the cooperation they received from the Tulsa Public Schools and the Oklahoma Department of Education. Finally, they would like to thank the Foundation for Child Development, the National Institute for Early Education Research at Rutgers University, and the Pew Charitable Trusts for their generous support. The authors claim full responsibility for the contents of this report. The data used in this article can be obtained October 2005 through September 2008 from Professor William Gormley, Public Policy Institute, Georgetown University, 3520 Prospect St., N.W., Washington, D.C. 20007. E-mail: gormleyw@georgetown.edu.