Are Two Years Better than One Year? A Propensity Score Analysis of the Impact of Head Start Program Duration on Children's School Performance in Kindergarten

Using data from a nationally representative sample, this study examined Head Start children's school outcome differences by the end of Kindergarten between children who attended Head Start program for two years and the ones who attended for one year. Propensity scores were used to match children who experienced different durations of the program on a series of demographic characteristics in order to achieve a precise estimation of the effects of program duration. The results showed that in comparison to a demographically comparable group of children who attended the Head Start program for one year, the children who experienced two years of intervention services had statistically significantly higher performance on all six academic and social outcome measures by the end of Kindergarten, which included PPVT, Woodcock-Johnson Reading Skills, Woodcock-Johnson Math Reasoning Skills, teacher-reported composite academic skills, preschool learning behaviors, and social skills. Policy and practice implications are discussed. (Contains 3 tables.)