Preschool-to-Third Grade Programs and Practices: A Review of Research.

The preschool-to-third grade perspective has helped the early childhood field move away from a reliance on relatively brief or one-shot programs toward more systematic and comprehensive models that span most of children's first decade. We review the knowledge base on the effectiveness of preschool to third grade intervention programs and practices for young children making the transition to school. Our coverage includes extended early childhood interventions, preschool programs, full-day kindergarten, reduced class sizes in the early grades, parent involvement, instructional practices, and school transitions (mobility). We distinguish between two major PK-3 strategies. PK-3 programs are planned interventions that begin during any of the five years of a child's life before kindergarten and which continue up to third grade. The most comprehensive programs include all these elements, and serve children from low-income families or who have special needs. Alternatively, PK-3 practices are defined as specific elements or components of extended early childhood programs that are hypothesized to be associated with children's outcomes. These elements may include preschool education, full-day kindergarten, reduced class sizes, teaching practices, and parent involvement activities. Overall, we find growing evidence for the positive effects of PK-3 programs and practices. The strongest evidence supporting enduring effects into adulthood is from center-based preschool programs followed by small classes in the early grades. Additional longitudinal studies are needed into adulthood to fully document the effects of different PK-3 programs and to verify the extent to which PK-3 practices (e.g., parent involvement, school mobility) have long-term effects into adulthood.