This report details the outcomes for children enrolled in two types of early intervention programs in Delaware: those serving young children with disabilities and those serving young children living in poverty. The Delaware Early Childhood Longitudinal Study was designed as a retrospective, two-group, posttest-only design. Participating in the study were 717 kindergarten students entering school in the Fall of 1997 in 8 of Delaware's school districts. The sample was stratified according to socioeconomic level and presence of disability, and included 217 kindergartners with active Individualized Education Plans, 250 students qualifying for free lunch at the start of the school year, and 250 students from the general student population who did not have a disability or quality for free lunch. Forty-nine students had received early childhood or Head Start services, and 89 had received preschool special education services. Because only 5 children had received services from the birth-to-3 early intervention system, there was no analysis of this program's impact on child outcomes. Findings revealed that students who received services through the state funded programs, Head Start, or the special education preschool programs showed significantly better academic outcomes than students who did not receive these early intervention services. Children living in poverty who received early childhood education and Head Start services performed better academically 4 years after receiving these services than those children living in poverty who did not participate in the services. Students with disabilities who were identified during their preschool years and who received special services when they were 3 and 4 years old performed better academically 4 years after receiving those services than children who were not identified as needing special education services until they entered kindergarten or later. (Contains 11 references.) (KB)