The implementation of a comprehensive reform model for early childhood programs, Curiosity Corner, developed by the Success For All Foundation at the request of the New Jersey Department of Education, is evaluated in this study. The program was implemented in 27 child care and preschool classes in 4 high poverty urban areas and outcomes were compared to those of 23 matched control classes. In observations of classroom environment quality using the Early Childhood Environment Rating Scale, Curiosity Corner classes received higher ratings than controls. The language abilities, as measured by the Mullen Scales of Early Learning, of 316 three- and four-year-olds who participated for 1 year in either an experimental or control class were also compared. The expressive language abilities of children in Curiosity Corner classes for 3-year-olds were significantly higher than those of children in control classes. There were no differences in children's receptive language or visual reception. Children in classes with higher quality ratings showed better performance on the expressive language subscale. (Contains 16 references.) (Author/EV)