The program activities, curriculum, and evaluation of the Pennsylvania Research in Infant Development and Education (PRIDE) Project are described in this report. The project is an educational effort to accelerate the development of children, 12-52 months of age, by providing developmentally enriching experiences in a controlled environment which enhances the growth of sensory, conceptual, and language abilities. Four principal components constitute the PRIDE Project: (1) The Center Early Learning Program, (2) The Home Early Learning Program, (3) The Cognitively Oriented Prekindergarten, and (4) The Parent Involvement Program. The Center Early Learning Program is the primary component of the PRIDE Project and consists of a 2-year sequence, beginning at the first level with a group of children between 12 and 20 months of age, with participating children being brought to the center each weekday for developmental sessions with a teacher and aides. The Home Early Learning Program consists of a 2-year sequence with children 12 to 20 months of age, in which children are visited in their homes by individual tutors. The Cognitively Oriented Prekindergarten forms the third year of the center-based preschool programming and involves children previously enrolled in the Center and Home Early Learning Programs. The final component, the Parent Involvement Program, provides instruction to disadvantaged mothers in children's health care and mental development. Each of these components is discussed and evaluated in this report. (CS)