In this study, investigators made an experimental comparison of four curricula for Head Start classes: (1) the official (or "traditional") Head Start program, emphasizing enrichment of experience, individual differences, a climate of freedom, and learning by doing, (2) the DARCEE program, emphasizing reinforcement of attitudes combined with training in basic skills and intensive work with mothers, (3) the academic drills approach of Bereiter and Engelmann, emphasizing the ability to handle linguistic and numerical symbols, and (4) the Montessori program, characterized by a high degree of structure in respect to the analysis and sequencing of tasks, combined with great flexibility in that each child is expected to pursue his own interests. During the 1968-69 school year 14 classes were conducted--two Montessori classes, and four classes in each of the other program styles. The 4-year-olds in these classes were pre- and posttested with nine instruments, selected to assess gains in cognitive, motivational, social, and perceptual development. A non-preschool control group was also tested. Classes were monitored periodically throughout the year to assess treatment dimensions. All phases of the first year of this study are now complete. Data analysis is in process. Tables and appendices are included. (Author/NH)