This study was designed to examine the predictive significance of different types and degrees of precocity in preschool children and to assess the effects of participation in a model preschool-kindergarten program operated in conjunction with the study. Extraordinary precocity is defined for this study as performance at the norm for children twice the age of the target child (e.g., third grade reading skill at age four) or performance four or more standard deviations above the mean on a test which permits such estimated scoring (e.g., a Binet IQ of at least 164). Parent questionnaires were also used to identify precocious children. The first section of this report contains a brief history of the project, a first-year progress report, and plans for the future course of the study. The next section includes a description of the sample cohorts, changes in procedures, and data management. Some preliminary findings are presented in the final sections on test-retest reliability, levels of performance, long-term prediction, effects of participation in the model preschool program, patterns of precocity, and school experiences. Extensive appendices describe specific research projects undertaken within the context of the longitudinal study. (JMB)