This progress report describes a project to institute a school-based health education program with 4th-grade students in an inner-city school district that includes White, Black, and Hispanic families. Project goals are to train elementary school teachers to implement the curriculum; establish a workable research design; and collect multi-dimensional evaluation data on cognitive, behavioral, and biomedical outcomes. The curriculum is oriented toward cancer prevention; objectives include prevention of cigarette smoking and reduction in saturated-fat consumption and obesity. The project is now in the first year of a longitudinal study proposed to follow a cohort of students over five consecutive years. A research design has been established: 15 study schools comprise 48 classrooms with a total of 1500 students, and 8 comparison schools comprise 20 classrooms with a total of 600 students. Data have been collected on health knowledge, health attitudes, snack and exercise patterns, health-related behaviors, and biomedical variables, including serum cholesterol, HDL, and serum thiocyanate. Mean values for these variables, as well as for height, weight, triceps skinfold, blood pressure, and physical fitness, indicate that the study and comparison groups are comparable. The overall prevalence of experimental cigarette smoking among these 4th-grade students is approximately 4 percent (as indicated by serum thiocyanate values). In the coming year the project will continue with the cohort in 5th grade; videotapes will be developed for teacher training; measures of health decisionmaking will be tested; and anti-smoking efforts will be intensified.