The Heart Healthy Program in a health education project developed for elementary school students. It was designed to (1) increase their consumption of complex carbohydrates, and decrease their consumption of saturated fat, cholesterol, sodium, and sugar; (2) increase their level of habitual physical activity; and (3) generalize these changes to other family members. The overall program and 12 class lessons were designed using informative instruction, participatory classroom activities, personal goal setting, parent handouts, feedback, and reinforcement. The program was evaluated using a time-series experimental design with all students in three 4th grade classes at School 1 and three 5th grade classes at School 2. Evaluation was conducted using direct observation of eating and activity, as well as paper-and-pencil assessments of knowledge and attitude. Results indicated substantial changes in eating behavior at school, knowledge about heart health, food preferences, and family eating patterns as reported by parents. Observed changes in exercise were minimal during treatment, and were related to seasonal sports activities at follow-up. Eating habit changes persisted over a four-month follow-up which spanned summer vacation. These outcomes suggest that school programs developed using specific techniques can be effective in facilitating important behavior changes at school and at home.