ABSTRACT: This research investigated the effects of a nutrition education program on dietary behavior and nutrition knowledge among elementary school—aged children participating in a Social Cognitive Theory—based nutrition education program. Participants included 1100 second-grade and third-grade students selected by convenience-type sampling from public schools in Alabama. A preassessment and postassessment control group design assessed dietary behavior and nutrition knowledge using Pizza Please, a specially designed interactive evaluation tool. A 2 × 2 mixed analysis of variance was used to analyze data. Children in the treatment group exhibited significantly (p < .001) greater improvement in overall dietary behaviors such as consumption of dairy products, fruits, and vegetables, than children in the control group. Children in the treatment group exhibited significantly (p < .001) greater improvement in nutrition knowledge, including Food Guide Pyramid understanding, nutrient-food association, and nutrient-job association, than children in the control group. Results suggest that nutrition education programs that teach positive dietary messages potentially can improve dietary behavior and increase nutrition knowledge in children.