The objectives of the present study were to develop and evaluate out-of-school water environmental education programs for four different river weirs in Korea. Contents of textbooks for elementary and middle school students related to water environments was analyzed. New out-of-school water environmental education programs were developed for four different river weirs, which was practice-based, from the results. When the out-of-school environmental education programs were applied, they were evaluated by the participant students. The middle school students had better understanding about water resource management technologies than the elementary school students. However, the recognition of the elementary school students to the importance of water management was higher compared to the middle school students. The survey results showed that the developed programs were well constructed and helped improve the understanding of the water environment.