Abstract Zoological parks, nature centers, natural history museums, and related institutions are valuable resources for urban environmental education in developing countries. To determine the effectiveness of conservation education strategies currently in use at such institutions in Colombia, the authors implemented and compared several program formats. A zoo workshop in wildlife conservation targeting elementary school teachers was designed, evaluated, and contrasted with existing programs, including a zoo visit preceded by a slide show, an unstructured visit to the zoo, and a control group. The authors assessed responses from 1,015 fourth-grade students in 26 randomly selected schools in Cali, Colombia. Students in the four experimental groups completed a pretreatment and a posttreatment questionnaire comprising an achievement test with 18 multiple-choice knowledge questions and a 16-statement, 5-point attitude scale. Test results indicated that knowledge and attitude scores of students whose teachers p...