This article in Science Education discusses a study which used a model of a mixed formal and informal science/technology/society curriculum. The study developed, implemented and assessed collaborative projects using case studies, field trips, and formal class sessions. First, it established constructivist relationships between formal and informal learning activities. Secondly, it developed an innovative, collaborative, project-based approach in environmental education which involved the community at large. Lastly, the study examined the development, implementation, and validation of an integrated formal/informal assessment system that is tailored to the unique learning environment.