What questions and conversations do 3-way multi-level blended STEM teaching partnerships generate? Participating college faculty reflect on their scholarly teaching of cooperative problem-based learning designed to empower college STEM majors to foster development of scientific habits of mind in young students. Themes include mentoring techniques, feedback mechanisms, and emerging signature pedagogies for this type of college internship experience. In the service learning partnership explored in this session, college interns teach a semester-long inquiry-based enrichment program which places 5th graders in the role of science sleuths. Science faculty teach pedagogy to their college interns while partnering with them to design pedagogy, labs, and science mysteries based on the specifications, formative, and summative feedback from elementary teachers. The college interns guide their 5th grade students to generate hypotheses, perform experiments to test these hypotheses, interpret lab results, and propose a solution to a science mystery based on their results. The faculty panel will engage in interactive reflection with the audience exploring questions and emergent themes based on summaries of stakeholder surveys and focus groups. Lessons learned from this teaching and learning experience will be presented in an interactive format designed to explore generalizability and pose new questions in the ongoing research