This Science, Technology, Engineering, Arts, and Mathematics (STEAM) approach to a lantern hat-making project focused on both the content and pedagogies of guiding high school students to create art through the exploration of multiple connections across different disciplines including visual arts, light physics, mathematics, and geography. A team of educators including two university professors and two high school teachers collaborated to develop a Project-Based Learning (PBL) visual arts lesson adapting the STEAM approach for high school students. The research team implemented this lesson in a high school classroom, observed the students’ learning, assessed their learning outcomes, and reflected on the content and pedagogies of the lessons. Both qualitative and quantitative data were collected and analyzed for this case study. Suggestions and recommendations for developing collaborative high school PBL art lessons using the STEAM approach are provided.