For chemistry graduate students who aim to become instructors, intensive teaching training opportunities are valuable but can sometimes be hard to find. Here, we outline our engagement with one such "hidden" teaching opportunity at McMaster University in Hamilton, Canada. In May 2021 and 2022, our student-led team designed and taught "Chemistry in the Art Gallery," a week-long undergraduate course module focused on gallery-relevant atmospheric chemistry and materials science. Because COVID-19 restrictions necessitated remote delivery of our module, we created and mailed lab kits to our students to provide them relevant, experiential learning opportunities through hands-on chemistry activities and assessments that they could complete at home. In this paper, we describe the content we created, evaluate how it was delivered, and discuss ways of expanding the module for integration into other classes. We reflect on our time creating and delivering new course objectives, lectures, activities, and assessments as well as on how this process supported our growth as instructors. Based on our experience, we argue that nontraditional teaching opportunities like this can benefit student instructors by empowering them to meaningfully contribute to educational content, and we encourage their expansion at other institutions.