Just as collaboration strengthens the quality and rigor of our research, it can also strengthen the quality and rigor of our teaching in the development of course materials. Most of us would never hesitate to share data within our research collaborations, so why do we have reservations about sharing teaching materials? In this essay, we argue that the question is not whether educators should use shared teaching materials but how they should use them. The growing availability of shared materials through open educational resources, AI, disciplinary societies, teaching and learning centers, and informal faculty networks reflects a broader shift in teaching. It is tempting to pluck ready-made materials such as handouts, learning activities, rubrics, and test questions wholesale. Using shared materials effectively, however, requires engaging with them critically and adapting them thoughtfully for a specific context in the course design. When approached this way, shared teaching materials become more than a time-saving measure; they serve as effective pedagogical tools. But while they hold the promise of improving classroom experiences, we have observed several potential pitfalls that could lead to unintended and unwanted outcomes.