Open Educational Resources (OER) are teaching and learning materials in the public domain or licensed to give everyone free and ongoing permission to retain, reuse, revise, remix, and redistribute the materials. Open textbooks are a type of OER and a large selection of open textbooks can be found at https://open.umn.edu/opentextbooks. Many MSU Denver faculty are exploring using open textbooks and other OER in courses to enhance the student experience and decrease course material costs. Course with no materials cost (for textbooks, online homework systems, etc.) are starting to be marked with a no-cost for materials designation in the course schedule. Full implementation of this course marking system will be in Fall 2021.