“Open Educational Resources (OER) are teaching and learning materials that are freely available online for everyone to use, whether you are an instructor, student, or self-learner. Examples of OER include: full courses, course modules, syllabi, lectures, homework assignments, quizzes, lab and classroom activities, pedagogical materials, games, simulations, and many more resources contained in digital media collections from around the world.” - OER Commons
1) “Cost of College Tuition Has Remained Stable since September 2019.” U.S. Bureau of Labor Statistics, 31 Aug. 2021, https://www.bls.gov/opub/ted/2021/cost-of-college-tuition-has-remained-stable-since-september-2019.htm.
2) “Average Cost of College Textbooks.” EducationData, 12 Aug. 2021, https://educationdata.org/average-cost-of-college-textbooks.
3) Nagle, Cailyn and Vitez, Kaitlyn. "Fixing the Broken Textbook Market: The second edition of a report by U.S. PIRG Education Fund and the Student PIRGS." U.S. PIRG, June 2020, https://uspirg.org/feature/usp/fixing-broken-textbook-market.
OER are free to access online, free to share, free to re-use, and typically are share under a Creative Commons License, allowing others to copy, distribute, or revise the OER for their own purposes.