Many, many open educational resources have already been developed and made available online. Indeed, one challenge with OERs is the sheer number. We hope the following lists will provide a helpful entry point into the world of OERs. The following includes a range of materials, including syllabi, test banks, class exercises, simulations, videos, ebooks, and more. Note that the "open" part of some of these resources may need to be evaluated on a case-by-case basis. Always look for licensing and copyright statements for each resource (just to be sure!).
The Mason OER Metafinder allows you to search a variety of sources simultaneously, including the Library of Congress, Project Gutenberg, Open Textbook Library, OER Commons, OpenStax, Internet Archive, Project Gutenberg, MERLOT, and Hathitrust.