16 OER Sites Every Educator Should Know
Campus Technology provides 16 sites for educators to find quality open educational resource (OER) textbooks and other class materials including practice questions and textbooks adapted for students with disabilities.
These resources could be used as the primary textbook in a course or could be used as supplementary materials available to students. Between the 16 websites, tens of thousands of resources are available for use.
Note: One great OER resource that was not listed can be found here.