Open textbooks are the most common form of OER and exist in a variety of disciplines. While some disciplines make up the majority of the open textbooks that exist, more and more are being published every day. The big names in repositories for open textbooks are: OpenStax, Open Textbook Library, LibreTexts, BC Campus, and OER Commons.
Open textbooks are one way to significantly reduce student textbook costs and eradicate barriers to equal access of information. While the majority of open textbooks are "born digital" because of their licensing through Creative Commons there is no charge to print pages or create altered physical copies.
Learn more about open textbooks through the webinars, videos, and links below.
Ancillary materials are materials like test banks, quizzes, powerpoints, homework, etc. that tend to come with commercially published textbooks. Some OER like Openstax textbooks come with a pretty basic package of ancillary materials, but a lot of open textbooks do not. This is an area of OER that is steadily growing but still falls short in some disciplines. There are some good sites to search for ancillary materials, but there's also the option to create too!
Search for Ancillary Materials:
OER should be evaluated the same way you would evaluate any resource for your course, taking into consideration the content, the ease with which the ideas are presented, and the ability of it to meet your course needs. In addition, when evaluating OER you will also want to consider how it can be presented and accessed by your students. But, the beauty of OER is that you are free to adapt and remix it to meet your needs!
You can find the PDF versions of each below.
As with any resource that isn't yours, be sure to give credit where credit is due! You can use the Open Washington Attribution Builder (CC BY 4.0) to help you select the best attribution for your OER.
Open Washington also has a self-paced workshop available freely on their site here. This workshop will take you through 10 modules, providing a great introduction to OERs.
Finally, two major OER sites, Open Textbook Library and MERLOT, engage in peer review of materials.