There are OER (Open Educational Resources) materials, which are resources that are free and open to everyone, everywhere. Then there is ZTC, (Zero Textbook Cost) items, which are resources that are open to students and staff at your institution, but access would be blocked to people outside of your institution. Examples of this would be articles, eBooks, or videos contained in library databases or specific paid subscriptions at your institution.
ZTC sources are great resources and should be used heavily. It isn't technically OER, but the bottom line is, your students already have access to these materials, they won't have to pay for them, and these are great resources to use to keep costs down for your students. Any resources we have in our subscription databases can be added to your courses without any concern for copyright as long as we use links back to the databases.
I can help you find great resources in our databases to include in your classes. Please contact me!
Jeff Wahl, jeffrey.wahl@csuglobal.edu, 720-830-8790