Open Educational Resources (OERs) are not just textbooks. You can open up and share your syllabus, a lesson plan, an exercise, a case study, slides, assessment tools or videos you have created on your own. You can also adapt from other Open Educational Resources that are licenced to allow for remixing and adaption, just remember to attribute the original source.
Ryerson supports Pressbooks an on-line open resources creation platform that can be used to create and remix OER. You can request an account by emailing email@example.com; Pressbooks training can also be arranged by contacting Sally Wilson in the Library at firstname.lastname@example.org