Textbooks and materials can be expensive. If you're interested in ways to ease the financial burden for your students and offer high quality learning materials that are available anywhere, and enjoy the ability to customize learning materials to your own courses, Open Educational Resources or OER are worth investigating.
Open Educational Resources (OERs) are teaching, learning, and research resources that reside in the public domain or have been released under an intellectual property license that permits their free use and repurposing by others. OER include full courses, course materials, modules, textbooks, streaming videos, tests, software, and any other tools, materials, or techniques used to support access to knowledge. (From the William and Flora Hewitt Foundation)
The terms "open content" and "open educational resources" describe any copyrightable work (traditionally excluding software, which is described by other terms like "open source") that is licensed in a manner that provides users with free and perpetual permission to engage in the 5R activities:
Retain - the right to make, own, and control copies of the content (e.g., download, duplicate, store, and manage)
Reuse - the right to use the content in a wide range of ways (e.g., in a class, in a study group, on a website, in a video)
Revise - the right to adapt, adjust, modify, or alter the content itself (e.g., translate the content into another language)
Remix - the right to combine the original or revised content with other material to create something new (e.g., incorporate the content into a mashup)
Redistribute - the right to share copies of the original content, your revisions, or your remixes with others (e.g., give a copy of the content to a friend) (This material was created by David Wiley and published freely under a Creative Commons Attribution 4.0 license at http://opencontent.org/definition/)
OER Mythbusting - SPARC dispels the myths associated with Open Educational Resources at https://sparcopen.org/our-work/oer-mythbusting/