One of the most popular definitions of open educational resources (OER), shared by the William and Flora Hewlett Foundation, states that OER “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 re-purposing by others. Open educational resources include full courses, course materials, modules, textbooks, streaming videos, tests, software, and any other tools, materials, or techniques used to support access to knowledge.” Unlike proprietary educational resources, such as textbooks traditionally adopted by state and local educational agencies, OER can be regularly updated and reused in a variety of settings to ensure that instructional materials continue to be relevant for students.