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.
Source: The William and Flora Hewlett Foundation
For more definitions of OER, see the Creative Commons Wiki.
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Search all indexed, open access journals
Federated real-time search for OER materials from 21 repositories
Illinois Open Educational Resources including educational and career content
Index of discipline-specific learning materials by California State University system
Searches open content from 79 different sources and contains 324,517 records
Collection of OERs from the SUNY & CUNY project
Peer-reviewed, open license textbooks, hosted by Rice University
Peer-reviewed textbooks provided though the University of Minnesota
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