OER stands for Open Educational Resources, and OA stands for Open Access. While there are some important distinctions between the two (namely, you can modify and redistribute OER), in the context of online learning, both OER and OA materials are free to read and share with your colleagues and classes.
These types of resources are a great choice for online teaching because they do not require a Touro College sign-in, so they ensure access is continuous and all but guaranteed.
The Touro College Libraries staff can help you find OER and OA to use in your courses, but this page also had some resources to get you started.
Teaching Commons: includes OER from colleges and universities and is curated by librarians and participating institutions
epubBooks.com: free public domain eBooks that you can download in the EPUB format.
Google Books: Previews and full-text ebooks. Full-text books are out of copyright, or books in which Google received permission from the publisher to reproduce.
Hathi Trust Digital Library: a repository providing access to public domain and in-copyright content from a variety of sources, including Google, the Internet Archive, Microsoft, and in-house partner institution initiatives.
Internet Archive: Ebooks and Texts Archive: contains a wide range of fiction, popular books, children's books, historical texts, and academic books.
Project Gutenberg: first and largest single collection of free ebooks that are out of copyright in the United States.
PLOS (Public Library of Science): open access e-journals in science and medicine.
NCBI Bookshelf: free online access to ebooks and documents in life sciences and healthcare.
Open Textbook Library: 700+ open textbooks
OAPEN Library: Open Access Publishing in European Networks (OAPEN) Library contains freely accessible academic books, mainly in the area of humanities and social sciences.
BioMed Central: part of Springer/Nature, BMC publishes open access journals in science and medicine.
Open Book Publishers: freely-available ebooks and e-textbooks in the Humanities and Social Sciences.
Project Muse: open access e-journals and ebooks from university presses and scholarly societies.
DOAB (Directory of Open Access Books): collection of peer-reviewed open access ebooks.
DOAJ (Directory of Open Access Journals): collection of peer-reviewed open access e-journals.
Mason OER Metafinder: provides a real-time, simultaneous search of 21 different sources for open educational resources.
LibriVox: free audiobooks in the public domain to enjoy or contribute to.