These are collections of open access textbooks, 100% free to use, print, or remix. An open textbook is one that has an open license that makes it free for anyone to use and change. It can be print or digital.
The Open Textbook Library is a comprehensive referatory that points to open textbooks by a variety of authors and publishers.
OpenStax is part of Rice University, its mission is to improve educational access and learning for everyone.
The MERLOT system provides access to curated online learning and support materials and content creation tools, led by an international community of educators, learners and researchers.
Directory of Open Access Books
DOAB is a discovery service for peer reviewed open access books and book publishers that indexes and provides access to high quality, open access, peer-reviewed books
Milne Library Publishing at SUNY Geneseo manages and maintains Milne Open Textbooks, a catalog of open textbooks authored and peer-reviewed by SUNY faculty and staff.
OER Commons is a public digital library of open educational resources.
The WAC Clearinghouse provides access to books and books series.All books are available for free viewing and/or download. Many are also available in low-cost print editions.
The Association for Learning Technology (ALT)
This project aims to provide a resource base and supporting technologies to ensure effective support for e-learning professionals.
The American Institute of Mathematics (AIM)
The American Institute of Mathematics (AIM) seeks to encourage the adoption of open source and open access mathematics textbooks. The AIM Editorial Board has developed evaluation criteria to identify the books that are suitable for use in traditional university courses.