Math Forum - the Math Forum is a leading center for mathematics and mathematics education on the Internet, with a mission to provide resources, materials, activities, person-to-person interactions, and educational products and services that enrich and support teaching and learning in an increasingly technological world.
MERLOT - Multimedia Educational Resources for Learning and Online Teaching (MERLOT) is a project of California State University and offers peer reviewed online teaching and learning materials.
National Repository of Online Courses (NROC) - a project of the Monterey Institute for Technology and Education, NROC offers full courses, lessons, and learning objects developed by membership institutions that follow lengthy pedagogical guidelines and who are then able to share courses, use others’, and integrate content into their own course management systems.
North Carolina Learning Object Repository - a collection of documents, audio & video clips, learning modules, and more. Subjects include agriculture, engineering, health, language arts, math, and technology.
OER Commons - this site provides a platform on which educators can create or remix open educational resources for lessons and modules. An extensive library includes lesson plans, video/audio lectures, syllabi, textbooks, simulations, and full courses. A section specifically for STEM-related materials is linked to the home page for easy access.
OER Knowledge Cloud - a joint initiative of Athabasca University and the Open University of the Netherlands, this site provides a fully-searchable database for publications pertaining to global OER efforts and developments.
OpenDOAR - the OpenDOAR service provides a quality-assured listing of open access repositories around the world but mainly African institutions.
Open Knowledge Repository - the World Bank's official open access repository for its research outputs and knowledge products.
Open Learning Initiative - The Open Learning Initiative (OLI) is a grant-funded group at Carnegie Mellon University, offering innovative online courses to anyone who wants to learn or teach. Their aim is to create high-quality courses and contribute original research to improve learning and transform higher education.
OpenLearnWorks - supported by The Open University, this website provides a platform where users can create or remix free educational resources, or collaborate with others.
Open of Course - Open of Course publishes only educational information that is open content. Open content makes it possible to share educational information because the licenses explicitly allow that. Licenses one sees here are mainly GPL and Creative Commons licenses, which give users the right to share courses with others, print material, and spread it.
OpenStax - the Connexions Consortium is dedicated to the design and development of collaborative, open educational content that is targeted at supporting education, research and related scholarly activities. The Connexions Consortium is a group of organizations and individuals, including the world's foremost leaders in education, who work together to direct the future development of Connexions and the open education movement.
The Orange Grove - Florida's open educational resource repository. This site includes open courseware, textbooks, 3D models, learning modules, and videos.