Provided by the University of Minnesota, this is a searchable catalog of open textbooks for use by faculty.

Open Educational Resources Commons contains full courses, modules, syllabi, lectures, homework assignments, quizzes, lab activities, pedagogical materials, games, simulations, and many more resources contained in digital media collections from around the world.

Multimedia Educational Resource for Learning and Online Teaching (MERLOT) is a free and open peer reviewed collection of online teaching and learning materials and faculty-developed services contributed and used by an international education community.

OpenStax College offers students free textbooks that meet scope and sequence requirements for most courses. These are peer-reviewed texts written by professional content developers.

The Connexions consortium hosts this repository and a content management system. Connexions includes more than 17,000 learning objects in all subject areas.

Collection of open books and textbooks from a variety of sources.

Focuses on undergraduate course textbooks in all subject areas.