These books have been reviewed by faculty from a variety of colleges and universities to assess their quality. These books can be downloaded for no cost, or printed at low cost. All textbooks are either used at multiple higher education institutions; or affiliated with an institution, scholarly society, or professional organization.

Bookboon.com contains free eBooks and textbooks that can be downloaded as a pdf, no registration needed. These books cannot be altered, but can be freely printed, shared, or embedded in non-commercial ways. They are intended only for individuals, colleges, and schools.

From the University of Bristol, this is one of the world's leading economics education sites, with more than 6000 documents downloaded by human users each day.

MIT OpenCourseWare (OCW) is a web-based publication of virtually all MIT course content. OCW is open and available to the world and is a permanent MIT activity.

Hippocampus offers educators a wide variety of multimedia content online, including videos, animations, and simulations. An additional feature offers educators the ability to create "playlists" for their students, which correlate specifically to their particular instruction material.