Comprehensive Guide to the Best Free Open Educational Resources for Online Learning

Open Educational Resources (OER) are learning materials that are free, either because they are in the public domain or have been specifically created with an open license. Open resources allow anyone to legally use, adapt, and share them for free, giving students all over the world access to high-quality learning materials. OERs can include textbooks, syllabi, lecture notes, videos, assignments, projects, and tests.

See the list below for a range of sources for high-quality OERs including entire courses, textbooks, and ebooks.

OER Courses

CK12 offers free, comprehensive learning materials for students from kindergarten through college. The organization aims to enable students to learn at their own pace in the way that is most effective for them. Resources include customizable textbooks, study guides, videos, interactive simulations, and practice exercises that adapt to students’ skill level.

MIT’s OpenCourseWear is a collection of material from thousands of MIT courses, especially in science, technology, engineering, and math, aimed at high school students. Students can use the resources on the site to get help with their homework, study for tests, prepare for AP exams, and work on projects.

MERLOT, founded by the California State University’s Center for Distributed Learning, develops and distributes learning materials like presentations, drill practices, videos, simulations, learning modules, and even entire course curriculums.

The Utah Education Network, established by the state’s Board of Education, provides material for parents, teachers, and students developed by university faculty, district and school specialists, teachers, and USBE staff. Textbooks and interactive games are available for students PreK through college in subjects like English Language Arts, Math, Science, and Social Studies.

Boundless offers open-source courses in 22 different subject areas in a range of difficulty levels, from basic algebra to college-level economics. Each course package contains reading materials, PowerPoint lecture slides, and tests.

Curriki creates and aggregates free and open resources including lessons, videos, and worksheets with the goal of using technology to reduce the so-called “education divide”—the gap between students who have access to high-quality education and those who do not.

The Mathematics Vision Project was created by team of educators and provides material for six courses (Secondary Mathematics I, II, and III; Algebra I and II; and Geometry), with honors options available for all courses. The materials allow students to follow curriculum themselves at their own pace.

OER Textbooks

Wikibooks, a Wikimedia project, is a collection of open-content nonfiction books, especially textbooks. With more than 3,000 textbooks, students can find materials on just about any subject, including math, science, social sciences, humanities, and foreign languages. Wikibooks also has a sub-collection of texts for younger children up to age 12, called Wikijunior.

Openstax, founded by Rice University, is one of the most widely-used open-content textbook repositories for higher education—nearly 500 colleges and universities have adopted an Openstax text. Books are available in five different formats, including a printer-friendly version.

Free Ebooks

The Open Textbook Library provides a catalog of free, peer-reviewed, and open-licensed textbooks with the aim of reducing costs for college students, who often spend thousands on textbooks each year. Each of the collection’s 700+ textbooks are used at or affiliated with institutions of higher education.

The Online Books Page from the University of Pennsylvania facilitates access to free books on the internet. The site has an index of 2 million free online books, information about large directories of online books, and exhibits highlighting special categories of books, like banned, prize-winning, and female-authored books.

The State University of New York’s Open Textbooks site offers open-license textbooks and courses written and curated by SUNY Faculty.

Bibliomania is a collection of free online literature, including more than 2000 classics. Study guides are available for selected texts.

The Directory of Open Access Books contains thousands of academic, peer-reviewed books uploaded by publishers, available for free download or purchase. You can browse by subject or use the search function to find texts relating to specific topics.

HathiTrust is the largest collection of digitized books and a collaboration of academic and research libraries. It features texts in the public domain, which are available to view for free, and a searchable catalog of copyrighted texts.

The Internet Archive includes a digital library offering over 20 million books and texts for free download and 1.4 million modern books that can be borrowed for 2-week periods. Through partnerships with libraries and other institutions around the world, the Internet Archive has content available in 184 languages.

Planet eBook offers free classic literary works that are in the public domain in multiple formats, including mobile-friendly and e-reader formats.

Project Gutenberg is an online library of over 60,000 free eBooks, available to read online or to download as Kindle or epub files. The site focuses on older works for which U.S. copyright has expired.