Google CSE: Classroom Resource Repository
This Google Custom Search Engine is currently using the following free websites:
CK12 Flexbooks - http://www.ck12.org/flexbook/
Free Textbooks originating from the California Free Textbook Initiative.
Flat World Knowledge - http://www.flatworldknowledge.com/
Publisher of free and open college textbooks.
Connexions - http://cnx.org/
A place to view and share educational material made of small knowledge chunks called modules that can be organized as courses, books, reports, etc.
OER Commons - http://www.oercommons.org/
OER Commons gathers relevant materials about teaching, technology, research, and more, and encourages you to add links to materials, projects, or news related to the emerging field of Open Education.
Merlot - http://www.merlot.org/
Peer reviewed online teaching and learning materials.
Thinkfinity - http://www.thinkfinity.org/
Easy-to-navigate K-12 resources are grade-specific and are aligned with state standards.
HippoCampus - http://www.hippocampus.org/
The goal of HippoCampus is to provide high-quality, multimedia content on general education subjects to high school and college students free of charge.
Curriki - http://www.curriki.org/
Over 50,000 k-12 learning resources.
MIT Open Courseware - http://ocw.mit.edu/
A web-based publication of virtually all MIT course content. OCW is open and available to the world and is a permanent MIT activity.
Khan Academy - http://www.khanacademy.org/
A library of more than 1,600 video tutorials covering most of the K-12 math curriculum and an increasing number of other subjects.
Creativity Resources for Teachers - http://creativity.denverartmuseum.org/
Making life easier for teachers by providing downloadable art images, reliable information, lesson plans and resources.