CK-12 Foundation is a non-profit organization with a mission to reduce the cost
of textbook materials for the K-12 market both in the U.S. and worldwide. Using
an open-content, web-based collaborative model termed the "FlexBook," CK-12
intends to pioneer the generation and distribution of high quality educational
content that will serve both as core text as well as provide an adaptive
environment for learning.
Free tools and resources for educators support collaborative student-centered learning. Online thinking tools are active learning places where students engage in robust discussions, pursue investigations, analyze complex information, and solve problems