The CK-12 Foundation was founded with the mission to enable everyone to learn in his or her own way. We pair high quality content with the latest relevant technologies. We equip students, teachers, and parents with everything they need. For free.
CK-12 uses a FlexBook® platform to allow for customization of content and focuses on concept-based learning to allow students to access multiple methods for learning a particular topic.
Meet our team: http://www.ck12.org/about/team/