Due to a resource reorganization at CK-12, the NCLOR needed to re-catalog all the resources available from the CK-12 foundation. The FlexBooks® currently available (72), have now been downloaded to the NCLOR directly in PDF and ePub formats. To view the files you will need a pdf reader or an iOS device, Android device or ePub reader to view the ePub files. All older versions of the resources in the CK-12 series have been archived.

FlexBook® textbooks are CK-12’s open source digital textbooks.

The 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.

Except as otherwise noted, all CK-12 Content is made available to users in accordance with the Creative Commons Attribution-Non-Commercial 3.0 Unported (CC BY-NC 3.0) License (http://creativecommons.org/licenses/by-nc/3.0/), as amended and updated by Creative Commons from time to time (the “CC License”), which is incorporated herein by this reference.

Click on the links below to view the different FlexBook® subjects available in this resource series collection.

FlexBook® Subjects

• Science : Biology (14), Chemistry (4), Earth Science (4), Life Science (4), and Physics (7) 
• Mathematics : Algebra (8), Analysis (3), Calculus (4), Geometry (8), Probability (6), Statistics (6), and Trigonometry (5)
  
• Engineering (3) 
• English (3) 
• Technology (1) 
• Astronomy (1) 
• History (2)
  

The NCCCS courses that these resource may supplement are: AST111,  AST111A,  BIO090,  BIO094,  BIO100,  BIO106,  BIO110,  BIO111,  BIO112,  BIO150,  BIO162,  BIO163,  CHM080,  CHM081,  CHM082,  CHM130,  CHM132,  DFT214,  DMA030,  EGR110,  EGY2000,  ENG125,  ENG126,  EVN110,  HIS131,  JOU110,  MAT121,  MAT122,  MAT142,  MAT223,  MAT252,  MAT263,  MAT271,  PHY101,  PHY110,  PHY121,  and PHY122.

To access these resources, you can do any of the following:

• Click on any of the links above.
• Log into the NCLOR and click on the More button on the left menu bar. Then click the Resource Series link and then CK-12 Flexbooks.
• If you are K-14 faculty, you can add the links to the resources directly to your LMS based course. (learn how)