A work in progress, CK-12's Algebra I Second Edition is a clear presentation of algebra for the high school student. Topics include: Equations and Functions, Real Numbers, Equations of Lines, Solving Systems of Equations and Quadratic Equations.

CK-12's Texas Instruments Algebra I Student Edition Flexbook allows students to better utilize a graphing calculator in understanding the fundamental concepts of algebra.

CK-12's Texas Instruments Algebra I Teacher's Edition Flexbook allows an Instructor to teach students to better utilize a graphing calculator in understanding the fundamental concepts of algebra.

CK-12 Foundation's Algebra I Teacher's Edition FlexBook complements CK-12's Algebra I Student Edition. The solution and assessment guides are available upon request.

CK-12 Foundation's Basic Algebra FlexBook is an introduction to the algebraic topics of functions, equations, and graphs for middle-school and high-school students.

CK-12 Algebra Explorations is a hands-on series of activities that guides students from Pre-K to Grade 7 through algebraic concepts.

CK-12 Foundation's Algebra FlexBook is an introduction to algebraic concepts for the high school student. Topics include: Equations & Functions, Real Numbers, Equations of Lines, Solving Systems of Equations & Quadratic Equations.

This guide is for faculty authors, librarians, project managers and others who are involved in the production of open textbooks in higher education and K-12. Content includes a checklist for getting started, publishing program case studies, textbook organization and elements, writing resources and an overview of useful tools.

CK-12 Basic Physics - Second Edition updates CK-12 Basic Physics and is intended to be used as one small part of a multifaceted strategy to teach physics conceptually and mathematically.

The Basic Speller is a spelling program for beginning students and consists of eight volumes of 48 lessons each. It presents lessons and practice for learning the relationships between sounds and their spellings.

The Basic Speller is a spelling program for beginning students and consists of eight volumes of 48 lessons each. It presents lessons and practice for learning the relationships between sounds and their spellings.

There has been a lot of talk about free online resources but this is the first I have seen that involved anything having to do with FREE digital textbooks. Had to share!

Submitted as part of the California Learning Resource Network (CLRN) Phase 3 Digital Textbook Initiative (CA DTI3), CK-12 Advanced Probability and Statistics introduces students to basic topics in statistics and probability but finishes with the rigorous topics an advanced placement course requires. Includes visualizations of data, introduction to probability, discrete probability distribution, normal distribution, planning and conducting a study, sampling distributions, hypothesis testing, regression and correlation, Chi-Square, analysis of variance, and non-parametric statistics.

This textbook covers Algebra II and Trigonometry topics with chapters on equations and inequalities, linear equations and functions, systems of linear equations and inequalities, matrices, quadratic functions and more.

CK-12 Foundation's Algebra FlexBook is an introduction to algebraic concepts for the high school student. Topics include: Equations & Functions, Real Numbers, Equations of Lines, Solving Systems of Equations & Quadratic Equations.

Submitted as part of the California Learning Resource Network (CLRN) Phase 3 Digital Textbook Initiative (CA DTI3), CK-12 Foundation’s high school Biology FlexBook covers cell biology, genetics, evolution, ecology, botany, zoology, and physiology. This digital textbook was reviewed for its alignment with California content standards.

This book is a "flexed" version of CK-12's Basic Geometry that aligns with College Access Geometry and contains embedded literacy supports. It covers the essentials of geometry for the high school student.