textbook
CK-12: Free, quality math and science curriculum
This site features textbooks in a flexible format called "Flexbooks" available for free download and printing. Most programs include a Teacher's Edition, workbooks, and other supplementary material, all for free. The topics at the moment include middle school and high school level math and science. The science is mainstream (evolution is included in Life Science and Biology programs). The Chemistry course includes labs. The math is fairly traditional and includes Algebra, Geometry, Trigonometry, Probability & Statistics (AP), and Calculus (AB). Free S