Khan Academy Homework System : Pre-calculus homework materials.
WeBWork: An open-source online homework system for math and sciences courses.
Approved OER Textbooks from the American Institute of Mathematics
“Math in the Modern World” Assignment (CUNY La Guardia Community College)
Resources for Quantitative Literacy Courses by Guertin and Robare (WordPress Doc)
Precalculus Textbooks
Precalculus Textbook, 2017
Apex Calculus, 2015
Highlights of Calculus: Videos by Professor Gilbert Strang, MIT.
Discrete Mathematics