Just because its summer doesn’t mean you have to stop learning.

CK-12 Foundation — Flex books are interactive text books that have interactive visuals and practice problems in many subjects. This platform is for students, teachers, and adult learners.
Digital Learn — The Public Library Association has created free digital courses that can teach you everything from computer basics, staying safe online, and becoming more productive. Job skills, online shopping tips, and more.
GCFLearnFree — Tutorials on technology topics, job seeking, design, core skills, and skills for today (e.g. 3-D technology).
Khanacademy — courses from elementary level to AP/College courses. For teachers, parents, and learners.
Wolfram Alpha — Search any topic related to mathematics, science & technology.
LearningExpress Library — Ask for a password to use texshare.net. LearningExpress Library has tests, tutorials, and eBooks for many different learning levels.
OpenStax — Online textbooks for high school and college