Events® is a nonprofit dedicated to expanding access to computer science in schools and increasing participation by women and underrepresented youth. Their vision is that every student in every school has the opportunity to learn computer science, just like biology, chemistry or algebra.

Khan Academy: AP®︎/College Computer Science Principles
Khan Academy

This review course includes 800+ practice questions, plus instructional articles and videos covering the topics of digital information, the Internet, cybersecurity, programming, algorithms, simulations, and data analysis.