The links below are to moderate-to-advanced sites that are for independent learning or practice drills. While we cannot endorse or attest to the quality or contents of the links below, the list includes several sites we have used and would consider using or recommending to students — particularly to students who wish to continue learning in a supplemental, independent format.
Coding Practice Sites
Coding Tutorial Sites
has over 100 CS-related Courses — linked below are some titles that looked particularly well suited to the high school courses. NOTE: edX courses are online adaptation versions of college courses and would be expected to be presented at levels suitable for teacher PD or advanced students.