I recently took many Khan Academy math, calculus, trig, etc. courses to brush up.
Khan Academy is absolutely outstanding. He makes very complex subjects easy to understand.
Rooster (or anyone familiar with Khan), how is the history? Is it typical revisionist, fabrication or ignore facts like history is taught today?
Khan is good for individual subjects and lessons and it is free but doesn’t provide a curriculum and some of us need more structured guidance to meet standards required to earn credits
For math up to high school I like IXL math (subscription but worth it) and also Discovery Education Streaming (subscription but worth it) for all subjects, especially social studies, science and language arts
Home School Buyers Co-Op (free) offers discounted subscriptions to many resources