I found a high school curriculum that looks really good! Easy Peasy All-in-One High School Curriculum was created by a homeschooling mom around 2012. The curriculum is faith-based and covers math, science, history, and Bible courses as well as other courses such as forensics, ACT and SAT prep, and more.
And here is the main page to the Easy Peasy All-in-One free homeschool high school curriculum. Look in the right sidebar for the list of courses.