I found a high school curriculum that looks really good! Easy Peasy All-in-One High School Curriculum was created by a homeschooling dad. The curriculum is faith-based and covers math (here's the free Algebra 1 page, for example), science, history, and Bible courses as well as other courses such as forensics.
And here is the main page to the Easy Peasy All-in-One free homeschool high school curriculum. Look in their right sidebar for the list of courses.
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