Why do students have to pass an algebra course in order to graduate highschool?
2 answers
Because the state requires it.
Algebra is basic math and every high school graduate should know how to do elementary algebra.
http://www.maa.org/press/periodicals/maa-focus/should-algebra-be-required
http://www.maa.org/press/periodicals/maa-focus/should-algebra-be-required