Things that get me angry: 1/1000 My friend is stuck nearly failing

Things that get me angry: 1/1000
My friend is stuck nearly failing a class that is normally her best subject because she has an incompetant teacher. To avoid ruining her GPA, she tries to get a schedule change to get out of said teacher's class. They refuse her because it's "not a serious enough reason" and then hold her responsible for doing poorly even though she's doing everything she can.
This happens way too often.