In this informally-written news article ("her professor ... awarded her a big, fat zero for classroom participation") a student is suing her (always a her) university for breach of contract and sexual discrimination because she was given a C+.
As a university professor, no one has made me aware of any "contract" that promises the student a particular degree. But I've had plenty of students who begin finals week by letting me know what grade they "need" to graduate. Like I have a standard I'm supposed to meet. "You gave me a C, but I thought I told you I needed a B. Go back and try harder!"
The problem starts with terminology; students don't receive grades, they earn them. I don't give them a grade, I do the calculating to determine the grade they have earned for themselves. This student has demonstrated a complete inability to function in the modern world without favoritism and privilege (and an inability to perform a proper cost-benefit analysis; she shouldn't be compensated for the entirety of her foregone wages, only what would be in excess of her second-choice profession--which her finance professor father should know).