By Rande Iaboni, CNN

(CNN) - A Northampton County, Pennsylvania, judge ruled Thursday against a former Lehigh University graduate student who sued to have her C-plus grade raised and for $1.3 million in damages.

Judge Emil Giordano said there was no breach of contract or discrimination against former student Megan Thode in assigning the grade. Thode, the daughter of Lehigh associate professor Stephen Thode, was attending the university tuition-free in 2009 when she received a C-plus in her master’s fieldwork class.

Lawsuit documents said Thode maintained a B-plus on all written documents, but her instructor, Amanda Carr, gave her a zero in class participation and consequently dropped her grade to a C-plus. The grade prevented her from advancing to the next course required for her degree, although she has since graduated from another program and has a job.

Thode's lawsuit said the professor deprived her of her dream of becoming a licensed professional counselor, and the potential earnings. The lawsuit said Carr retaliated against the student because Thode advocated for same-sex marriage.

The lawsuit also said Nicholas Ladany, the then-director of the degree program, was “personally annoyed and agitated that a female student" would complain about his handling of the grade.

After four days of testimony, Giordano declared that Thode failed to provide sufficient evidence to prove the grade was related to anything but academic performance. He also said Thode failed to present evidence proving that Lehigh, Carr or Ladany engaged in any discriminatory acts toward her.

Thode isn't the first student to sue a school over a grade. In 2007, a University of Massachusetts Amherst student sued in federal court when he received a C, and in 2012, two students at Texas Southern University's Thurgood Marshall School of Law sued because they received Ds. Both cases were dismissed by judges.

Gary Sasso, the dean of Lehigh University's College of Education, said university officials were pleased with the judge’s decision to uphold the faculty’s responsibility to evaluate the work of their students.

“Academic rigor should not be compromised,” he said.

Thode’s attorney was not immediately available for comment.