I'm having some qualms with a professor over a grade I received on an assignment I definitely don't feel (and can prove) that I didn't deserve. If they won't change it, is there anyone above them I can go to to have the assignment re-marked?

Its a third year course, I'm trying to get into Grad school... bad grades definitely don't help with that.

you can probably go to the ombuds office....

http://www.mcmaster.ca/ombuds/

What Gpat said, and don't give up, make that professor regret not being fair.

Definitely go to the OMBUDS office. I've heard from quite a few people that they're super helpful and they'll tell you exactly what to do and such