Here's a great piece from the NY Times about grades and grading these days. One student puts it this way:
"“If you put in all the effort you have and get a C, what is the point?” he added. “If someone goes to every class and reads every chapter in the book and does everything the teacher asks of them and more, then they should be getting an A like their effort deserves. If your maximum effort can only be average in a teacher’s mind, then something is wrong.”"
At least one commentator suggests that the focus needs to be on capturing the students' interest so that they have in intrinsic motivation to do the work rather than the extrinsic one of grades. But that can be especially hard to achieve in a required class. I'm thinking about these issues right now as I am currently serving on a curriculum review committee charged especially with looking at our first year curriculum, which is where grading complaints are, I think, especially prevalent.
Read the whole thing here: Student Expectations Seen as Causing Grade Disputes - NYTimes.com