dry grading

When your teacher gives no feedback on your work and just gives you a grade, that's called dry grading.

A: Omg, I really want to be in Professor Hottie's class this semester.

B: He's actually not that good of a professor. I had him last year, and he wouldn't explain why he gave me B's for assignments that I know I deserved an A on.

A: Oh, he's a dry grader?

Dry grading.