Class Average on Jacob's cytology test was 83.

Jacob got 80.  Some of the 250 students failed the test.
 There are at least two ways to look at the decrease in class average.
 One obvious reason was the test was harder, or maybe this test
 covered information that the majority of the students
didn't learn in college.

This is what comes up on images for cytology, which is the study of cells.

I would be happy with 80 on a medical school test where the class
average was 83, especially on a test on cells.