There are a few key things here that seems to get conflated: 1. Usefulness - Is it a useful thing to study and remember - for an engineer medieval history is u

There are a few key things here that seems to get conflated: 1. Usefulness - Is it a useful thing to study and remember - for an engineer medieval history is utterly useless. 2. Interest - is the student interested in the subject beyond grades and usefulness? 3. Signaling - you need good grades to get to the next stage in your life. 4. Energy and Time - students have other things that they want to do outside of school. Students are making a tradeoff on all these dimensions while optimizing for the grade - this in itself is no easy thing to do.