But it's a question of the function of grades...
Are their purpose to manipulate students into doing particular things?
Should they represent whether a student mastered the material of a course? per the instructor? per the department? per the school? per a universal standard?
Maybe it represents mastery of the methodology of a future career? or the material plus some meta-skills?
Is it a feedback mechanism for students to gauge their own efforts?
Is it a competitive mechanic within the domain of the classroom? within the domain of the school? within society?
A message from an instructor to future employers as to the usefulness of the student?
A semi-competitive sorting mechanism?
A message about the quality of the school? quality of the instructor? challenge of the course?
A single numerical grade would be awkward to combine any two of these into something meaningful. Let alone the significant quantity of these that seem to be a part of the mix.
