Yes, yes. I can see how my last letter to you seemed far to abstract for your appreciation. I didn’t mean to lose you, but I also didn’t mean to make it easy either. One should always be reaching out to grasp ideas just above our ability to reason well about them. Without this stretching, there could be no growth.
Anyhow, this letter (as per your request) will address one of the more practical aspects of education: grades. Namely, why do we have them? Before going any further, I just want to clarify that I am no expert in the history of grading. I don’t know how we got to our present system nor what other systems may have existed before. However, I do have some thoughts that I want to share.
First, grading is ubiquitous. That is, it is everywhere, not just in education. Health departments routinely give grades to restaurants for their sanitation conditions. The USDA has different grades (reflecting different levels of quality) for meats, cheeses, milks, etc. Schools are often assessed according to a variety of categories, including test scores. Special interest political groups often grade individual politicians on the degree to which they conform to the ideology of the group in question. Even consumer products (like plastics) are graded for their quality.
Second, as can be seen from the examples above, a “grade” is an attempt to quantify that which cannot be quantified. Or, rather, grading is an attempt to use what can be quantified as a way to make decisions about that which cannot be quantified. A grade is an attempt at measurement. But, like all other measurements, grades only have the ability to measure what they have been created to measure. For example, a scale is capable of measuring weight, but it cannot measure health. But often we assume (and there is good evidence for this) that people who weigh more than is reasonable are less healthy than those whose weight is reasonable.
Third, as an objective measure, grading gives important information to the teacher. In teacher jargon, any assignment which is graded is called a “summative assessment.” That is, its goal is to assess (measure) a student’s knowledge and/or skill in a particular area. In doing so, it gives the teacher necessary information about how a student or a class is doing, whether the concepts and skills taught have taken root, and whether that class or student needs additional time with the material.
Fourth, in an ideal world, there would not be grading because each teacher would be responsible for a total of five students. Under this model, the teacher would be able to have a much better and deeper knowledge of a student’s progress, and thus could offer a more qualitative assessment. However, given the reality of the teacher to student ratio, such qualitative assessments are (unfortunately) out of reach.
Fifth, grades, while an important tool of assessment, should not be confused with the aim of education, which is the right ordering of the mind. Grades are a way of seeing how a student is doing, but they are most definitely not the point of education. That would be like saying that the point of going to the doctor is to be a certain weight or height. It might be true that achieving a certain weight is important, but only as a proxy for health.
Anyhow, I hope all of that is helpful!