Six months ago, I wrote about what I see as the grail of standards-based grading: how to convert rubric scores to standard A-F grades. The best solution, natch, is not to have to convert them at all. If you have the option of reporting your standards-based scores on the report card, then you're golden. The rest of us have to operate with two different ways of grading and reporting. We must number crunch.
I am a bit torn about this search for some mystical tool for converting between the two systems. The concrete-sequential part of me would love to have some sort of simple formula---something that anyone could use and parents/students/counselors could see. I like the idea of something which maintains the integrity of the scores while communicating a single letter grade. The reality, however, is that grading is messy. No matter how many rubrics, standards, and valid assessment tools you have, we are still human beings evaluating the work of other human beings. Reliability is always going to be an issue.
Knowing all of that, I'm still looking for a way to tilt this Quixotic windmill. Here is where my thoughts have led so far.
There is a rough sort of equivalence. If you think about the continuum above, student performance can either be described along an A - F scale or a 4 - 1 scale. If we plot those, then we think about an F as the lowest possible grade and an A the highest. In Standards-based Land, the lowest possible scores are 1's and 2's while the highest are 3's and 4's. I am leaving percentages out of this for two reasons. One is simply that their only purpose is to rank students and that is not the point here. Here, we want to consider an individual's performance. Secondly, percentages don't translate well to an ordinal sort of scale (if you're the kind of teacher who uses 10-point spreads between A - D and a 60-point spread for an F).
Although I don't have the other letter grades plotted here, we might think of them as being evenly spaced along the line. This idea led me to draft the graph shown below.
Here again, things are a bit messy. I chose not to hatch the y-axis because the number of standards evaluated in any given grading period can vary. I think we could safely say that any performance which included no 3's (evidence of standard performance) would be an "F," and student performances of all 3's (or above) would be an "A," but between that, things get interesting. If you're a school which uses + and - along with letter grades, can we use the number of 1's and 2's as a way to distinguish between a C+ and B-?
I have to think some more about the possible practical applications (if any) of a graph like this. Could a teacher, perhaps, use this to develop some sort of algorithm at the end of each grading period? If four standards had been assessed during a given grading period, could you get to a point where two 3's + one 2 + one 1 = C-?
There are different "end users" for grades. I understand that a college will look at a transcript differently than a parent, student, employer, or other teachers. We all see different things in the alphabet soup at that emerges at the end of a reporting period. As a teacher, my most important goal is that students can explain why they have earned the grades that they have---that they know what their grades represent. I don't have any way to have those conversations with the other stakeholders, but I would like to think that we're all more or less on the same page. Maybe that's the real purpose behind the number-crunching.