Standards-Based Grading

Several of the blogs I read have been discussing Standards-Based Grading (abbreviated SBG) lately.  Perhaps the strongest proponent of this approach as been Mr. Cornally in his blog Think Thank Thunk.

The key ideas of this pedagogic approach seem to be

• Break your course down into the small, testable ideas: the “standards” you will base your grading on.
• Tie every assessment to one or two of the standards, so you know exactly what the assessment is measuring.
• Give the students access to evaluation separately for each standard, so they can see where they need to improve.
• Allow students to reassess on any standard where they are not satisfied with their performance.

The standards passed down from the state for school teachers are far too vague and far too broad to be usable for SBG, so teachers have to come up with their own.  This is probably the main strength and the main weakness of SBG: teachers structure their courses around what they want the students to be able to do, but they get almost no help from textbooks, curriculum committees, and colleagues in designing their courses.

SBG is based on assessments that test only one thing at a time, which is marginally possible in a reductionist view of math, but almost impossible in other subjects.  I’ve thought about applying the ideas to my college courses, which are mainly senior and graduate courses, but I’ve had no success in coming up with assessments.  For example, one topic I teach is Markov chains: I want students to understand them well enough to be able to write a computer program to train a Markov model from data, then use the model to analyze other data.  The assignment I’ve come up with to do this depends on several programming and writing skills (program design, familiarity with the language used, documentation skills, debugging skills, …), in addition to their understanding of Markov chains.  I know no way to separate these skills to test them independently, and weakness in any of the skills can make it difficult to determine ability in the others. Many of the skills I want most for students to acquire are inherently intertwined with other skills.  Being able to program a computer requires algorithm design, data structure design, coding, documenting, and debugging, none of which are easily isolated from the rest, and I’m not interested in the skills in isolation, but in their combination, since I’m teaching a class that assumes the programming skills are already there, rather than teaching them.

SBG requires that students be frequently informed of their progress in each standard.  Since I have had hard time creating assessments that look at only one thing, I have a hard time informing students of what they do and don’t understand.

Reassessment is the aspect of SBG that I have used for years—I allow students to redo any assignment if they are not satisfied with it.  I do hold students to a higher standard on a redo, though.  It is not enough to fix small bugs or grammatical problems that I have pointed out to them—they must show better understanding of the underlying concepts, generally improved writing, or improved programming skills.   This is not quite the reassessment that SBG expects, but SBG assumes that it is easy to generate multiple independent tests for any standard, and that an assessment requires very little time of either the teacher or the student, so that reassessment is cheap.  When the skills to be assessed are complex, a single assessment may take 10–30 hours of teacher time to create and 10–20 hours of student time to do, making reassessment a fairly costly endeavor.

In short, while Standards-Based Grading seems like a good way to structure a course, I’m not convinced that it is feasible for any of the courses I teach, and is probably only applicable to a small fraction of elementary and secondary-school courses.