What is a rubric?

A rubric is a coherent set of criteria for students' work that includes descriptions of levels of performance quality on the criteria. The benefit of using rubrics in formative assessment is that they can be descriptive and not evaluative. Of course, rubrics can be used to evaluate, but the operating principle is you match the performance to the description rather than "judge" it. Thus rubrics are as good or bad as the criteria selected and the descriptions of the levels of performance under each. Effective rubrics have appropriate criteria and well-written descriptions of performance.

What is the purpose of rubrics?

Like any other evaluation tool, rubrics are useful for certain purposes and not for others. The main purpose of rubrics is to assess performances. For some performances, you observe the student in the process of doing something, like explaining discussing procedural rules and evidentiary rules. For other performances, you observe the product that is the result of the student's work, such as memorandums, briefs, substantive legal documents, and litigation documents.

Rubrics give structure to observations. Matching your observations of a student's work to the descriptions in the rubric averts the rush to judgment that can occur in classroom evaluation situations. Instead of judging the performance, the rubric describes the performance. The resulting judgment of quality based on a rubric therefore also contains within it a description of performance that can be used for feedback and teaching. This is different from a judgment of quality from a score or a grade arrived at without a rubric. Judgments without descriptions stop the action in a classroom.