Every semester, colleges and universities ask students to complete innumerable course and teaching evaluation questionnaires to evaluate the learning and teaching in courses they have taken. For many universities it is a requirement that all courses be evaluated every semester. The laudable rationale is that the feedback provided will enable instructors to improve their teaching and the curriculum, thus enhancing the quality of student learning.

In spite of this there is little evidence that it does improve the quality of teaching and learning. Ratings only improve if the...