Alan Jacobs shares his dissatisfaction with student evaluations:
[F]or a long time I have recommended, to anyone who will listen and to many who will not, that evaluations for a given course be solicited at least one full semester after the course is completed, when students are less emotionally involved in it. A year or more after would be even better. We might get fewer responses, especially from students who have graduated, but they would be better responses.
Whenever I make this suggestion, the first response I get is always the same: “But a semester [or a year] later, they won’t remember anything from the class!”
“That would be something worth knowing,” I reply.