Actual constructive criticism can be delivered as it ought to be: to our faces. Any legitimate, substantive complaints can go to the chair or dean. There is no reason for anonymity—after all, we have no way to retaliate against a student for a nasty evaluation, because we can’t even see our evals until students’ grades have been handed in to the registrar (and if you hated us that much, you won’t take our class again). And besides, I hate to tell you this, but professors know handwriting; we recognize patterns of speech; we can glean the sources of grudges. We know who it was anyway.
Even though I have to see the evaluations yet, I suspect the negative evaluations are related to a midterm multiple-choice exam in which the students did below expectations. Rather than the memorization of facts, the correct answers implied a level of analytic skills that many lower division students lack. In previous the semesters the midterm exam consisted exclusively of essay questions, which allowed me latitude in grading them by reading ‘between lines’ the formulation of their ideas and interpolating the intention of their argument when some hints of it was suggested in their comments, but the multiple-choice questions resulted to be a very inflexible evaluating instrument which prevented me of much latitude in grading them.