In an experiment in which students either took quizzes or were permitted to study material repeatedly, students in the study-only group professed an exaggerated confidence, sure that they knew the material well, even though important details already had begun slip-sliding away. The group that took tests on the material, rather than repeatedly reading it, actually did better on a delayed test of their knowledge.
From Rate Your Students:
My classes are large, so I mostly use multiple-choice tests. One day, being one question short of a nice round number, I used this question: "The answer to this question is D. Be sure to mark D on your answer sheet." The offered choices were: (A) This is the wrong answer. (B) This is the wrong answer. (C) This is the wrong answer. (D) This is the correct answer. Be sure to mark it on your answer sheet. (E) This is the wrong answer.
About 20% of the students got it wrong.