Have you ever had a student approach you after an exam, asserting that the problems on the exam were much harder than the homework you assigned—yet the test problems were taken directly from the homework? (OK, maybe some numbers were changed to protect the innocent, but the problems were essentially the same.) The author suggests a possible explanation for the disparity between students' efforts and the results: The problems in their texts are too well labeled. Although such labeling may be helpful in the instructor's edition when she or he selects representative problems to assign, it may be harmful to the student's ability to determine, unaided, what a specific problem is about.