Because multiple-choice testing is so widespread in higher education, we assessed the quality of items used on classroom tests by carrying out a statistical item analysis. We examined undergraduates' responses to 1198 multiple-choice items on sixteen classroom tests in various disciplines. The mean item discrimination coefficient was +0.25, with more than 30% of items having unsatisfactory coefficients less than +0.20. Of the 3819 distractors, 45% were flawed either because less than 5% of examinees selected them or because their selection was positively rather than negatively correlated with test scores. In three tests, more than 40% of the items had an unsatisfactory discrimination coefficient, and in six tests, more than half of the distractors were flawed. Discriminatory power suffered dramatically when the selection of one or more distractors was positively correlated with test scores, but it was only minimally affected by the presence of distractors that were selected by less than 5% of examinees. Our findings indicate that there is considerable room for improvement in the quality of many multiple-choice tests. We suggest that instructors consider improving the quality of their multiple-choice tests by conducting an item analysis and by modifying distractors that impair the discriminatory power of items. (Contains 5 figures and 4 tables.)