In this meta-analysis, the author analyzed 18 response card articles, theses, or dissertations to determine the magnitude of effect that response card strategies have on test achievement, quiz achievement, class participation, and intervals of off-task behavior. The author also determined whether the type of response cards used or the presence or absence of ceiling effects had a differential effect on study outcomes. Using the traditional method of hand raising as a control condition, he found that response cards have large, statistically significant effect sizes for test achievement, quiz achievement, participation, and reduction in intervals of disruptive behavior. No significant difference was found between types of response cards used. Although the difference was not statistically significant, studies with ceiling effects had, on average, effect sizes that were notably lower than studies without ceiling effects. Place of publication, type of publication, and sample size were not significant moderators of effect sizes for academic achievement. (Contains 5 tables and 5 figures.)