Role-playing simulations are frequently claimed to be effective pedagogical tools in the teaching of international relations (IR); however, there is a surprising lack of empirical evidence on their classroom utility. The assessment of simulations remains mostly anecdotal, and some recent research has found little to no statistically significant improvements in quantitative measures of academic performance among students who participated in them [for example, International Studies Perspectives (2006), vol. 7, pp. 395; International Studies Perspectives (2008), vol. 9, pp. 75–89]. Scant research has been conducted on how role-playing simulations might affect students' perceptions of the instructor's teaching. This paper investigates whether a simulation had statistically significant effect on students' exam scores in an IR course or on student teaching evaluation scores.