In January 2018 two different large-scale simulation games on the European Union's decision-making process will take place in Brussels. This study aims at bringing systematic empirical evidence from both the EuroSim and the SUNY Model EU, two active learning experiences that gather over 300 international participants, half from the EU and half from US colleges. The intention is to scrutinize whether specific student attributes generate differential effects on the learning outcomes. These involve: a) cognitive outcomes and b) affective outcomes. The first type refers to changes before and after the simulation in the participant's level of knowledge and understanding about the EU policy-making dynamics. The second type reflect upon changes in the participants' overall interest and motivation on the European Union. For analysis, the main explanatory factor of interest is the cultural background of participants; thus, we tackle the importance of the divide between being an EU or a non-EU citizen. The study takes into account other control variables of interest such as age, gender, level of studies, and civic engagement. The main assumptions are tested via a probability survey method based on stratified sampling, which includes a pre-game and a post-game wave. All in all, the results indicate how the effectiveness of active learning environments such as EU simulations do not depend only on the intrinsic characteristics of the game nor on how it is designed but also on the socio-cultural characteristics of the participants.