Perceiving political engagement to be dangerously low among American citizens, many political science professors in recent years have attempted to promote engagement and "healthier" political attitudes. The effectiveness of these efforts appears variable and generally quite modest. Following the model of Canadian citizens' assemblies, we taught a course called Citizens' Assembly on Critical Thinking about the United States (CACTUS) in spring 2008 in which students considered the question: "Is it time to change the way we elect the President of the United States?" Because the course employs a form of deliberative democracy CACTUS might be anticipated to encourage engagement. We use a pre-post survey design to measure attitudes of both CACTUS (treatment group) and other (comparison groups) students to examine this. We find that both CACTUS and students enrolled in other political science courses experienced modest growth in their political engagement. More notably, CACTUS students became more extreme in their party identification, ideology, and issue positions and became more supportive of the existing electoral system. We suspect these findings are attributable to the nature and content of CACTUS. Our findings have important implications for future efforts to promote political engagement and for measuring the effects of those efforts. (Contains 5 tables and 6 notes.)