We report on an experiment to investigate the effect of an online asynchronous marketing simulation on student engagement and GPA. Engagement was measured in terms of conscious attention, enthused participation and social connection. The participants were 45 students undertaking marketing management at an American university over one semester. Half the students (the treatment group) were required to undertake the simulation in addition to their regular assessments. The results support the idea that online asynchronous marketing simulations contribute to increasing a student's GPA score, and that factors other than engagement may be driving this learning and achievement. Evidence for this included (1) relatively higher post-treatment GPA scores for the treatment group; (2) relatively lower post-treatment levels of enthused participation for the treatment group; (3) lack of significant differences between the groups in terms of conscious attention and social connection.