This paper reports the use of Rogers' diffusion of innovation perspective to understand the factors affecting educational innovation decisions, specifically in regard to in class electronic response systems. Despite decreasing costs and four decades of research showing strong student support, academic adoption is limited. Using data collected from academic users, non-adopters and other stakeholders reflecting on factors known to affect innovation diffusion, we find issues of cultural compatibility, complexity and relative advantage to be the most critical aspects affecting adoption decisions. These issues partially negate the benefits of increased in class interaction and student engagement. Suggestions for overcoming these issues are discussed.