Students enrolled in three levels of general chemistry self-reported their attention decline during both lecture and other teaching approaches via personal response devices (clickers). Students report attention declines of 1 min or less more often than longer attention lapses. The data suggest that student engagement alternates between attention and nonattention in shorter and shorter cycles as lecture proceeds. Introduction of other pedagogies, specifically, clicker questions and demonstrations resulted in significantly lower self-reported student attention decline than lecture. This effect persisted during lectures immediately following the intervening pedagogies. Implications of this research for teaching are discussed. (Contains 6 tables and 1 figure.)