Insufficient sleep is common during high school and associated with adverse developmental and health outcomes. School-based health promotion efforts hold promise for improving student sleep health. This study examines two message strategies, short personal narratives and gain versus loss message framing, in shaping intentions to get healthy sleep and intentions to talk about the information received. We also examine the mediating roles of transportation and positive emotions (happy, content) and negative emotions (fear, anger). We utilize a 2 (narrative vs. non-narrative) by 2 (gain vs. loss framing) between-subjects, randomized experimental design, to test the effect of print messages on these outcomes among a sample of high school students (N = 378). Exposure to the narrative message was directly associated with greater talk intentions but not sleep intentions. Message framing was not directly associated with sleep intentions or talk intentions. Mediation analyses revealed that exposure to the narrative was indirectly associated with sleep intentions and talk intentions via transportation, and indirectly with talk intentions via both participant-reported happiness and fear. Exposure to gain-framed messages was indirectly associated with talk intentions via positive emotion. These findings extend and complicate our understanding of the roles of narrative and equivalence framing in shaping key health promotion outcomes.