Previous research has shown a reliable association between environmental education and environmentally responsible behavior (ERB). Research has also shown that aspects of religion were associated with ERB. However, the mechanisms of associations are unclear. This study builds on previous research addressing the relationship between student major, religious affiliation, and ERB in two important ways. First, we tested the role of global climate change (GCC) perceptions as a mediating variable in the relationship between major and ERB, and between religious affiliation and ERB. Second, we developed a new measure of ERB focusing on impacts to natural resources. Student major was found to be a significant predictor of participation in ERB, as was religious affiliation. Student major and religious affiliation were also found to be significant predictors of GCC perceptions. The effect of major and religious affiliation on ERB was both mediated by GCC perceptions. (Contains 6 tables.)