The Student Climate and Conservation Congress (SC3) is a joint educational effort between the United States Fish and Wildlife Service and the Green Schools Alliance that aims to develop the next generation of conservation leaders through fostering action competence in youth. Data from SC3 participants was used to investigate four predictors of adult environmental behavior (environmental attitudes, locus of control, sense of personal responsibility, intention) to explore their predictability of environmental action and intention toward future involvement in environmental action in student environmental leaders. Of the four variables explored, pre-program levels of environmental attitudes was a significant predictor of environmental action. Additionally, changes in levels of environmental attitudes significantly predicted environmental action, with an increase in environmental attitudes being associated with a decrease in environmental action. Pre-program levels of environmental attitudes and sense of personal responsibility, and an interaction between the two, potentially were predictors of intention toward future involvement in environmental action. Changes in pre- and post-program levels of environmental attitudes, locus of control, and sense of personal responsibility did not significantly predict intention toward future involvement in environmental action, nor did environmental action. Implications for programming and research, in light of the study’s limitations, are discussed.