This goal of this study was to develop a quantitative measure that captures the dimensions of youth purpose (intention, engagement, and prosocial reasoning; Damon, Menon, and Bronk, 2003), focusing on students' life goals and aspirations. We tested the construct validity of our new measure using bifactor exploratory structural equation modeling (B ESEM), assuming that the construct of youth purpose may be best measured as a G factor that allows items to freely cross-load in the model (Morin, Arens, & Marsh, 2016). The G factor model was better fitting than a traditional confirmatory factor analysis or ESEM. Additionally the G factor was correlated with aspects of students' civic engagement and mastery components of academic achievement motivation. Suggestions for future research are discussed.