Women continue to be under-represented in science fields in Australia and internationally. Efforts to fix the 'leaky pipeline' producing this inequality are frustrated by declining enrolments in higher-level school science subjects. Researchers and policymakers need a better understanding of the factors which influence girls' decisions to take science in senior high school. In this pilot study, we examined whether growth mindset in science, achievement goal orientation, self-efficacy, and perceived peer and teacher support influenced intentions to study senior biology, chemistry, and physics. Participants were 125 adolescent girls aged between 14-17 years living in Australia. Online surveys were used to gather demographic and attitudinal data in a cross-sectional design. Regressions were used to examine the psychological and social factors that predicted subject-selection intentions. Self-efficacy in biology and social support from science teachers positively predicted intentions to study biology. Endorsing a growth mindset in science positively predicted intentions to study chemistry and physics. Self-efficacy for learning chemistry and physics positively predicted intentions to study those subjects. The results suggest that girls who have greater confidence in their ability in science and endorse a growth mindset are more likely to continue their study of physics and chemistry in the senior years of high school.