It is commonly claimed that outdoor adventure programmes produce positive changes in participants by exposing them to adventure activities designed to encourage self-discovery and character building. Previous studies have focused on the impact of rehabilitative adventure therapy programmes and adventure education programmes for male dominated or co-ed environments, however little is known about girls' motivations for participating in adventure educational programmes and their associated outcomes. The purpose of this study was to examine the effectiveness of a five-day Outward Bound course among young, female secondary students in Singapore. A total of 149 female students aged from 13 to 16 years from a single cohort took part in the study. Results showed that the course had positive impacts on the participants' social skills, interpersonal skills, leadership, and self-esteem. The effect sizes ranged from 0.24 to 0.64, which were consistent with the moderate change of previous outdoor programmes effect size research (Hattie, Marsh, Neill, & Richards, 1997). In addition, intrinsic motivation positively predicted participants' satisfaction level after the course. Overall, this study showed that outdoor adventure programmes can have a positive impact on adolescent Singaporean girls.