This study compared the degree to which social networking sites and structured extracurricular activities provided adolescents with positive developmental experiences. Given the relatively unique nature of social networking sites as a leisure context for adolescents, and the extremely fast rate at which this leisure activity has been adopted by the majority of youth in countries where the technology is easily accessible, it is important that research explores how this leisure context compares to more traditional extracurricular activities. Adolescents from eight high schools across the state of Western Australia were surveyed. The results showed that traditional structured leisure activities (e.g., sport, art) provided adolescents with more experiences of identity exploration and reflection and positive peer interactions than social networking site use. Further analysis compared differences within social networking site use and found that both the frequency with which an adolescent visited their social networking site, and the degree of investment they had in their social networking site, positively predicted greater experiences of identity exploration and reflection and positive peer interactions. Though social networking sites are a popular adolescent leisure activity, they do not provide the same level of positive developmental experiences that are afforded through adolescent participation in traditional structured extracurricular activities.