This study compared a cognitive-behavioural, solution focused (CB-SF) coaching intervention and a positive psychology intervention (PPI) utilising a randomised control trial design. PPIs are described as volitional activities focused on enhancing well-being and promoting flourishing through helping people to change their feelings, behaviours, and/or cognitions drawn from the science of positive psychology, whereas CB-SF coaching is construed as the application of specified psychological knowledge within a goal-focused coaching process. To date, there has been no research that compares the impact of coaching and positive psychology programs in the same study. The purpose of this research was to compare the relative effectiveness of CB-SF coaching and PPIs with adolescents in a school context. Seventy-three (73) Senior High School (Year 11) students (male and female) were recruited from two selective high schools in Sydney, NSW, Australia. Participants were randomly assigned to one of three conditions for ten weeks. The first group received CB-SF coaching, the second group received a PPI, while the third group was a “Well-being as Usual” control group. Compared with CB-SF coaching, participation in the PPI led to increases in mental well-being, although these findings were less pronounced at a nine-month follow-up time point. The CB-SF coaching was associated with increased academic goal striving compared to the PPI and Controls post intervention however gains were not maintained at the nine-month follow-up time point. Trends for the variables of depression, stress, and cognitive hardiness were in the expected directions, although effects were not statistically significant. Overall findings suggest that both types of proactive mental health interventions have great potential to contribute to the well-being and academic goal-striving of an adolescent population, although more research is warranted.