Music plays a major part in many people’s life, especially during the teenage years where adolescents often make a conscious choice to invest time and money into music (or not) and music might become an important part of their identity. However, still little is known about how musical abilities grow during the years between 10 and 20 and where differences in the individual musical abilities come from and how they interact the growing of intelligence and other cognitive resources. To answer these questions the talk will present findings from the LongGold study (longgold.org) that is tracking the development of secondary school students in the UK and Germany over time. We will show how musicality has positive associations with cognitive skills and growth mindset attitudes and how we might encourage these positive developments.