Background: Children’s participation in organised sports and other forms of active living usually declines after transition to secondary school. The social network, and digital interventions using the social network, can play a key role in supporting children in active living. This study aims to gather insights into 12–14-year olds’ thoughts on active living and sport participation, motivators and demotivators, the potential role of their social network, and digital interventions. Methods: 26 participants aged 12–14 from different levels of Dutch secondary schools took part in one of five focus group interviews. All interviews were transcribed and analysed using a thematic qualitative approach. Findings: Participants regarded social benefits as strong motivators for active living: being together, making friends, having fun together; however, the social network can also demotivate. Participants were willing to share and hear about positive experiences, descriptive norms, and inspiration for physical activity, but not negative experiences or personal information. In digital interventions, participants stated a preference for social challenges, personalised feedback / goals / activities, and rewards. Competition was seen as less important or even unattractive. Discussion: The research shows that adolescents feel their social network is and can be a strong driver of active living. They are willing to use digital solutions that make use of the social network for physical activity, as long as these solutions involve their current (close) network and uses an approach based on being together and having fun together. This offers possibilities for future digital interventions for active living.