To review and synthesize the literature on interventions to facilitate shared decision-making or to increase participation in decision-making in pediatrics focusing on interventions for children and adolescents. We systematically searched three electronic databases (September 2021, update in September 2022). We included studies that aimed to increase involvement of children and adolescents in medical or treatment decisions, regardless of study design and reported outcomes. Study quality was assessed using the MMAT. The synthesis strategy followed a narrative methodology. 21 studies met the inclusion criteria. Interventions aimed to increase participation by provision of information, encouraging active participation and collaboration. Didactic strategies included digital interactive applications (n = 12), treatment protocols and guiding questions (n = 12), questionnaires or quizzes about patients' condition or their knowledge (n = 8), visual aids (n = 4), and educational courses (n = 1). Findings indicate positive effects on some of the investigated outcomes. However, the heterogeneity of studies made it difficult to draw consistent conclusions about the effectiveness of interventions. Interventions used a variety of approaches to facilitate SDM and increase participation. The findings suggest that interventions have inconsistent effects across different outcome variables. The evidence was limited due to the methodological shortcomings of the included studies. To increase the participation of children and adolescents in decision-making, interventions targeting them are needed. Most intervention focus on the provision of information and encouragement for active participation. The results suggest high feasibility and, mostly, positive effects in participation, health-related knowledge, patient-HCP relationship, and adherence The study highlights that further high-quality studies using similar outcome parameters are needed to investigate the effects of interventions to facilitate participation in decision-making.