Introduction Social prescribing increasingly includes arts and culture referrals, yet evidence for their effectiveness with children experiencing anxiety remains limited. This study evaluated Culture Dose for Kids (CDK), an eight-week gallery-based community program that represents the type of non-clinical arts intervention social prescribing pathways could refer families to. We examined CDK's effectiveness for children with mild anxiety and their parents through psychodynamic, cognitive behavioural, and developmental frameworks to understand mechanisms that inform social prescribing practice. Method A mixed-methods study was conducted across three NSW sites with 51 parent-child dyads. The study used a randomised controlled trial design with waitlisted controls. Quantitative measures included the Revised Child Anxiety and Depression Scale Parent version and Warwick-Edinburgh Mental Wellbeing Scale. Qualitative data comprised 30 semi-structured interviews and 43 written evaluations. Reflexive thematic analysis was employed, organising findings through three theoretical lenses to understand the program’s beneficial effects. Results Children participating in CDK showed statistically significant short-term anxiety reduction compared to controls. Qualitative findings were organised through three lenses: psychodynamic processes facilitated safe emotional expression and exploration; cognitive-behavioural elements promoted emotional regulation; and developmental aspects strengthened parent-child connections and peer learning. Participants consistently reported increased confidence, resilience, and willingness to try new activities, with benefits extending beyond program sessions. Discussion This research provides evidence for arts-based social prescribing with children and families. CDK represents an effective model of community arts programming that social prescribing services can confidently refer to, demonstrating significant reductions in anxiety and improvements in family wellbeing. The multi-theoretical framework reveals how gallery-based interventions operate across emotional, cognitive, and relational domains simultaneously. Findings support expanding social prescribing pathways to include structured arts programs, offering social prescribing professionals evidence-based options for families experiencing childhood anxiety while strengthening community cultural engagement.