The UK faces a growing youth mental health crisis (NHS, 2023; RCPsych 2025). Schools may play a key role in preventing these difficulties from worsening. ​ The integration of nature-based programs (NbPs) into school settings has been proposed as a policy solution to address such mental health challenges but robust evidence is lacking (Lomax et al., 2024), particularly at the secondary school level.​ This Sprint utilised an implementation science framework to co-produce evidence on NbPs in secondary schools with stakeholders including policymakers from the Government’s Department for Education (DfE), young people, and educators. ​ Using a range of methodologies we are evaluating effectiveness, amplifying stakeholder voices, and creating actionable, evidence-based education policy insights.