Abstract

Environmental Education (EE) at the secondary school level is increasingly expected to do more than deliver ecological knowledge: it must help adolescents develop sustainability competencies, civic agency, and practical problem‑solving capacities aligned with Education for Sustainable Development (ESD). UNESCO’s ESD for 2030 roadmap emphasizes transformative learning that equips learners to address interconnected sustainability challenges. Yet many secondary EE programs remain fragmented, overly content‑heavy, and weakly connected to authentic local problems, decision-making trade‑offs, and measurable competencies. This article synthesizes peer‑reviewed research and authoritative ESD guidance (≤2024) to propose an evidence‑informed strategy set for teaching EE in secondary schools. Using a framework‑synthesis method, we integrate ESD competency frameworks, evidence on effective EE and climate change education interventions, and whole‑school approaches. Results are organized into a Strategy Stack of eight components: competency‑aligned outcomes; place‑based inquiry/outdoor learning; socioscientific issues (SSI) pedagogy; project‑ and design‑based learning; citizen science; service learning; digital systems learning; and whole‑school governance. We translate evidence into practical lesson architectures, assessment rubrics, and an implementation roadmap for secondary schools, highlighting equity safeguards and feasibility constraints.