Sustainable curriculum design: a comparative analysis of curriculum design methodologies, SDG integration and sustainability competency frameworks in national curriculum policies

Purpose This study examines how curriculum design methodologies – specifically competency-based curriculum (CBC) design and backward design – are represented in relation to the integration of Sustainable Development Goal 4 (SDG 4) and the framing of student sustainability competencies within national curriculum policy at the school level. It identifies structural patterns and divergences across four national education systems. Design/methodology/approach This study adopts a qualitative comparative research design grounded in interpretivist philosophy and an inductive approach. A single researcher read the official national curriculum policy documents and Education for Sustainable Development (ESD) strategy papers from Japan, Finland, the USA and the United Kingdom in full and thematically interpreted them, informed by Constructive Alignment Theory (Biggs, 1996) and Transformational Learning Theory (Mezirow, 1991). Countries were selected to represent contrasting curriculum governance models, ranging from centralised to highly decentralised systems. The analysis focuses on three themes: curriculum design methodology, SDG integration and the framing of student sustainability competencies within policy documents. Findings Competency-based curriculum design and backward design appear, within the documents reviewed, most closely aligned with sustainability goals, learning outcomes and assessment procedures. Japan and Finland, which have centralised national curricula, demonstrate the most consistent policy-level SDG integration and sustainability competency framing. Finland's phenomenon-based, student-centred approach appears associated with the most holistic competency framing across dimensions. The USA and the United Kingdom show more variable implementation, reflecting decentralised and semi-centralised governance, with competency development appearing more dependent on individual teachers and school agencies. These patterns reflect policy orientation rather than measured student outcomes. Research limitations/implications The study relies exclusively on policy-level document analysis and does not capture classroom-level enactment, teacher practice, or empirical student outcome data. All four countries represent developed, high-income education systems, limiting generalisability to developing-country contexts. Thematic analysis was conducted by a single researcher, with interpretation synthesised during writing rather than documented in a separate formal coding log, and no second coder was used, introducing researcher subjectivity as a limitation. Future research should adopt mixed methods, including teacher interviews, classroom observations and student assessments and extend the comparative scope to lower-income education systems and a broader range of stakeholders. Practical implications Policymakers and curriculum designers should embed sustainability competencies as mandatory core learning objectives rather than as optional themes. Competency-based curriculum and backward design frameworks offer replicable models for aligning sustainability outcomes with teaching strategies and assessment. Countries with decentralised systems should consider stronger national coordination mechanisms to reduce inconsistency in SDG integration across schools and states. Teachers should be professionally supported to adopt project-based, activity-based and inquiry-driven pedagogies that actively develop student sustainability competencies at the school level. Originality/value This study makes an original contribution by examining the three-way relationship between curriculum design methodology, SDG integration and student sustainability competencies within a cross-national comparative framework at the school level. Unlike existing literature that focuses predominantly on higher education or single-country contexts, this research provides school-level, document-based evidence and identifies curriculum centralisation as a factor associated with more coherent policy-level ESD framing. The integration of constructive alignment theory and transformational learning theory within a comparative curriculum policy analysis framework offers a lens for future ESD research.