As we mark a decade since the adoption of the Sustainable Development Goals (SDGs) in 2015, fostering a sustainable mindset in the next generation has become a critical focus for educational systems worldwide, with an emphasis on education for sustainable development (ESD). This paper presents best practices from the Erasmus+ “Developing a Sustainable Mind-Set” (SysMind) project, which integrates sustainability content and competencies into secondary school curricula to cultivate environmental and social responsibility among students. This multi-country initiative (spanning Austria, Turkey, North Macedonia, Latvia, Spain, and Ukraine) embeds sustainability topics across different subject areas, thereby weaving these themes and competencies into everyday learning and demonstrating a model for holistic curriculum integration.
