Our project brings together four partner institutions from different geographical regions to strengthen primary school teachers’ competencies in sustainable environmental education. In line with the priorities of Erasmus+ and the UN 2030 Sustainable Development Goals, the project aims to empower teachers with the knowledge, skills, and innovative pedagogical approaches needed to guide students toward becoming active Environmental Citizens. By integrating sustainability principles into daily school life, the project fosters a long-term culture of environmental responsibility within both schools and local communities.