There is increasing recognition of the need to integrate sustainability education (SE) into school curricula, and assessments such as PISA 2025 emphasise the importance of pupils’ ability to apply sustainability knowledge in authentic contexts. Because sustain-ability issues require social, environmental, and economic perspectives, transdisciplinary real-world approaches are recommended. However, many teachers find SE challenging, and initial teacher education (ITE) students often feel unprepared. This study investigates how a transdisciplinary approach can prepare students for sustainability teaching. Fifty-four fourth-year students participated in a two-week transdisciplinary sustainability project. Working in groups, they explored a self-selected local sustainability issue, engaged with community actors, and proposed solutions. The data consist of individual reflection notes describing how the project supported their understanding of transdisciplinarity, authenticity, subject integration, and teacher preparedness, which were analysed using reflexive thematic analysis. Findings indicate that the project strengthened students’ preparedness for sustainability teaching and, through transdisciplinary approaches, offered a concrete model of best practice for SE. Engagement with authentic, local issues fostered emotional involvement, relevance, and deeper understanding, while collaborative work enhanced insight into distinct disciplinary perspectives on SE. Students further emphasised the need for clear subject expectations and strong pedagogical framing.

This study explores changes in university students’ understanding of plastic-related environmental challenges and sustainability competencies following internships. Using a qualitative pre-post design, we analysed questionnaire responses from 16 students who completed six-week internships in Norwegian companies working with plastic challenges. Thematic analysis showed changes in knowledge related to environmental, societal, and economic impacts of marine plastics, and potential solutions and challenges. We identified changes in expressed knowledge related to disciplinary, critical and normative, creative and strategic, systems, and interpersonal and communication competencies. Students primarily demonstrated practice-oriented knowledge, such as familiarity with technologies, sustainability principles and stakeholder engagement, while reflective, ethical, and global dimensions remained less evident in students’ responses. These findings suggest that real-world learning may support the development of applied knowledge and professional skills, while underscoring the need for integrating internships with academic reflection to support competence-related knowledge concerning systemic sustainability challenges. Engagement with authentic sustainability challenges was associated with increased expression of scientific knowledge aligned with scientific literacy, suggesting that internships may serve as learning experiences associated with sustainability competencies. We argue that higher education institutions should strengthen experiential learning and industry collaboration to link theory and practice and prepare students to contribute to sustainability work in practice.