<< Background >>In an era, which is characterized by a climate crisis, rapid loss of biodiversity, depletion of natural resources and continuation of global inequalities, it is pertinent to empower especially young people not only to change their thinking but also to change their actions in a progressive and sustainable way. While there is relative global consent, that transformative learning, which focusses on the idea that learners can adjust their thinking and acting based on new information, is necessary for sustainable development, the path towards it is often less clear. Schools need to react to the changing conditions, acting and educating for environmental protection and against climate change. This is not only a challenge for pedagogy but is often combined with processes of redesigning school buildings and yards. As Malinin and Parnell (2012) describe, schools communicate a “hidden curriculum” (p. 12) to teachers, students and the community, which unveils how learning is viewed and which role children and youths play in society. Accordingly it is important not only to work on pedagogy, but to simultaneously pay attention to the design, layout and day-to-day practices of schools. In line with a whole institution approach aspects such as energy consumption, mobility or food choices should be addressed by educational institutions. Accordingly it is important not only to work on pedagogy, but to simultaneously pay attention to the design and layout of schools as well as infrastructure, mobility and food choices.In order to deal with all these challenges, we need schools and educators, that lead by example and try out new, innovative pedagogical approaches in their schools and are willing to make changes to school policy beyond its pedagogy. In this respect, especially All-Day schools show a great potential. The extended time pupils spend at school means more equality between children from high and low income families. Secondly, they offer more extracurricular activities than half day schools, which is important in education for sustainable development (ESD) / transformative education. Furthermore, as children spend more time in this type of school social learning plays a more important role as well. The curricula of many All-Day schools contain numerous topics and educational principles, which are analogous to goals and principles of ESD or just need little adaptation in order to meet these goals. In addition, as students also eat at the school, food choices can be another aspect of a change towards sustainability and climate neutrality. Thus All-Day schools seem well suited to holistically incorporate ESD and transformative learning into their educational programme and to adapt their practice both in the mornings and in the afternoons as well as to the infrastructure and other aspects of school life. Thus, having All-Day schools as a starting point, sustainability education and practices can gradually spread to other social spheres such as families and the general public.<< Objectives >>The aim of our project is to support All-day schools in developing a curriculum as well as day-to-day practices, which foster sustainability education and make an impact toward climate stability. Thus, a major priority in the long term are environmental and climate goals in the sense that pupils are learning about sustainability in order to become active citizens, who are conscious about the environment and our climate and act accordingly. In order to reach this goal, key competences have to be acquired by teachers and pupils alike. Additionally value education, civic engagement and participation lie at the core of sustainability and environmental education and thus are vital ingredients to this project. The project endorses the whole-school approach, integrating ESD / transformative education in a holistic manner. Accordingly, teaching and learning for sustainability is extended to aspects such as community involvement and integrated governance. The whole-school approach further advocates for active, participatory learning (Hargreaves, 2008). In order to do so, this project will learn from existing good-practice examples. Based on these examples, which will be researched through case studies, the project aims at fostering the transformation towards sustainability education and practices by developing in-service training modules for All-Day schools wishing to adapt their programme towards ESD and transformative learning and to change their school policy in accordance with the whole-institution approach.<< Implementation >>Two case studies in All-Day schools will be conducted in each project country. Following the individual analysis of each case,, the next step is a comparative analysis of all cases, focusing on similarities and differences between the project countries and school types. The results will then be used to create teacher-training modules and materials. The development of these will follow an Educational-Design research approach based on researcher-practitioner-design hubs. Based on the idea of involving creative people with different professional backgrounds - partly from the case study institutions and partly from the project partners institutions - as an intellectual core within a design process, this methodology will be adapted to thedevelopment of the teacher training course and materials. Its core, the teacher-practitioner (TP) design hub, will be constituted by representatives of the project partners and collaborates remotely.The TP design hub is involved in every iteration of the design process. Following the development of the course, each partner will conduct one pilot course in their own country, inviting 20 teachers to take part. Through this course, we are supporting educators and head teachers in implementing sustainability measures in their institutions using a whole-school approach. The course will be evaluated by the participating teachers and revised accordingly. The revised course as well as the other project results will be presented at a final conference.<< Results >>The project will produce the following results:• Extensive case study reports from four different countries• Cross case analysis report• Guidelines for the selection and development of training materials• Training material as online documents (text, images) and audiovisual artefacts (eg. podcast, video)• Online course based on MOODLE or a similar online platform, involving synchronous (eg. webinars) and asynchronous communication.Furthermore the project will result in several (scientific) publications and all results will be presented at the final conference. All results will be shared through the project website to reach a broad audience. Through developing and holding a teacher training course, which will also be available as an online training module after the project, we are supporting educators and head teachers in implementing sustainability measures in their institutions using a whole-school approach even beyond the project duration. Additionally, teacher educators as well as educational authorities will profit from the developed course and materials for pre-service as well as in-service training beyond the project.