STEM teachers play a key role in attracting pupils to STEM subjects via engaging, real-world classroom practices, which naturally involve interdisciplinary problem solving, inquiry and/or design. However, STEM teachers are not trained to implement such practices. In order for secondary STEM education to better represent real-world practices, STEM teachers need to be schooled in an interdisciplinary way in parallel to their discipline-specific pedagogical schooling. Furthermore, as one of the primary providers of digitally competent workforce, STEM education should pave the way for the accelerated transformation towards a more digital world. Future STEM teachers as well as their teacher educators must be prepared to take on that challenge. This project aims to engage teacher educators and researchers in investigating and developing efficient means and materials to immerse student STEM teachers in interdisciplinary cooperation, problem solving, and content creation via 100% online learning opportunities.This online training must prepare future STEM teachers for coaching pupils in high-quality integrated STEM (iSTEM) education with a sufficient amount of cross-disciplinary competence and self-efficacy. Having student teachers cooperate in multidisciplinary teams to design and implement iSTEM learning units is a powerful strategy to achieve this objective. However, how this training strategy can be implemented effectively in purely online training is yet to be explored. Therefore, teacher educators and researchers will work together in this project to prepare and develop a rich online learning environment that supports the student teachers in their online, interdisciplinary, team-regulated (and team-paced) learning (including problem solving, design, and implementation of iSTEM learning units). We will first construct a report on key competences of effective (i)STEM teachers (IO1), based on our national teaching contexts and current gaps in teacher education programmes, European and scientific publications, and societal challenges. Guided by these key competences, we will develop online training and coaching materials (IO2), and an online platform (IO4), including scaffolding questions, guidelines, tools, applications, e-assessment, and features supporting the student teachers in their online cooperative, interdisciplinary learning. The training materials and features of this whole online learning environment will be tailored to (1) the targeted key competences, (2) suggestions from research literature on the desired training strategy, (3) the scaffolding needs of the student teachers detected during the first project year. The online platform and training materials will be developed and refined via iteration during two successive academic years. We will develop and implement an instrument (IO3) to assess student teachers’ learning gains from this online training with respect to the targeted key competences. The digital iSTEM learning units designed by the student teachers as part of the online training (IO5) will be made openly available for pre- and in-service STEM teachers to use with their pupils.This project will be realised through cross-fertilization and collaboration of five partners in the field of higher education:- For exploring, developing, and field testing evidence-based digital training materials that will scaffold the online learning environment:> the academic STEM teacher education department of KU Leuven, with 9 campuses across Belgium, brings its expertise in effective iSTEM pedagogies and curriculum design, and in research-based pre-service upper secondary STEM teacher training;> the STEM teacher education department of University College of Northern Denmark brings its expertise in competence-, inquiry- and ICT-based pre-service lower secondary STEM teacher training; and> the Ágoston Trefort Centre for Engineering Education of Óbuda University in Hungary brings its expertise in development of e-learning materials, in coaching and mentorship in upper secondary technical/vocational STEM teacher training.- For developing the online platform that will provide the frame of the online learning environment:> the Software Engineering and Internet Technologies Laboratory of the computer science department of the University of Cyprus brings its expertise in design and programming of state-of-the-art educational technologies and digital materials.- For disseminating the project results:> SEFI brings its expertise in networking, and communication and its large network in the field of engineering education.This partnership hopes to propagate its enthusiasm towards the professional field and the research community, and to create awareness of the crucial role of interdisciplinary STEM teacher training. In the long term, we hope to see the effect of the online training reflected in an increased number of STEM-literate, motivated pupils taking up higher STEM study programmes or STEM careers.