Chain Reaction in Germany was implemented as professional development (PD) project. Starting each year by a PD course the Chain Reaction philosophy, aims and model have been introduced, and the teachers were familiarized with six selected Earth and Universe Pupil Research Briefs (EUPRB), which were given as the practical basis of the IBSE approach. The chosen EUPRBs did match the German curricula regarding content and research focus. The teachers have been adapting these ideas to their own scenarios and their specific school conditions. They delivered student-focused lessons using the EUPRBs or complementing it. Using critical thinking and problem-solving skills, students at secondary level have been working within scientific scenarios they have been personally interested in. Their work has been published via posters and oral presentations that have been shared on the school site as well as on national “Express Yourself Conferences.” These annual conferences celebrated science and the work of the students. In this chapter, challenges, opportunities, activities, and results are reported.