On the 23.06.2023 the Europa-Universitat Flensburg (EUF) has carried out Offline Multiplier Event at the university. The students have presented their results from the Erasmus+ project CityGo to the public. They carried out the module “Resource-efficient 3D printing” last semester and show their diverse results in the rooms of FabLab IDEENREICH. The openly posed project tasks had the claim to be designed in the context of sustainability, which motivated the participants very much and led to diverse implementations. For around a third of the participating (international) students, it was the first independent 3D print they had created. Others – especially biat students with more previous experience – learned no less and sought their specific challenge, e.g. to create specific spare parts in the automotive sector or for other defective devices and appliances. Another group developed specific clips to enable better cable routing. Erasmus students from France and Spain also participated in the module, so the presentation was in English. In the afternoon, the special organisational framework of the project, which was carried out in an online learning community, was presented and critically discussed. This was followed by joint reflections on how this teaching-learning format could be used for future scenarios – also across institutes.