To enable collaborative modeling activities online digital tools are essential. In this pa-per we present a holistic and adaptable concept for the development and implementationof modeling activities – which could especially be fruitful in times of homeschooling anddistance learning. The concept is based on two digital tools: Jupyter Notebooks and a com-munication platform with video conferences.We carried out this concept in the context oftwo types of modeling activities: guided modeling days, where the students work on pre-viously prepared and didactically developed digital learning material, and modeling weeks,in which the students work on open problems from research and industry very freely. Inthis paper the usage of Jupyter Notebook in modeling activities is presented and illustratedwith the example of the optimization of a solar power plant. On top, we share our expe-riences in online modeling activities with high-school students in Germany.