Four activity days were held during the 2026 Easter holidays. To this end, the physiXS school laboratory visited the holiday care centre of the municipality of Jade on two dates. Together with the children, models were used to examine how dykes should be shaped to prevent flooding even in the event of strong waves. The properties of water were also analysed: What is the significance of surface tension and how can it be utilised? How much salt can be dissolved in water? How can salt water be separated into fresh water and salt and for whom is this important?