On Friday, I had the opportunity to join the group conducting water testing. For the past four years, the children have been performing chemical and microscopic analyses of the Zagyva River’s water. The work is led by volunteer teacher Terézia Csörgő. Samples are taken from four different locations along the urban branch of the Zagyva at various times and tested for pH, total hardness, carbonate hardness, oxygen levels, and the presence of various ions. In addition to water analysis, microscopic and macroscopic organisms are also examined. The measurement results are recorded continuously, offering intriguing insights. Occasionally, surprising data is obtained, prompting further investigations. Children from all groups participate in these activities, working very diligently and adhering to the rules of chemical testing. As someone with a strong interest in biology and microscopic studies, I found it especially rewarding to work alongside the children. – Anna Horváth, Jászság 1, Semmelweis University