Educating future scientists and citizens is more effective if students are guided to correctly apply what they learned in school to their daily lives. This experience-based work is focused on the study of a well-known commercial product: cat litter. This material offers different starting points for a critical examination. Questions related to…

Describes a procedure developed by students that measures the mass concentration of particles in a polluted urban atmosphere. Uses a portable fan and filters of various materials. Compares students' data with official data. (DDR)