Radioactivity is usually associated with something negative, such as reactor accidents. In the Science Lab Radioactivity, however, we would like to focus on natural radioactivity. The ambient air, rainwater and tap water contain decay products of radon, this can vary greatly depending on the region. So the students examine their direct environment. But distance, shielding and deflection laws can also be determined. For this purpose, a button radiator is available as a natural source of radiation. The number of pulses is recorded with the Mobile-CASSY 2 WLAN and the GM Adapter M.