This book resulted from the collaboration of several teachers and scientists, a physician from the Comité Contre les Maladies Respiratoires, experts on atmospheric pollution in the Paris area (including members of the Service de la Protection de l’Air and the Laboratoire d’Hygiène) and teams of fieldworkers from the Maison de l’Air de Paris and the Association Graine de Chimiste. Thanks to their collective work, a series of “air classes” were created, all of which have been evaluated. Readers wishing to learn more about the air we breathe and especially about the problems of atmospheric pollution will find numerous useful tools here including elementary theoretical information about atmospheric pollution and the atmosphere, which can be adapted to the audience being targeted and to the specific pedagogical context. There is also a wide range of practical information illustrated with simple experiments that offer readers a pragmatic, hands-on approach to learning about the physical and chemical properties of the atmosphere and the effects of pollutants and historical information briefly reviewing the evolution of knowledge about atmospheric pollution, the weather and the air. This book also includes a bibliography, a glossary and a list of useful addresses for those who wish to go further. This is an ideal approach, providing fundamental information in an accessible manner in order to develop a civic, preventive attitude.