This thesis focuses on topic "ozone in school instruction." The theoretical part approaches the issue ozone from a historical point of view, and chemical as well as physical properties of ozone are being discussed. Furthermore, examples of ozone are being presented, and the predicament of the destruction of the ozone layer and ground-level ozone is briefly touched upon in a separate chapter. In the experimental part of the thesis, a methodological investigation of the issue ozone in the secondary school curriculum is carried out, and subsequently methods for the instruction of this timely topic are being presented. Ozone is a very versatile chemical compound. However, its use generally demands high technical skills and involves high investment costs, which are most likely the reasons for the rare use of ozone. In our society ozone is perceived as relatively dangerous chemical compound. The general public only takes notice of ozone when maximum limits of ground-ozone are being recorded throughout the summer months. The useful properties of ozone, however, are rarely brought to the attention of the people. The ozone layer in the stratosphere protects life on earth from harmful UV rays. Ozone, for instance, can be used in the treatment of drinking water and sewage. A further field of application is the chemical industry, where basic chemicals for industrial processes are manufactured with the aid of ozone. In the paper industry, ozone is increasingly used for bleaching cellulose and additionally, although only on a small scale, ozone is used for odour removal, disinfection and water treatment in aquariums. In chemistry instruction the examples included in the practical part of this thesis could show the effects of ozone in many ways and point to its useful as well as harmful sides. This would consequently allow students to critically engage in the issue of ozone and lead to a differentiated approach to this chemical compound.