The aim of this research was to explore the effects of two approaches, designated as the historical and the contemporary one, on the level of students' understanding of the properties and the practical use of gases. Our research hypothesis was that the historical context of the discovery of gases and the study of their properties would deepen students' understanding of the properties and the practical use of gases more than the contemporary context. A total of 129 students attending the eighth grade of primary school, aged 14, took part in the research project. After taking a pre-test, the students were divided into two groups (A and B respectively), equal in terms of their test scores. Group A (63 students) was exposed to the historical approach, whereas group B (66 students) was exposed to the contemporary approach. The students from group A individually dealt with a text that presented various episodes from the scientific-research work of Joseph Priestley, whereas the students from group B dealt with a text pertaining to the properties and the use of gases in contemporary society. Having been exposed to different approaches, all the students did a post-test. No statistically significant difference was established between the overall results of the students who had been exposed to the historical approach and those exposed to the contemporary approach, and the research hypothesis was rejected. However, one statistically significant better score in one of the post-test items in group A may be connected with the influence of the corresponding episode from the history of science.