The paper entitled Social Aspects of Physical Education and Sport in Schools follows the tradition of social research on physical culture, focusing on the evolution of physical education and sport in schools. The subject is analysed using terms and theories that are characteristic of sociology, most notably the sociology of physical culture, historical sociology and the sociology of culture. Individual subsections look at physical education and sport from the angle of cultures and societies, analysing them in the context of their presence in different schooling systems. Questions of physical education and sport in schools are presented with regards to the following concepts: institutionalisation of education, pre-modern societies, developing modern societies, and developed modern societies. In the closing section, the paper discusses the situation of physical education and sport in schools during the final phase of modern societies, including in Poland.