Background: In this article, students' diverse ways of participating in physical education (PE) practice shown in clips on YouTube were investigated. YouTube is the largest user-generated video-sharing website on the Internet, where different video content is presented. The clips on YouTube, as used in this paper, can be seen as a user-generated archive of ongoing PE practices that can enrich our understanding of "how" students participate in PE, as well as "what" they participate in. Purpose: The purpose of the study was to analyse students' diverse ways of participating in PE in order to say something about its practice. Research design: A transactional approach, which takes action in ongoing activities as the point of departure, was used as a theoretical framework, and the sample used consisted of student- and teacher-posted video clips from 285 PE lessons in 27 different countries. Data analysis: In the analysis, students' and teachers' actions-in-ongoing-events were explored in terms of how they participate in the sociocultural practice of PE in terms of students' and teachers' habits-of-action. In the analysis students' and teachers' actions-in-ongoing-events were coded in terms of how they participated in ways that made the situation become stable. Findings: In transactional studies an effort is made to empirically describe and categorise the results of the analysis from the functions the actions constitute in a certain situation. In this study this implied categorising how actions, in the constant flow of actions, contributed to other actions being oriented in a specific direction in a certain situation. Four themes emerged from the analysis: Doing sport, Trying and having fun, Training fitness, and Dancing. Each theme describes how students and teachers participate and how they through their participation shape the content of PE practice. Conclusions: Questions of knowledge in PE can be seen as manifested in students' and teachers' ways of being and acting, as well as their ability to participate in the ongoing PE practices. The consequences of the study indicate that PE and what is regarded as relevant knowledge in PE practice can be constituted in several different ways. PE is about diverse ways of participating, and in this diversity PE is constituted in manifold ways in its practice. These participatory processes contribute to the constitution of PE as a sociocultural practice, and students know PE practice through these processes. (Contains 2 tables and 7 notes.)