This paper relates to students' productive disciplinary engagement (PDE) within the teaching of gymnastics in Tunisia. Students' engagement is investigated from the pragmatist and social-interactionist perspective of the didactic joint action framework in conjunction with productive disciplinary engagement. Data were collected through ethnographic observations using video recordings and teacher interviews during a 12th grade gymnastics unit conducted by a female teacher in a senior high school. Analyses of students' actions were carried out during significant episodes when they worked without the direct presence of the teacher. The study draws attention to how breaches of the didactic contract initiated by students promote knowledge content development and how students contribute to the situated didactic process. The analyses of students' contrasted cases (two high-skilled, two low-skilled students) highlight how students actively participate in shaping their learning. The discussion points out some generic patterns that keep students engaged in a PDE. The paper is concluded with a consideration of the utility of the two theoretical frameworks for understanding student learning in physical education lessons.