Background: One of the essential elements within Sport Education is the inclusion of student roles and responsibilities. While previous research has examined students' performance in officiating tasks, the examination of student-coaches' pedagogical content knowledge (PCK) within peer-assisted tasks of Sport Education has been scarce. Indeed, the only study to date which has examined student-coach effectiveness was conducted by Wallhead and O'Sullivan [2007. "A Didactic Analysis of Content Development During the Peer Teaching Tasks of a Sport Education Season. Physical Education and Sport Pedagogy" 12 (3): 225-243]. In that study, student-coaches struggled to manifest PCK by providing appropriate demonstrations, to diagnose errors, or to modify tasks for higher order content development. The study of PCK may be a useful heuristic to examine instructional effectiveness in physical education. Purpose: The purpose of this study was to examine the evolution of the PCK of a cohort of student-coaches across three hybrid Sport Education-Step Game Approach seasons, and to examine the impact of protocols put in place to specifically enhance coaches' PCK. Participants and setting: Twenty-one students and one teacher from a school class in the north of Portugal participated in the present study. Method: Data from multiple sources were collected: (a) videotape observations of all lessons, (b) field notes, and (c) pre-lesson interviews with the student-coaches. These were then subjected to deductive examination through a process of thematic analysis. Findings and conclusions: Following a baseline season that identified four key limitations within the student-coaches' instruction (task presentation, error diagnosis, feedback, and task modification), these students participated in specific coach preparation that involved modelling teacher's instruction, pre-lesson meetings, and coaches' corners. While showing marked improvement in their content knowledge across the second season, a second protocol was instigated during the third that involved the student-coaches to participate in stimulated reflections of their instruction and the incorporation of planning sheets to enhance their instruction. It was found that both interventions were efficacious in developing student-coaches' PCK, which allowed a more complete transfer of the instructional responsibility from the teacher to the students. These results give insight into the importance of including coach education protocols within the design of seasons of Sport Education with respect to student-coaches' instructional preparation.