Background: Many of the issues relating to game performance of students found in the physical education literature can be considered a failure of generalization from practices to games, and from games to games. However, no study in secondary physical education has examined generalization effects as a result of effective game pedagogy in the context of teaching games. Purpose: The purpose of this study was: (a) to examine the effects of technique-focused and tactic-focused instructional conditions on the learning of a tactic by students aged 12-14 years in physical education lessons participating in a tag rugby unit, and (b) to assess the extent to which the performance of this tactic generalized from instructional games to match games. Participants and setting: This study was conducted at an urban middle school (students between 12 and 14 years of age) in the Midwest of the USA. This study was conducted during a 20-day tag rugby instructional unit. Students in three classes participated in the study. Four students from each class were selected to be observed. Intervention: The tactic-focused instructional condition served as an intervention, while technique-focused instruction was used as a baseline. Research design: A multiple baseline design across two classes, with a third class serving as a control, was used to assess the performance of the participants. Data collection: The dependent variable was "supporting movement", which occurred during instructional games and match games. Data were coded for each target student during instructional games and match games using event-recording procedures from observation of a digital-video of the lessons. Coding occurred for each episode for each target student. Each episode ended with any incidence of a pass, tag, score, a ball carrier's error, or if the ball went outside the field of play. When the "supporting movements" met the decided criteria they were coded as correct. Data analysis: Each player's total number of correct "supporting movements" was divided by the number of opportunities for supporting movement and then multiplied by 100 to calculate the percentage of correct supporting movements for each target student. Findings: Low-skilled, female and male students, and average-skilled female students improved their percentage of correct supporting movements after the tactic-focused instruction was implemented. Generalization from instructional games to match games occurred for all students except average-skilled males. Conclusions: Students who typically remain unaffected by instructional interventions improved their performance of supporting behavior during tactic-focused instruction. Furthermore, those students were able to apply a tactic from instructional settings to match games. This study presents an alternative analysis of the conceptualization of sports and tactics. (Contains 8 figures.)