SGA-based volleyball teaching with explicit life skills instruction is associated with technical-tactical, psychosocial, and motivational improvements in school students

This quasi-experimental study examined whether a school volleyball unit based on the Step-Game-Approach model combined with explicit life skills teaching (SGA + LS) was associated with changes in technical-tactical performance, life skills, motivation, and perception of success. Eighty-eight students aged 10–12 years participated in a quasi-experimental repeated-measures design with three groups: SGA + LS, direct instruction, and control. The intervention comprised 18 Physical Education classes. Outcomes were assessed before and/or after the intervention using IAD-VB, Life Skills Scale for Sport, Behavioral Regulation in Sport Questionnaire, and Perception of Success Questionnaire. Generalized Estimating Equations tested group, time, and group×time effects. Significant group × time interactions that remained significant after false discovery rate correction were observed for goal setting, Wald χ²(2) = 11.875, pFDR=0.009, time management, Wald χ²(2) = 10.203, pFDR=0.014, and communication, Wald χ²(2) = 7.538, pFDR=0.044. All technical-tactical outcomes showed significant adjusted interactions, Wald χ²(2) = 10.764–60.676, pFDR≤0.012, with both volleyball-specific conditions showing improvements across several outcomes. At post-test, SGA + LS showed higher decision-making than control, whereas SGA + LS and direct instruction did not differ significantly after Holm adjustment. For motivational regulation, significant adjusted interactions remained for identified regulation, global intrinsic motivation, goal achievement, stimulating experiences, and knowledge mastery, pFDR≤0.021. No adjusted group × time effect was observed for perceptions of success. Overall, the findings indicate selective rather than uniform associations between SGA + LS and technical-tactical, psychosocial, and motivational outcomes in school Physical Education.