Background: A school-wide program known as Positive Behaviour for Learning (PBL) that systematically reinforces positive behaviours in schools based on the USA model of Positive Behavioral Interventions and Supports (PBIS) but also emphasizes learning processes and outcomes was implemented in the Western Sydney Region (WSR) of Australia. Aim: The study aims to critically compare those schools that implemented PBL (experimental) and those that did not (control) in learning-related psychosocial outcomes. Sample: Third and fifth graders from 4 primary schools implementing PBL (experimental group, n=474) and 2 primary schools which would join the intervention in the following year (control group, n=83) were compared. Method: Confirmatory factor analysis (CFA) was used to validate 9 psychosocial measures: (1) school self-concept (cognitive), (2) school self-concept(affective), (3) English self-concept, (4) mathematics self-concept, (5) parent self-concept, (6) effort goal orientation, (7) planning, (8) study management, and (9) persistence. Then multivariate analysis of variance (MANOVA) tested between-group differences in the 9 measures. Results: CFA found support for the 9 measures. MANOVA found significant between-group differences in (2), (3), (5), and (7), favouring the experimental group. Conclusion: By extending the strength of a positive behaviour support system to include an emphasis on learning processes and outcomes, PBL has made small but important contributions to some psychosocial determinants of student outcomes that may facilitate long-term learning benefits. (Contains 3 tables and 1 figure.)