1 School of Psycho-Education, University of Montreal, Montreal, QC H2V 2S9, Canada.
2 School Environment Research Group, University of Montreal, Montreal, QC H3C 3J7, Canada.
3 Montreal Behavioural Medicine Centre (MBMC), Centre Intégré Universitaire de Santé et de Services Sociaux du Nord-de-l'Île-de-Montréal (CIUSSS-NIM), Montreal, QC H4J 1C5, Canada.
4 Department of Health, Kinesiology and Applied Physiology, Concordia University, Montreal, QC H4B 1R6, Canada.
5 Sports Science Unit, Department of Public Health, Experimental and Forensic Medicine, University of Pavia, 27100 Pavia, Italy.
6 Sainte-Justine's Hospital Research Center, Montreal, QC H3T 1C5, Canada.

Active play allows children to develop social and cognitive skills, which could lead to higher school engagement. Little is known about the role of child socioemotional difficulty in these associations. This study aims to examine the interaction between active play and socioemotional difficulty in childhood and their prospective association with academic engagement in adolescence. The participants were 4537 children (51.1% boys) who were longitudinally followed, between ages 6 and 14 years, from the National Longitudinal Study on Children and Youth (NLSCY), Canada. Active play (weekly organized sport and unstructured physical activity outside of school hours) and child behavior (hyperactivity, anxiety, and relational difficulties) were reported by mothers for their children at age 6 years. Academic engagement was self-reported at age 14 years. Unstructured physical activity predicted lower subsequent school engagement for boys (ß = -0.057, p < 0.05). Boys with high anxiety symptoms and high relational aggression who participated in more unstructured physical activity in childhood were subsequently less engaged in school (respectively, ß = -0.066, p < 0.05 and ß = -0.062, p < 0.05). Girls who partook in more organized sports showed lower school engagement in adolescence when they had high anxiety symptoms (ß = -0.067, p < 0.05). Although past studies have highlighted the contribution of active play to school engagement, certain socioemotional difficulties could impede the child's ability to reap its benefits.