Gender Differences in Attention Adaptation after an 8-Week FIFA 11(+) for Kids Training Program in Elementary School Children

School-based exercise intervention is recognized as an optimal tool for enhancing attentional performance in healthy school children. However, gender differences in the training adaptation regarding attentional capacities have not been elucidated clearly in the current literature. This study aimed to investigate the effects of an 8-week Fédération Internationale de Football Association (FIFA) 11(+) for Kids training program on attentional performance in schoolboys and girls. Based on a quasi-experimental design, fifty-two children registered in year five of elementary school were assigned into the following groups: training boys (n = 13), training girls (n = 13), control boys (n = 13), and control girls (n = 13). The training groups undertook an 8-week FIFA 11(+) Kids intervention with a training frequency of five times per week, whereas the control groups were deprived of any exercise during the study period. All the participants maintained their regular physical activity and weekly physical education (PE) lessons (two 50-min lessons per week of school curriculum) during the training period. The Chinese version of the Attention Scale for Elementary School Children (ASESC) test was used for attentional assessment at the baseline and one week after the interventional period. The Kruskal–Wallis H test was used for between-group comparison, whereas the Wilcoxon signed-rank test was used for within-group comparison. Significant differences in total scale, focused attention, selective attention, and alternating attention were found in group comparisons (p < 0.001). Furthermore, the training children significantly increased their values in relation to total scale, focused attention, sustained attention, and selective attention (p < 0.05). Only training girls significantly improved their divided attention after the training period (p < 0.001, MD = −0.77, ES = −0.12). In conclusion, the FIFA 11(+) for Kids is an effective school-based exercise intervention for attentional improvement in school children. The schoolgirls demonstrated a positive outcome regarding divided attention after the interventional period.