Children with poor fundamental movement skills might have challenges when engaging in activities that require specific skills to help them perform effectively. Development of those skills through targeted training has the potential to build the foundation for fundamental movement skills. This study examined whether Ki-o-Rahi can enhance learning fundamental movement skills (FMS) and cognitive and social skills in Aotearoa New Zealand children. A quasi-experimental pre-post design was conducted over 8 weeks with 86 primary school children from five separate classes that were allocated to treatment conditions via cluster sampling: two classes to the intervention group, two to the control group, and one to the legend-only control group. The intervention group learned the legend and played Ki-o-Rahi over 8 sessions, whereas the control groups continued with their regular physical activities, but only one of the control groups learned the legend. FMS were measured using the Test of Gross Motor Development—Third Edition (TGMD-3) and the Motor Assessment Battery for Children (MABC-2). Cognitive skills were measured using the Head-Toes-Knees-Shoulders test (HTKS), forward and backward digit span, and forward and backward corsi block. Researchers measured social skills using the Early Childhood Social Relationship with Peers (ECSRP) teacher-proxy questionnaire. The results demonstrated that the intervention and control group gained improvements in the FMS and social skills but not cognitive skills. The legend-only group showed no significant changes. The findings suggest that Ki-o-rahi can contribute to developing FMS, cognitive, and social skills in Aotearoa New Zealand children. Future research should consider extending the duration of the study to assess long-term effects and include a larger cohort of Pacific or Māori children to explore potential benefits of Ki-o-Rahi in greater depth.