Background: Fundamental motor skill proficiency is essential for engagement in sports and physical play and in the development of a healthy lifestyle. Children with motor delays (with and without disabilities) lack the motor skills necessary to participate in games and physical activity, and tend to spend more time as onlookers than do their peers. As such, intervention programs are crucial in promoting motor skill development of children with motor delays. While mastery climate (MC) interventions have shown to positively impact children's motor performance, what is unknown is the impact of cognitive strategies used by children within these climates. Furthermore, although vigorous play seems to be related to the development of gross motor skills, it is still unknown if children with and without disabilities would benefit from exercise play (EP) interventions.Purpose: This study examined the effects of MC and EP interventions on the motor skill development and verbal recall (VR) of children with motor delays. The sample included children with and without disabilities.Research designs: One hundred and thirty-eight children from 27 urban public schools were referred to the present study. Children were assessed using the Test of Gross Motor Development second edition (TGMD-2) and a VR checklist. Sixty-four children (18 with disabilities and 46 without) met the inclusion criteria, which was a score less than the fifth percentile on the TGMD-2. Participants were randomly assigned to the MC or EP 14-week interventions emphasizing gross motor skill practice.Data collection and analysis: Children were assessed at pre- and post-intervention. A 2 (groups)x2 (disability) x 2 (time) analyses of variance with repeated measures on the last factor was conducted. Change scores, t-test comparisons on the delta scores and Cohen's D were also calculated.Results: The MC group demonstrated significant and positive changes over the intervention period. Further, the MC group showed superior locomotor and object control performance and higher recall of verbal cues (p.05) at post-intervention compared to the EP group. Children with and without disabilities within the MC showed similar patterns of improvement. The EP intervention did not demonstrate significant improvements.Conclusion: Children with and without disabilities showed improvements in motor skills and VR when exposed to an MC, incorporating the six TARGET structures. These structures included (a) providing feedback and encouragement, providing opportunities for decision-making and establishing personal goals, (b) including parents in the recognition of children's achievements, (c) creating opportunities to experience leadership and self-pacing, (d) guiding children to use verbal cues and modeling when practicing gross motor skills, and (e) providing demonstrations and teaching children to self-monitor their performance. Instruction is therefore seen as critical to learning gross motor skills, as demonstrated from the findings. Although there were opportunities for vigorous play within the EP intervention, the children did not show improvements in motor performance or VR. These findings suggest that new trends in teacher education physical education to prioritize physical activity over good motor skill instruction may not be advantageous for children in the early years, and should be reconsidered.