Children with ADHD often struggle with executive function (EF) and motor skills, impacting their academics and social life. While medications are commonly used, they have side effects, leading to interest in non-drug treatments. Physical activity (PA) has shown promise in improving cognitive and motor skills in children with ADHD. This study examined the short- and long-term effects of three PA interventions: a specific skill training group (EG1), a low-demand exercise group (EG2), and a control group (CG) over 12 weeks. EG1 showed significant improvements in motor tasks and working memory (15\% improvement, p<0.05), while EG2 and CG showed smaller changes. Long-term PA improved working memory, but short-term PA had limited effects on balance and manual dexterity. These findings suggest that skill training has an immediate impact on motor performance, while more complex motor skills require longer interventions. Smart devices tracked progress, confirming sustained engagement and improvement in EG1. This research highlights PA as a promising non-pharmacological treatment for ADHD, warranting further exploration of its effects on other cognitive domains.