Background: Enjoyment in sport has emerged as a key psychological factor influencing exercise adherence and cognitive and emotional development. This exploratory study examined pre–post changes in selected cognitive and motor variables over a 15-week observation period and whether average enjoyment during soccer training was associated with cognitive and motor performance indices. Fifty-six players (M = 52; F = 4; age: 9.98 ± 0.70) were observed across 30 soccer training sessions over 15 weeks. Methods: Enjoyment was rated after each session using an emoji-based visual analogue scale, and cognitive performance was assessed before and after the observation period with tablet-based tasks. Results: Pre–post analyses showed significant changes in the Motor Efficiency Test (t55 = 3.15; p = 0.003; Δ = −19.4%; Cohen’s d = 0.42) and FlankTime (W = 1345; p < 0.001; Δ = −8.1%; rank-biserial correlation = 0.68). FlankAcc showed only a nominal, uncorrected distributional change (W = 323; p = 0.015; Δ = 0.0%). Enjoyment was not significantly associated with any of the cognitive or motor performance indices. However, enjoyment scores were clustered toward the upper end of the scale, indicating restricted variability that may have limited the ability to detect associations. Conclusions: These preliminary findings indicate changes in selected cognitive and motor indices over the 15-week observation period, without evidence of direct associations between perceived enjoyment and the cognitive or motor performance indices examined.