The purpose of this study was to investigate the relationship between time-related variables of the physical education lesson and skill concepts acquisition and retention. One hundred and four students aged 6.4 to 7.9 years, and their six physical educators participated. The motor behavior of thirty-six selected students was videotaped during a four-week instruction, and analyzed with Academic Learning Time-Physical Education (ALT-PE) observation instrument (Siedentop, Tousignant, & Parker, 1982). Students were also pre-, post-, and retention tested on overhand throwing and catching concepts by completing a cognitive test. Regression analysis was applied to calculate students' residual acquisition and retention gain scores, and correlation analysis to identify their relationship with ALT-PE categories. Results indicated significant correlations between residual acquisition and retention gain scores in skill concepts and a) "ALT", and b) "student motor engaged". Significantly negative correlations were found between residual acquisition and retention gains and "general content". Moreover, the category "subject matter motor" was significantly correlated with skill concepts learning. It was concluded that time spent in developmentally appropriate skill practice, in contrast to the time spent in activities irrelevant to the instruction's goals, contributes to fundamental skill concept learning. (Contains 3 tables.)