Development of mature fundamental movement skills (FMS) is shaped by both biological (secular trends) and socio-cultural influences (e.g., Title IX). The gradual lowering of the age of entry into adolescence alongside increased opportunities for children to participate in school or community based sports indicates a need for current information on FMS development. The purpose of this study was to examine developmental change associated with mature kicking by children in grades k-8. This study addressed the following research questions: (a) What are the characteristics of individual differences in kicking development over time? (b) Are differences in developmental growth trajectories of mature kicking systematically related to age, sex, or participation in sports? The basic design for this study was multicohort longitudinal. This design enabled us to examine the influence of age, sex and sports participation while reducing cohort effects. Following a pilot study to determine interrater reliability, we tested children's performance on the kicking subtest of the Ohio State University Scale of Intra Gross Motor Assessment (OSU-SIGMA). Specifically, we tested four cohorts of boys and girls in grades K-8 (N=340) from 1992-2000: 1992=K-8, 1994=2-8, 1996=4-8, 1998=6-8. In 2000 we again tested the original kindergarten cohort. The resulting data was analyzed by Hierarchical Linear Modeling (HLM). This technique uses slopes and intercepts of children's performances to establish individual growth trajectories. Predictor variables (age, sex, sports participation) were then added to the model to provide a clearer understanding of mature kicking development. The principal findings were: (a) significant (p<.05) differences were observed in mean initial status (intercept) and growth rate (slope) for the K-8 and 4-8 cohorts; (b) no sex differences were observed among any of the cohorts in either initial status or growth rate; and (c) significant (p<.05) results were noted for sport participation; that is, children who participated in organized soccer at the time testing were more likely to exhibit mature kicking form. In the final analysis, boys and girls were similar in terms of initial status and rate of kicking development and benefited equally from participation in organized soccer.Keyword(s): elementary education, physical activity, research