The aim of the present study was to investigate the effects of various scheduled practices (self-regulated and non-self-regulated) on the acquisition, retention and transfer of simple and complex tracking tasks. 96 right-handed undergraduate students (age rang: 18-24 years old) volunteered to participate in this study (48 females, 48 males). These students participated in physical education classes (1 & 2) in their first semester of 1387-88. Participants were assigned to one of eight different groups (n=12), which differed in types of tasks performed (simple tracking or complex tracking) and the practice schedule used (blocked, random, self-regulated, or yoked). The method was quasi-experimental. These tasks were designed as software and appeared on a computer monitor. The movement time and movement error (click) were assigned as scores in different groups. After the pretest, the subjects practiced 8 16-trial blocks in 2 sessions. 24 hours later, they participated in the retention and transfer tests. The data were analyzed by mixed factorial ANOVA and Bonferroni post hoc test. The results showed a significant difference between various scheduled practices and type of task in various stages of movement time (P<0.05) (i.e. the effect of contextual interference in the acquisition and retention of movement time of tracking tasks was observed). Meanwhile, there was no significant difference between various scheduled practices and type of tasks in various phases of movement error (click). The differences were not significant in transfer test, but the self-regulated groups showed the most improved performance in various phases of test. These findings suggest the effectiveness of contextual interference and they show that self-regulated practice is an important variable for scheduled practice.