How best to prepare physical education students for their first teaching experience is still debatable. This research specifically addresses the issue of lesson preparation. The effects of planning on teachers’ behaviors have been examined in the past (e.g., Peterson, Marx, & Clark, 1978). Imwold et al. (1984) found that planning had an effect on teaching behavior when comparing teachers who planned their lessons to those who did not. Twardy and Yerg (1987) concluded that planning promoted active teaching behaviors among teachers. In the same vein, the present research studied the effects of lesson planning on the behaviors of teachers and students under two planning conditions: a) self-made (SM), and b) ready-made (RM) lesson plans. Following the same lesson objectives, RM plans were given to preservice teachers one week prior to their teaching day whereas SM lessons had been planned by the preservice teachers. An alternating treatment design was used to examine 18 physical education majors who had no previous teaching experience as they taught soccer and volleyball units to 3rd grade students. Teaching episodes were videotaped and assessed using an ALT-PE based instrument. Visual analysis of the graphic data was used to analyze the relationship between planning conditions and behaviors. No significant differences between planning conditions with regard to student waiting and cognitive or teacher verbal instruction were found. However, significant differences were found in favor of SM lesson plans with regard to student motor-appropriate and off-task behavior. Similar to Byra and Coulon (1994), these results indicated that engagement in planning has a positive effect on the students’ behaviors of preservice teachers. When preservice teachers used their own plans, their teaching was more successful in maximizing time students were engaged in a motor-appropriate activity and in minimizing time they were engaged in an off-task behavior. As opposed to other studies which investigated the effects of planning versus non-planning by preservice teachers, this study utilized nationally validated SPARK curriculum as the source for RM plans in addition to preservice teachers’ SM plans. Nevertheless, the SM lesson plans produced better teaching practices. The main recommendation for teacher educators was to provide preservice teachers with more SM planning opportunities in order to encourage better teaching practices during preparation programs. Future research should examine preservice teachers’ affective domain in order to complement the findings of this study and demonstrate how the planning process affects preservice teachers’ feelings, thoughts and beliefs.Keyword(s): professional preparation