The purpose of this study was to investigate the effect of instruction differentiation in preventive classroom management strategies on early childhood and elementary preservice teachers' selected behaviors during assigned classroom teaching of music instruction to peers. Participants were early childhood and elementary preservice teachers (N = 7) enrolled in a music integration course at a Midwestern university. This investigation constituted a two-factor within subjects design. The first independent variable was instruction in preventive classroom management which had three conditions: lecture, individual practice, and demonstration practice; the second independent variable was lesson type which had three levels: song/chant, listening, and movement. The dependent variable was the number of selected behaviors (verbal cues, physical proximity, model correct student behavior) displayed by the participants across three eight-minute microteaching sessions. Primary findings included: (a) no statistically significant main effect for treatment condition; (b) a significant main effect for lesson type; (c) a significant main effect for microteaching session; (d) no significant difference among lecture, individual practice, and demonstration practice conditions; (e) a significant difference between listening and movement lessons; (f) no significant difference between song/chant and movement lessons; (g) a significant difference between microteaching session one and three. Anecdotal data and open-ended responses indicated that participants found their participation in this investigation to be beneficial with respect to gaining knowledge of preventive classroom management and experiencing hands-on practice with these strategies. The participants also noted the immediacy and transferability of preventive classroom management strategies to various settings outside of their teacher preparation programs. Results were discussed in terms of (a) limitations of the study; (b) general outcomes; (c) implications and suggestions for future investigations; and (d) considerations for early childhood, elementary, and music education research. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com.bibliotheek.ehb.be/en-US/products/dissertations/individuals.shtml.]