Classroom management is a common concern for educators. Teachers with high self-efficacy are strongly linked with having successful characteristics regarding their classroom management styles and strategies. With this in mind, the current study examined classroom teachers' perceived self-efficacy, specifically regarding their behavior management strategies, before and after the implementation of school-wide positive behavior supports. Using a multilevel modeling analysis, data collected through the use of self-efficacy surveys from 48 teachers at the secondary level and 15 teachers at the elementary level were examined at the individual and school level. Results indicated that there was an overall increase of self-efficacy in regards to teachers' classroom behavior management strategies. In addition, an interaction effect implied that teachers at the secondary level, with more years of experience, indicated that their self-efficacy lowered, whereas elementary teachers experienced an increase of self-efficacy as a function of the intervention. Implications of these findings and future directions are discussed. [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/en-US/products/dissertations/individuals.shtml.]