Classroom management takes account of students and their environment and is intended to increase student achievement by the process of planning, assessment, and evaluation. Reports have indicated that student disruptions may consume much of the instructional time on daily basis. The purpose of this quantitative study was to focus on classroom management self-assessment of middle school teachers and number of discipline referrals written in one academic school year in western part of the U.S. The participants of this study included 237 teachers including 79 teachers at grade 6, 79 teachers at grade 7, and 79 teachers at grade 8 levels. As data collection tool, a questionnaire called Self-Assessment - Classroom Management (SACM) was used and discipline referrals written in one academic school year were collected. The findings the study indicated that teachers, who are inadequate in classroom management, tend to have more disciplinary problems in their classrooms, thus writing more discipline referrals than those who are effective in classroom management.