Teaching in a public school is a demanding job as the multiple dynamics of a classroom can be a challenge. In addition to addressing the challenging behaviors that many students without disabilities exhibit, more and more students with emotional and behavioral disorders (EBD) are being included in the general education classroom. Effective instruction and the development of effective instructional environments have been demonstrated to decrease problem behaviors in students with histories of failure in school. Positive behavior support (PBS) provides a framework for considering development of instructional environments that increase the teacher's ability to deliver effective instruction to all students, thereby increasing success rates and reducing negative behavior across the school. The same PBS features: prediction, prevention, consistency, and evaluation apply in the classroom to decrease the number of problem behaviors and increase academic and social success. This paper presents a description of the key features of effective classroom PBS and demonstrates each via the use of case examples. The premise of PBS is that the more effectively the environment is designed, more effective it can be in facilitating classrooms that run smoothly and efficiently, allowing teachers to recognize, assess, and plan for students with special needs.