Teachers with calmer classrooms seem to plan and handle interactions in such a way as to keep aggressive incidents shorter, less frequent, and less intense than in other classrooms and to maintain a low-aggression climate that maintains order and provides a facilitative classroom in which learning can and does occur. Prevention of aggression in the classroom begins with thinking through the classroom demographics, organization, and procedures, all of which may influence students' behavior in school. The teacher should consider the composition of the class, the class members' probable levels of interpersonal and aggression control skills, the classroom's physical characteristics, teaching plans, plans for community building in the classroom, rules and procedures for student behavior, available rewards and sanctions, and efforts to facilitate collaboration between the home and the school. The ideal low-aggression classroom occurs only as a result of hard work by teachers, administrators, other staff members, district offices, parents, other community members, and the students themselves. Sample letters, guidelines, and forms and 13 references