Learning principles can be of great value in modifying the behavior of school children. Too often a teacher's own shortcomings and inadequacies hinder him from being truly effective with his students. In general our educational system is based on negative contingencies rather than positive ones. Ways in which a teacher can be more effective in behavior modification include using positive approaches to the reinforcement of desirable behaviors, employing selective attention as a reinforcement, reinforcing the behavior immediately and consistently at first and infrequently after the habit has been established, avoiding inappropriate punishment, and using the principle of shaping to increase by small increments the incidence or strength of a certain desirable behavior. (DE)