We assessed the effect of pediatrician-led inservice training on the knowledge and stress of elementary schoolteachers related to attention-deficit/hyperactivity disorder (ADHD). The subjects were 44 schoolteachers staffing a 750-student school. Preintervention and postintervention questionnaires assessed teachers training and knowledge concerning ADHD, teacher stress, and teacher-rated student behavior. The intervention was an ADHD curriculum developed by the national organization, Children and Adults with Attention-Deficit Disorder (CHADD). At preintervention, 41% of the teachers thought that ADHD could be caused by poor parenting and 41%, by sugar or food additives; 64% thought that methylphenidate should be used only as a last resort. Postintervention percentages of teachers holding these beliefs were 7%, 5%, and 34%, respectively. Sixty-one percent had no contact with physicians prescribing stimulants. Teacher stress correlated with ADHD behavior in male students and decreased postintervention. Use of the CHADD curriculum and discussion with a pediatrician were associated with improved teacher knowledge and decreased teacher stress related to ADHD.