This case study of a kindergarten boy in the Kamehameha Early Education Program (KEEP) suggests that specific operant training in school-relevant behaviors can facilitate classroom adjustment if the training is coordinated with the regular classroom teacher. The subject, considered unmanageable, hyperactive, and aggressive by the staff at his preschool, enrolled in the KEEP kindergarten and was given simple operant training in a "Staats Box" apparatus. In the Staats Box technique, the child works alone with the teacher outside the classroom. He sits next to a partition containing a slot, through which the teacher (who is visible to him) drops marbles into a jar at appropriate intervals. The target behaviors--sitting, attending, raising hand and making correct verbal responses--were explained to the subject, who was rewarded with a marble each time he responded appropriately to the teacher's questions. Materials used in the training were closely coordinated with the ongoing language experience in the regular classroom. The subject was observed for 20 minutes daily for 10 days prior to the Staats Box sessions, through six days of the training itself, and eight days subsequent to the training. Results indicate that frequencies of the target behaviors in the subject's regular kindergarten class increased both during Staats Box training and after the end of the training, and that the boy successfully adapted to the regular classroom. (CM)