The purpose of this study was to evaluate the effectiveness of teacher modifications of environmental demands in the classroom to improve social skills and the effectiveness of coping in preschool children attending Head Start. The intervention program was derived from the Coping Frame of Reference, a set of theoretically based practical guidelines for improving coping effectiveness in children. Coping was facilitated by creating a goodness of fit in the classroom between environmental demands and a child's ability to manage them. This was accomplished by grading and modifying physical, social, and activity demands so that they were congruent with the child's capabilities. The intervention program was ten weeks in duration, and included the following components: (1) teacher training in modifying demands in the classroom to promote goodness of fit; (2) teacher modifications of demands on a daily basis in the classroom; and (3) weekly consultation sessions with teachers to collaborate in selecting weekly classroom interventions. The participants were 60 to 80 predominantly Latino children and their teachers from four classrooms in two Head Start sites. Two classrooms were assigned to receive the intervention program and two classrooms served as controls. A quasi-experimental, non-equivalent group design was used with pre-test and post-test comparisons made between the intervention and control groups on measures of coping effectiveness and social skills. Process evaluation included identification of environmental modifications used in the classroom, and their frequency of application by the teachers. The results of the study: (1) provided information about the coping behaviors of the child participants and their responsiveness to changes in environmental demands; and (2) contributed knowledge about specific methods and strategies that can be used preventively to promote coping with stress and demands in the classroom, and to improve coping in children whose behaviors are ineffective in managing demands of the environment.