To help address this gap, the Head Start CARES demonstration evaluated the implementation and impacts of three interventions that included classroom-based social-emotional strategies, along with professional development (teacher training and coaching) and related supports for scaling up the program, in Head Start classrooms across the country. "The Incredible Years Teacher Training Program" trains teachers to create an organized classroom climate that supports children's behavior regulation (by both the teacher and by the children themselves) and promotes positive teacher-child relationships. "Preschool PATHS" focuses on improving children's social-emotional problem-solving skills, including defining problems and anticipating the consequences of different solutions. "Tools of the Mind-Play" focuses on training teachers to strengthen children's ability to regulate their behavior by using adult-supported, "make believe" play and other activities. The demonstration was conducted with 17 Head Start grantees that varied by geographic location, organizational setting, and size, and generally represented the diversity of Head Start settings nationally. Centers within these 17 grantees were randomly assigned to one of the three interventions or to a "business as usual" control group. This report describes the extent to which each strategy and the professional development supports were implemented as intended, and the degree to which teachers' practices changed as a result. (author abstract)