This report describes a research effort and some preliminary findings on effective school practices as they apply to the Portland (Oregon) Public Schools' Education Consolidation and Improvement Act (ECIA) Chapter 1 program, which is a supplementary basic skills instructional program for low-achieving students. Nearly 60 hours of unsystematic observations of teacher practices took place during the 1984-85 school year in the regular reading and mathematics classrooms of 10 Chapter 1 elementary schools. Observations focused on classroom management practices, direct instruction, instructional planning and coordination, and school climate and organization. These observations were supplemented by open-ended interviews with selected teachers and principals. Findings were consistent with those of previous studies. Concluding remarks discuss the findings from an organizational perspective and provide a proposed model for creating schools that can effectively help low-ability students achieve mastery in basic skills. The model identifies the key areas and the proper sequence of school-level interventions that are likely to succeed, as well as variables outside the control of schools that constrain successful change. Although focused on Chapter 1 students, the findings are thought to be applicable to school improvement in general. (RH)