Part of an investigation of the effectiveness of Education Consolidation and Improvement Act (ECIA) Chapter 1 reading programs, this document reports on a study of 699 second and fourth grade students in Chapter 1 programs in Iowa. An introduction notes that the study was conducted to discover instructional characteristics that affect student achievement, including kinds and amounts of instruction. It also explains the objectives and management plan of the study. The second and third sections detail the study rationale and design, while a fourth section outlines the instrumentation of the study, including types of instructional time, site selection, and teacher orientation. The fifth section describes results of the study, noting how students and teachers utilized time, and offering structural and contextual Chapter 1 program characteristics. The sixth section, divided into two parts for second and fourth grade students, offers analytical findings. Finally, a discussion section notes that simply increasing instructional time did not improve achievement, that student achievement increased with some time devoted to off-task activities, and that achievement increased, particularly for second graders, when teachers spent adequate amounts of time on organizing and managing the classroom. (Nineteen tables, the Study Observer Handbook, and definitions of variables are included.) (JC)