This is one of a series of reports which provide definitions of and descriptive data on the variables used in the Comparative Study of Phase IV of the Individually Guided Education (IEG) Evaluation Project. Phase IV investigated three curriculum programs specifically designed to be compatible with instructional programming for the individual student: (1) the Wisconsin Design for Reading Skills Development (WDRSD); (2) Developing Mathematic Processes (DMP); and (3) Prereading Skills (PRS). Information on instructional methods and pupil outcomes for grades 2 and 5 was collected from achievement monitoring and domain referenced tests, teacher logs, and classroom observations. This report focuses on the procedures used in aggregating the reading skills and mathematics content areas. Data were grouped for analysis at three progressively more specific levels: content area; general objective; and specific objective. The content areas for reading skills were Word Attack, Comprehension, and Study Skills. The math skills content areas were Place Value and Numeration, Operations Fractions, Decimal Fractions, Measurement, and Problem Solving. Appendix A contains a listing of the reading skills and math content codes in the aggregated form. Each aggregated case contains 12 digits arranged in four three-digit fields. The fields represent the three grouping levels, and WDRSD or DMP skill and skill level. (BS)