Designed as an overview of the 1979 and 1980 Illinois Inventory of Educational Progress (IIEP) in fourth, eighth, and eleventh grade reading, this report presents the results for each grade level along with performance comparisons between years and topic areas (using sources of information and reading in the social sciences, literature, and the sciences). Section one of the report discusses the purpose and rationale of the assessment and briefly summarizes the findings. Section two, the bulk of the report, contains an analysis of each of the test items in the assessment at all three grade levels, followed by a summary of the overall observations of the reading panel interpreting the assessment. Section three offers general observations and future considerations gleaned from the results of the assessment. Appendixes contain six tables displaying teacher opinions related to the test items (degree of exposure in class, importance of mastery, and degree of difficulty) and a sample of the teacher survey form. (RL)