This third annual report on student achievement in Illinois continues the State Board of Education practice of providing a synthesis of a variety of achievement measures. Test results used for this report come from: (1) Illinois Inventory of Educational Progress (IIEP); (2) Scholastic Aptitude Test (SAT); (3) National Assessment of Educational Progress; (4) American College Test; (5) Decade Study Test; and (6) Second International Mathematics Study. Data collected regarding student performance in mathematics showed that although the achievement of Illinois students is at the national average, the nation as a whole compares unfavorably with other countries. Science scores for Illinois students were at the national average, and the IIEP (used only in Illinois) showed improvement in grades four, eight, and eleven. Reading achievement scores indicated that no great movement took place, although fourth, eighth and eleventh grades showed a slight drop. Across all curricular areas was the concern that students were not performing well on test items requiring higher order thinking skills (analysis, synthesis, evaluation, and problem-solving). Student factors most important in explaining performance levels were student expectations/standards of performance, number of relevant courses taken, and parental influences. School size was the strongest single influence among school factors and performance was higher in high schools with more than 215 students. The report provides support for at least four major reforms: (1) establishment of learner outcomes at the state and local levels; (2) need for a statewide assessment process; (3) reorganization and/or consolidation of small high schools; and (4) state initiative for early childhood education to increase levels of achievement. A brief list of references and related readings is included. (LMO)