Over the last 10 years, declining school enrollments resulted in nearly 30,000 school closures nationwide. Little research has been done, however, on the effects of closing a high school. This report interprets data gathered both before and after the closing of Wheaton Warrenville High School in a large Chicago suburban school district to determine the impact of the school closure on (1) student achievement, (2) student attitudes, and (3) parent attitudes. Data interpretation shows that the school closure did not have any measurable impact on student grades or achievement as measured by standardized tests, nor did it affect such student personality characteristics as self-confidence, sense of efficacy, and self-concept. Parent attitudes, however, reflected many negative perceptions of the school closure's effect on the school community and on the academic achievement of the students. These negative opinions can be partly attributed to parents' lack of access to factual data, to the degree of controversy reported by the press, and to the perceptions of what they believed to be the community consensus. Appended are 8 references, 28 tables, and 8 figures. (IW)