Why is value-added assessment a good tool for gauging achievement?
Reports of average test scores reflect the performance level of students, not the effectiveness of a school in bringing about those performance levels. School effectiveness is reflected in annual student achievement increases, and the great virtue of value-added assessment is that it accurately reports achievement gains regardless of students’ beginning test scores or social, economic, ethnic, or other background differences. By statistically leveling the playing field, it permits users to compare the achievement gains produced by different teachers, schools, and school systems regardless of the advantages or disadvantages had by their students.
