Are we measuring achievement gains accurately enough?
Will value-added analysis make performance-based evaluations a viable tool for school improvement?
Family background decisively shapes student achievement. As a result, simplistic accountability systems that dole out rewards or sanctions based on test scores run the risk of punishing schools and teachers for problems beyond their control.
The Solution, Perhaps
Attempt to measure the achievement gains that a school or teacher elicits by subtracting their latest test scores from the previous year’s. These gains are less susceptible to the home influences than the simple level of achievement at one point in time. Thus, by measuring gains, we can pinpoint the “value” that a school has “added” to its students’ educational experience.
Value-added analysis, while a promising innovation, suffers from various statistical shortcomings. Errors in measurement could lead to schools’ and teachers’ being rewarded or sanctioned wrongfully. The question is whether the benefits of value-added analysis outweigh the flaws.