END THE TESTS, END THE ACCOUNTABILITY:

[O]ur results confirm that using average test scores from a single year to judge school quality is unacceptable from a fairness and equity perspective. Using demographic adjustments is an unsatisfying alternative for at least two reasons. In addition to providing less accurate information about the causal impact of schools on their students' learning, the demographic adjustments implicitly set lower expectations for some groups of students than for others.

Some civil rights advocates have voiced similar concerns about accountability systems that rely exclusively on growth measures, which could allow schools serving disadvantaged students to avoid sanction even if their students' academic progress is insufficient to close achievement gaps. This is a legitimate concern, and policymakers may want to strike a balance between average scores and growth when deciding where to focus improvement efforts. However, not administering the annual tests required to produce student growth measures would make it impossible to distinguish those schools where students learn very little from those that perform well despite difficult circumstances.

An exclusive reliance on student performance levels, on the other hand, is perhaps the principal shortcoming of the much-maligned accountability system mandated by No Child Left Behind. Under that system, whether a school makes Adequate Yearly Progress is determined primarily based on the share of students scoring at proficient levels in math and reading in a given year. But a key reason Congress mandated such a system in 2002 was that many states were not yet administering annual tests, and many of those that did lacked the capacity to track the performance of individual students over time. Eliminating the annual testing requirement would therefore recreate the conditions that led to the adoption of a mistaken accountability system in the first place.

Policymakers thus face a stark choice: require annual testing or settle for low-quality and potentially misleading information on school quality.

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