Just after midnight, the Economic Policy Institute released a relatively short white paper coauthored by ten well-known researchers, Problems with the Use of Student Test Scores To Evaluate Teachers. Key passage from the executive summary:
A review of the technical evidence leads us to conclude that, although standardized test scores of students are one piece of information for school leaders to use to make judgments about teacher effectiveness, such scores should be only a part of an overall comprehensive evaluation. Some states are now considering plans that would give as much as 50% of the weight in teacher evaluation and compensation decisions to scores on existing tests of basic skills in math and reading. Based on the evidence, we consider this unwise. (pp. 1-2)
The strongest passages of the 29-page paper contain the summaries of research on the limits of value-added or growth methods. On first reading, it's a clear explanation of the concerns many people (including I) have with a Procrustean approach to using student test scores for teacher evaluation.