By Andrew Flowers
Is evaluating teachers an exact science? Many people — including many teachers and their unions — believe current methods are often too subjective and open to abuse and misinterpretation. But new tools for measuring teacher effectiveness have become more sophisticated in recent years, and several large-scale studies in New York, Los Angeles and North Carolina have given those tools more credibility. A new study released on Monday furthers their legitimacy; and as the science of grading teachers advances, it could push for further adoption of these tools.