We examine the dynamic nature of teacher skill development using panel data on principals’ subjective performance ratings of teachers. Past research on teacher productivity improvement has focused primarily on one important but narrow measure of performance: teachers’ value‐added to student achievement on standardized tests. Unlike value‐added, subjective performance ratings provide detailed information about specific skill dimensions and are available for teachers in non‐tested grades and subjects. Using a within‐teacher returns‐to‐experience framework, we find, on average, large and rapid improvements in teachers’ instructional practices throughout their first 10 years on the job as well as substantial differences in improvement rates across individual teachers. We also document that subjective performance ratings contain important information about teacher effectiveness. In the district we study, principals appear to differentiate teacher performance throughout the full distribution instead of just in the tails. Furthermore, prior performance ratings and gains in these ratings provide additional information about teachers’ ability to improve test scores that is not captured by prior value‐added scores. Taken together, our study provides new insights on teacher performance improvement and variation in teacher development across instructional skills and individual teachers.

中文翻译：

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教师技能发展：来自校长表现评级的证据

我们使用校长对教师主观绩效评级的面板数据来检验教师技能发展的动态性质。过去关于教师生产力提高的研究主要集中在一个重要但狭隘的绩效衡量标准上：教师对学生在标准化考试中取得的成就的附加值。与增值不同，主观表现评分提供了有关特定技能维度的详细信息，可供未考试年级和科目的教师使用。使用教师内部经验回报框架，我们发现，平均而言，教师在工作的前 10 年中的教学实践取得了巨大而快速的改进，并且各个教师之间的改进率存在显着差异。我们还记录了主观绩效评级包含有关教师效率的重要信息。在我们研究的地区，校长似乎在整个分布中区分教师的表现，而不仅仅是在尾部。此外，先前的表现评级和这些评级中的收益提供了关于教师提高考试分数的能力的额外信息，而这些信息是先前增值分数所没有的。总之，我们的研究提供了关于教师绩效改进和教师发展在教学技能和个别教师方面的变化的新见解。先前的表现评分和这些评分中的增益提供了关于教师提高考试成绩的能力的额外信息，而这些信息是先前增值分数所没有的。总之，我们的研究提供了关于教师绩效改进和教师发展在教学技能和个别教师方面的变化的新见解。先前的表现评分和这些评分中的增益提供了关于教师提高考试成绩的能力的额外信息，而这些信息是先前增值分数所没有的。总之，我们的研究提供了关于教师绩效改进和教师发展在教学技能和个别教师方面的变化的新见解。