Class Size Reduction and Student Achievement: The Potential Tradeoff between Teacher Quality and Class Size
研究加州数十亿美元的班级规模缩小项目对学生成绩的影响，发现缩小班级规模虽提升数学和阅读成绩，但教师经验不足和资质不全削弱了其益处，尤其在贫困和少数族裔学生多的学校。
This paper investigates the effects of California's billion-dollar class-size-reduction program on student achievement. It uses year-to-year differences in class size generated by variation in enrollment and the state's class-size-reduction program to identify both the direct effects of smaller classes and related changes in teacher quality. Although the results show that smaller classes raised mathematics and reading achievement, they also show that the increase in the share of teachers with neither prior experience nor full certification dampened the benefits of smaller classes, particularly in schools with high shares of economically disadvantaged, minority students.