This study analyzes private tutoring (or extra class) participation and provision in Cambodia using nationally representative data from 138 lower secondary schools. Higher socioeconomic status (SES) students are more likely to have access to fee-based extra classes offered by teachers from their same school and are more likely to enroll when offered. But a substantial number of children with an apparent ability to afford extra classes are not participating, which highlights the role of student engagement in explaining enrichment-driven extra class attendance. Higher capacity and better credentialed teachers are more likely to report providing extra classes, and they also earn more than other teachers engaged in tutoring. As a result, the additional income from extra classes is concentrated in a small subset of teachers. There is some evidence that students who do not participate in extra classes suffer additional negative consequences during regular school hours. These different supply and demand elements are brought together into an analysis of student achievement gaps. Not surprisingly, extra classes are associated with higher test scores on standardized tests in mathematics and physics, but these explain only part of the achievement gap between high- and low-SES students. The largest achievement gaps are instead found between students who do and do not take extra classes, which in turn underscores the importance of shadow education research in Cambodia and beyond.

中文翻译：

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柬埔寨初中教育的影子教育和不平等：了解私人补习参与和提供的动态

本研究使用来自 138 所初中的全国代表性数据分析了柬埔寨的私人补习（或课外辅导）参与和提供。较高社会经济地位 (SES) 的学生更有可能获得同一所学校教师提供的收费额外课程，并且更有可能在提供时注册。但是，大量明显有能力负担额外课程的儿童没有参加，这突出了学生参与在解释充实驱动的额外课程出勤方面的作用。更高的能力和更好的认证教师更有可能提供额外的课程，他们也比其他从事辅导的教师收入更多。因此，额外班级的额外收入集中在一小部分教师身上。有证据表明，不参加额外课程的学生在正常上课时间会遭受额外的负面影响。将这些不同的供需因素结合在一起，对学生成绩差距进行了分析。毫不奇怪，额外的课程与更高的数学和物理标准化考试分数相关，但这只能解释高和低 SES 学生之间的成就差距的一部分。相反，最大的成就差距出现在加课和不加课的学生之间，这反过来又强调了影子教育研究在柬埔寨及其他地区的重要性。将这些不同的供需因素结合在一起，对学生成绩差距进行了分析。毫不奇怪，额外的课程与更高的数学和物理标准化考试成绩相关，但这只能解释高和低 SES 学生之间的成绩差距的一部分。相反，最大的成就差距出现在加课和不加课的学生之间，这反过来又强调了影子教育研究在柬埔寨及其他地区的重要性。将这些不同的供需因素结合在一起，对学生成绩差距进行了分析。毫不奇怪，额外的课程与更高的数学和物理标准化考试分数相关，但这只能解释高和低 SES 学生之间的成就差距的一部分。相反，最大的成就差距出现在加课和不加课的学生之间，这反过来又强调了影子教育研究在柬埔寨及其他地区的重要性。