We partnered with the Ghanaian government to test simultaneously four methods of increasing achievement—assistant-led remedial pull-out lessons, remedial after school lessons, or smaller class sizes or teacher implemented partial day tracking—in schools with low and heterogeneous student achievement. The interventions increased student learning by about 0.1SD, rising to 0.4SD when adjusting for imperfect implementation, with no effects on attendance, grade repetition, or drop-out. Test score increases were larger for girls. Test score gains persisted after the program ended. Assistants implemented the program with higher fidelity than teachers, although their fidelity decreased over time while teacher fidelity marginally improved.

中文翻译：

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大规模增加学习的四项政策的实验证据

我们与加纳政府合作，在学生成绩较低且存在差异的学校中同时测试四种提高成绩的方法：助理主导的补习课、课后补习课、较小的班级规模或教师实施部分日间跟踪。这些干预措施使学生的学习成绩提高了约 0.1SD，根据不完善的实施情况进行调整后，学生的学习成绩提高到 0.4SD，并且对出勤率、留级率或退学率没有影响。女孩的考试成绩增幅更大。项目结束后，测试成绩仍然持续上升。助理以比教师更高的保真度实施该计划，尽管他们的保真度随着时间的推移而下降，而教师的保真度略有提高。