The Impact of Schooling Intensity on Student Learning


Duration and intensity of schooling often come up in discussions about educational effectiveness and in education policy debates. Schooling duration, or years of schooling, has previously been linked to greater learning outcomes. Whereas, schooling intensity, or the amount of content covered in a year, is less well understood. Given too much content, students will be overwhelmed, but too little content will result in students being bored. Therefore, more research is needed to better understand how schooling intensity affects student learning.

A new study by by Vincenzo Andrietti and Xuejuan Su in vol. 14, issue 4 helps to bridge this gap.

The Study: 

To examine the effects of schooling intensity on student learning, a new study focused on the G8 Reform in Germany, which compressed schooling duration for academic-track students from 9 to 8 years, while maintaining the same level of academic content and total hours of instruction. This resulted in each year having more hours of instruction and covering more content, a clear increase in intensity level.

Utilizing data on over 30,000 students tested in PISA from 2000 to 2012, the authors take advantage of the staggered implementation of the G8 reform as a quasi-natural policy experiment, and compare learning outcomes before and after the reform across German federal states.


Overall, the reform improved average test scores, but effects differ across subgroups of students. For instance, the reform effect is larger for girls, those with German-born parents, and students with more books at home. However, the difference in the reform effects cannot be readily explained through observed channels. Unobserved factors, such as student preparedness or their capability to cope with the increase in schooling intensity, play an important role. While high-performing students benefit more from the reform, low-performing students hardly benefit at all, resulting in a widening performance gap. Therefore, remedial policy interventions need to focus specifically on struggling students.

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