The Causal Effects of an Intensified Curriculum on Cognitive Skills: Evidence from a Natural Experiment

Abstract

This paper exploits a unique universal educational policy -implemented in most German states between 2001 and 2008 -that compressed the academic-track high school curriculum into a (oneyear) shorter time span, thereby increasing time of instruction and share of curriculum taught per grade. Using 2000-2012 PISA data and a quasi-experimental approach, I estimate the impacts of this intensified curriculum on cognitive skills. I find robust evidence that the reform improved, on average, the reading, mathematical, and scientific literacy skills acquired by academic-track ninthgraders upon treatment. However, I also provide evidence that the reform widened the gap in student performance with respect to parental migration background and student ability. Finally, although the reform did not affect, on average, high school grade retention, I find that the latter increased for students with parental migration background. Taken together, these findings suggest that moving to a compressed high-school curriculum did not compromise and benefited, on average, students' cognitive skills. However, they also raise equity concerns that policy-makers should be aware of.

Inequality of Educational Opportunities and the Role of Learning Intensity: Evidence from a Quasi-Experiment in Germany

“…However, given the broad definition of learning intensity this may still be compatible with findings that the G-8 reform itself had small positive effects on mathematics/science test scores in contrast to reading test scores (Camarero Garcia, 2012;Andrietti, 2016;Büttner & Thomsen, 2015). Furthermore, Dahmann (2017) shows that cognitive skills measured by IQ proxies did not causally change due to the reform, but only gender-specific differences may be reinforced.…”

“…Nevertheless, Andrietti (2016) or 14 Some background information on the OECD's PISA data, its advantages and disadvantages to measure educational outcomes as well as on the representativeness of these data across states and over time is provided in Appendix A.2.1.…”

“…Despite the resulting public controversy that has even led some federal states to reverse it, only a few studies have evaluated the G-8 reform and its effects on educational outcomes (e.g. Büttner and Thomsen (2015); Andrietti (2016); Huebener, Kuger, and Marcus (2017)). Those studies tend to find non-significant positive effects of the reform on a student's average cognitive skills and educational outcomes, such as final marks for the university access diploma.…”

Can Raising Instructional Time Crowd Out Student Pro-Social Behaviour? Evidence from Germany

“…Raising instructional time -the allocated number of hours per year that students spend in formal classroom settings -is often found to have positive effects on cognitive skills such as maths and language ability (Bellei, 2009;Cortes and Goodman, 2014;Taylor, 2014), as well as standardised maths, reading, and scientific literacy test scores (Andrietti, 2016;Cattaneo et al, 2016;Huebener et al, 2017). 1 Differences in instructional time between countries are also found to account for some of the observed international gaps in student achievement (Lavy, 2015;.…”

“…6 Next to this literature in economics stands a large body of literature in political science on the relationship 4 to the literature on instructional time (Bellei, 2009;Cortes and Goodman, 2014;Cortes et al, 2015;Herrmann and Rockoff, 2012;Taylor, 2014), and in particular, to the stream that exploits the "G8" reform as a source of exogenous variation: since the first data became available, the reform has been used -due to its features -as a laboratory for empirical research in educational economics. The more sophisticated studies use difference-in-differences designs that exploit variation in its implementation across federal states and school cohorts; they examine its effects on graduation age, grade repetition, and graduation rates (Huebener and Marcus, 2015), postsecondary educational choices , performance (Andrietti, 2016;Homuth, 2012;Huebener et al, 2017), health (Quis and Reif, 2017), and well-being (Quis, 2015). 7 Here, the studies that are methodologically most closely related to ours are Dahmann and Anger (2014) and Dahmann (2017): we use the same dataset and a similar specification as these authors, who show that the reform affects personality traits, and to some extent, cognitive skills.…”