Educational interventions are often evaluated and compared on the basis of their impacts on test scores. Decades of research have produced two empirical regularities: interventions in later grades tend to have smaller effects than the same interventions in earlier grades, and the test score...

Educational interventions are often evaluated and compared on the basis of their impacts on test scores. Decades of research have produced two empirical regularities: interventions in later grades tend to have smaller effects than the same interventions in earlier grades, and the test score...

Teachers often deliver the same lesson multiple times in one day. In contrast to year-to-year teaching experience, it is unclear how this teaching repetition affects student outcomes. We examine the effects of teaching repetition in a setting where students are randomly assigned to a university...

Mixed-aged classes (MA-classes) are a common phenomenon around the world. In Sweden, these types of classes increased rapidly during the 1980:s and 1990:s. But the scientific evidence of the benefits of MA-classes is not convincing. In this paper, we estimate the effect of attending an MA-class...

In this paper, we estimate the effect of pupil's relative age within the first grade of primary school on math and reading test scores at age 15. The main objective is to evaluate the long-term causal effect of relative age in the first grades of primary school on pupil's test in 16 different...

"There is substantial cross-country variation in secondary school design, with some countries tracking students into different ability schools very early, and other countries with little or no tracking at all. Does tracking length affects school performance, as measured by standardized test...