This article estimates peer effects originating from the ability composition of tutorial groups for undergraduate students in economics. We manipulated the composition of groups to achieve a wide range of support, and assigned students—conditional on their prior ability—randomly to these groups. The data support a specification in which the impact of group composition on achievement is captured by the mean and standard deviation of peers’ prior ability, their interaction, and interactions with students’ own prior ability. When we assess the aggregate implications of these peer effects regressions for group assignment, we find that low- and medium-ability students gain on an average 0.19 SD units of achievement by switching from ability mixing to three-way tracking. Their dropout rate is reduced by 12 percentage points (relative to a mean of 0.6). High-ability students are unaffected. Analysis of survey data indicates that in tracked groups, low-ability students have more positive interactions with other students, and are more involved. We find no evidence that teachers adjust their teaching to the composition of groups.

This paper evaluates the effects of two subsidies targeted at schools with large proportions of disadvantaged pupils. The first scheme gives primary schools with at least 70% disadvantaged minority pupils extra funding for personnel. The second scheme gives primary schools with at least 70% pupils from any disadvantaged group extra funding for computers and software. The cutoffs provide a regression discontinuity design that we exploit in a local difference-in-differences framework. For both subsidies we find negative point estimates, which are for some outcomes significantly different from 0. Extra funding for computers and software seems especially detrimental for girls' achievement. The negative effects of extra funding for computers and software are consistent with results from other recent studies casting doubt on the efficacy of computers in schools.

Gender differences in competitiveness have been hypothesized as a potential explanation for gender differences in education and labor market outcomes. We examine the predictive power of a standard laboratory experimental measure of competitiveness for the later important choice of academic track of secondary school students in the Netherlands. Although boys and girls display similar levels of academic ability, boys choose substantially more prestigious academic tracks, where more prestigious tracks are more math- and science-intensive. Our experimental measure shows that boys are also substantially more competitive than girls. We find that competitiveness is strongly positively correlated with choosing more prestigious academic tracks even conditional on academic ability. Most important, we find that the gender difference in competitiveness accounts for a substantial portion (about 20%) of the gender difference in track choice.

This article evaluates the long-term effects of class size in primary school. We use rich data from Sweden and exploit variation in class size created by a maximum class size rule. Smaller classes in the last three years of primary school (age 10 to 13) are beneficial for cognitive and noncognitive ability at age 13, and improve achievement at age 16. Most important, we find that smaller classes have positive effects on completed education, wages, and earnings at age 27 to 42. The estimated wage effect is large enough to pass a cost-benefit test.