In sum, when looking at all socio-emotional skills taken together, we find that the intervention has significant, positive impacts, for students on average and for different student sub-groups. On average, and across student sub-groups, the teacher-delivered treatment consistently delivers better results. The pattern of impacts on sub-groups is broadly in line with the literature, which documents that students who are at relative disadvantage (i.e. girls and Roma students in our case) benefit relatively more (cf. Sisk et al., 2018).

Roma are a particularly disadvantaged group across the Western Balkans. In North Macedonia, ethnicity, which also determines language and religion, is a socially dividing line and a frequent cause of inter-ethnic conflict, both in the country and across borders with neighboring Albania. Roma (who make up only 3% of the population), are socially and economically marginalized, and subject to discrimination in many areas of life (Robayo-Abril and Millan, 2019; Gatti et al. 2016). Their children typically lag far behind Macedonian and Albanian children in terms of academic achievement. By providing positive role models and using an inclusive language directly aimed at providing counter-stereotypical examples, with a distinct focus on ethnic minorities, our intervention targeted minorities (i.e. Albanian and Roma students) in particular. However, it cannot be ruled out that in the teacher-delivered treatment in which teachers received training on the principles behind the curriculum this has led to a more effective delivery of contents to Roma students. In that sense, our intervention seems to reduce educational inequalities across ethic lines. At the same time, however, our finding that students at the upper end of the pre-treatment S/E skills distribution benefit more than those at the lower end suggests that reducing educational inequalities may be more difficult.

# **5.2 Impacts on GPAs**

# _Short-term GPAs_

Did improvements in middle-school students’ general S/E skills translate into improvements in students ́ academic achievement? Table 4b Panel B shows impacts on short-run GPAs, calculated immediately after the intervention in the fourth quarter across math, English, and first language. Note that the sample size is larger here because GPAs are obtained from official, administrative records and are therefore not subject to missing information.

Overall, we find little evidence of impacts of our intervention on short-term GPAs. If anything, there is an improvement in short-term GPAs of about 2% SD on average, which is only marginally significant at the 10% level in the student self-learning treatment (with a similar point estimate and standard error in the teacher-delivered treatment). Likewise, there is little evidence for differential impacts by student sub-group: impacts are similar between gender, sixth and seventh-grade students, and students in different terciles of the pre-treatment GPA distribution. Interestingly though, we do find a larger impact on Roma students in the teacher-delivered treatment. This is interesting because Roma students are the sub-group of students for whom we find the strongest impacts in terms of our S/E skills index (about 42% SD, cf. Table 4b Panel A). There is thus consistency between the finding for our S/E Skills index and the finding for GPAs of Roma students. The effect size for GPAs, however, is rather small, at about 6% SD.

Our estimates on GPAs are likely downward biased, for several reasons: first, as noted previously, there could be a lag between students taking exams or tests and teachers reporting their results. Although teachers are encouraged to report results to official records within two weeks after taking the assessment, we cannot exclude the case that some results from tests taken during the pre-treatment period (i.e. before the intervention had finished or even started) are reported only during the post-treatment period, deflating post-treatment GPAs and resulting in lower-bound estimates. Second, there is the possibility that teachers engage in “grading on a curve”. Although this is not common practice in North Macedonia, we cannot exclude the case that single teachers do behave that way. Again, this kind of behavior would bias our estimates downwards, which, as in the previous case, works in our favor. Third, impacts on GPAs may need some time to materialize. We look at this next.

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