electroencephalograms within a lab-in-the-field setting.<sup>10</sup> We find that this low-intensity intervention works in the context of a developing and highly violent country, and that its short-term effects are similar in magnitudes and signs to those of middle-intensity interventions in the United States. (Durlak et al., 2010; Cook et al., 2010). For example, our estimations indicate that students assigned to treatment have better attitudes toward school and reduce absenteeism by 23%. Moreover, we find a reduction in violence and misbehavior at school in both student and teacher reports.

In line with the evidence that emotional and behavioral—that is, noncognitive—skills promote and indirectly influence cognitive development (Cook et al., 2011; Cunha and Heckman, 2008), we also find the ASP successfully increases participant academic achievement. On average, after seven months of intervention, grades are 0.11–0.13 standard deviations higher for treated students. The intervention also reduces the probability of course repetition by 2.8 percentage points.

Overall, these effects are consistent with the expected results from learning and protection services that the ASP can deliver. Specifically, these interventions can provide an innovative learning structure for students, affecting their disposition toward school and learning. Additionally, these programs can promote skills such as resilience and control over automatic responses and bad behavior. Finally, the ASP can provide protection from unsafe neighborhoods by reducing the time children and adolescents may spend with delinquent peers. Unfortunately, the experimental design does not allow us to disentangle these mechanisms, so we can only provide suggestive evidence that the learning channel is likely driving all the effects.

Differences in ASP effects by students’ initial propensity for violence show the program benefits both high- and low-violence children but in different categories of outcomes. Highly violent children are driving the effects on academic performance and less violent students are performing better with regard to misbehavior at school and attitudes toward school and learning. We argue that automatic responses that generate bad behavior may be harder to modify, especially for those accustomed to acting that way or whose individual and family characteristics limit their improvement. In other words, a highly violent child may find it easier to attend school more regularly than to stop hitting classmates.

We then study spillover effects in this context. Our estimations indicate the ASP also has indirect short-term effects on nonenrolled children. Exploiting the exogenous percentage of treated students within each classroom, we find positive spillover effects from the exposure of nonenrolled students to a higher proportion of treated classmates on both academic and violence outcomes. The magnitudes of these effects are 0.08–0.09 standard deviations on academic performance and

> 10The EEG devices and the experimental paradigm were piloted before going to the field in a lab setting at the Laboratory for Intelligent Imaging and Neural Computing (LIINC) at Columbia University (Egana-delSol, 2016b).

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