advantages. First, it allows for cleaner econometric identication and interpretation of the results as our instrument utilizes public school construction guidelines that were applied for GSSs constructed after the 1980s.<sup>9</sup> This also alleviates exclusion restriction concerns that arise if our instrument were to predict other public goods. Second, focusing on the shorter exposure (to GSS) periods is likely to better isolate supply-side eects since GSS construction probably impacts a range of demand factors over a longer time span. It is nevertheless reassuring to note that all of our main results hold in the full sample of villages, both in terms of statistical and economic signicance, and several of these results are in fact stronger (Appendix Table II).<sup>10</sup> Table I presents summary statistics for the nal sample. Two and a half percent, or 232 villages, in this sample received a GSS between 1981 and 2001.<sup>11</sup> Conditional on existence,

> 9We are not aware of similar guidelines used in previous years. To the extent they were, we are reluctant to use the 1981 population (the earliest available census data at the village-level) to construct population rank for earlier years. Focusing on villages which did not receive secondary schools prior to 1981 also allows us to better control for village-level baseline data prior to the construction of a public school. For villages with pre-existing secondary schools, it is harder to discern whether dierences in the baseline data arise from selection into villages or the exposure to the secondary school. While we could have also excluded villages which received girls'/boys' primary schools prior to the 1980s, this is too severe a restriction and would eliminate most of our sample. Finally, we are also concerned with pre-existing secondary schools since we believe they are more likely to reect village wealth, size, or inuence. We therefore also exclude villages whose neighbours' have pre-existing secondary schools, since that could have spillover eects through inter-village marriages and may mask supply-side channels. We are less worried about primary schools in neighboring villages aecting village demand, since there is considerable evidence that younger children do not travel outside their village to go to school (Alderman 1995, Andrabi et al. 2009).

> 10A couple of dierences in the full sample results are worth noting and provide further support for our data restriction. Column (2) of Appendix Table II shows if we use the full sample, the instrument predicts boys' secondary school construction. This is not the case in the restricted sample (Column (5), Table II). The full sample association is not surprising because local rank criteria may have been used for BSS allocation in the past and/or the 1981 population may be an outcome of secondary school construction (since it is no longer a baseline variable as the full sample includes schools constructed before 1981). In addition, the impact of GSS on teacher wages in the village is noteworthy. While our restricted sample result shows that GSS presence leads to a lower wage (Table V), in the full sample we nd that exposure to GSS has a non-linear eect on teacher wages. Initial exposure to GSS is indeed associated with lower wages, but prolonged exposure (more than 26 years) is associated with higher wages (the linear term on years exposure is negative while the quadratic terms is positive and of smaller magnitude). This is indeed consistent with our net supply impact interpretation of a GSS within the time-frame we are in (20 years) but suggests that, in the longer term, the demand eect may dominate: As more and more educated girls become mothers and grand-mothers, they impact educational demand. It therefore oers another important consideration for why restricting our analysis to the reduced sample is appropriate in identifying the (initially dominant) supply channel.

> 11This number is quite low relative to what the school construction guidelines would have suggested. While this is not surprising given that these guidelines were constrained by budgetary limitations, it may lead to concerns about the power of the instrument and the external validity of our results. We therefore address

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