management). However, this exercise demonstrates the potential of cost‐effectiveness analysis in complementing our analysis to inform policy decisions.

Across all 14 included programs, the average total cost per participant is US$75 (2011, PPP), with the cheapest at US$0.40 (from providing earnings information for school finishers in Madagascar (Nguyen 2008b)) and the most expensive at US$749 (from the minimum‐size conditional cash transfer program in Malawi (Baird, McIntosh, and Özler 2011)) (Table 6).

In Sub‐Saharan Africa, the most cost‐effective program provided households in Madagascar with information on returns to education (Nguyen 2008a). As Table 6 shows, this program increased students’ learning performance by 0.2 SD at a cost of US$0.4 per student. As described in section 4.1, 1 one SD gain in learning is associated with 6.5 years of equivalent schooling (method 2a). Thus, the effect of the Madagascar program translates into 1.5 additional years of schooling for each participant at a total cost of US$0.4 from implementer and beneficiary. In other words, an investment of US$100 can yield 430 additional years of equivalent schooling (if that were possible). Furthermore, considering the long‐term wage income effects described in section 4.2.2, an 0.2 SD improvement in learning by this program can yield an NPV of US$694 from lifetime increased wage income (discounted at 3%), which provides a benefit‐ cost ratio of 1,957, when taking into account the NPV of the program cost (US$0.4). The median cost‐ effective program in Sub‐Saharan Africa took place in Kenya and provided teachers with incentives based on students’ test scores and improved learning by 0.14 SD at a cost of US$4.2 per beneficiary (Duflo, Dupas, and Kremer 2011). For every US$100 invested in this program, it is associated with additional 21.3 years of equivalent schooling and the benefit‐cost ratio reaches 156, when benefits are estimated in terms of life‐time increased earnings. The big returns indicate the high cost‐effectiveness of these interventions that effectively increased learning.

Establishing new schools is considered to be one of the most expensive education investments. However, building these new schools can still be cost‐effective as long as children get sizeable learning gains. In Afghanistan, placing village‐based schooling helped children improve their performance by 0.5 SD at a higher cost of US$111.2 per student enrolled (Burde and Linden 2013). 18.1 additional years of equivalent schooling can be achieved per US$100 and the benefit‐cost ratio is 19 (Table 6). In East Asia, the impact of an school‐based management intervention in Indonesia (Pradhan et al. 2014) that linked school committees to local government translates to 187 additional years of equivalent schooling for every US$100 invested, generating a benefit‐cost ratio of 3,810. Similarly, in India, a remedial education program improved students’ performance by 0.14 SD, which yields a benefit‐cost ratio of 143.

# 5. Discussion

## 5.1 Poverty impacts

A wide range of interventions have increased learning outcomes in low‐ and middle‐income countries. This increased learning can translate into labor market gains, as adults with higher learning scores have higher wages. An 11 percent increase in wages, the projected increase associated with a teacher training program in Uganda, or a 33 percent increase in wages, associated with a reading program in Kenya, mean a sizeable difference for those countries, with roughly one‐third of the population living under the $1.90 per day poverty line (World Bank 2016b).<sup>16</sup> If that one‐third were to have income uniformly distributed

> 16 The last available poverty estimates for Uganda are from 2012 (34.6 percent) and for Kenya are from 2005 (33.6 percent).

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