In this paper, we report the results of an innovative systematic review identifying the most effective interventions to improve girls’ access to education and learning outcomes within an evidence base that includes both girl‐targeted and general education interventions. We pose three research questions: (1) Are girl‐targeted interventions more effective for girls’ outcomes than general interventions? (2) For general, non‐targeted interventions, do impacts on girls tend to be larger? and (3) In absolute terms, what are the most effective interventions for girls?

To answer these questions, we collected and reexamined a large database of education studies with access or learning outcomes for students. We categorized the studies as either evaluating girl‐targeted or non‐targeted (i.e., general) interventions and identified all studies that reported gender‐differentiated impacts. Only one in three studies of interventions not targeted to girls report disaggregated impacts by gender, so a first implication of this work is that in order to understand how best to improve girls' education, studies should consistently report impacts for girls. For those studies that did not report gender differentiated impacts, we contacted their authors asking them either to run the additional gender differentiated analysis or to share the data with us. We then standardized the effects of different programs to ensure comparability of effect sizes across studies. Ultimately, we synthesized the effects for girls from 177 studies. (The full list of studies is available in Appendix A.) We find that general, non‐targeted interventions perform similarly to girl‐targeted interventions on average to increase both girls’ access to school and their learning in school. General interventions tend to have similar effects for girls and for boys. (The evidence suggests that if anything, girls benefit more from general interventions, although the differences are not statistically significant.) In examining the most and least effective interventions for girls’ education, we find that girls’ access to school is more responsive to changes in costs, distance, and health conditions; while girls’ learning is more likely to be improved by structured pedagogy and interventions that help teachers to teach at the right level. Later in the paper, we discuss the implications for inequality between boys and girls and cost‐effectiveness of programs.

General, non‐targeted interventions may be more politically palatable for scaling up, and they offer a wider array of evaluated interventions, giving policy makers a richer menu of options among non‐targeted interventions to improve girls’ education. In countries where boys also struggle to achieve quality education, general interventions can simultaneously improve girls’ learning while benefitting boys as well. None of this suggests that programs will not benefit from considering gender issues in their design. Furthermore, many of the interventions included in this review focus on primary education, and as girls reach adolescence, they may face more gender‐ specific constraints. But for achieving access and quality, especially in primary education, specifically targeting girls may not always be necessary to help those girls succeed. If policy makers want to help girls learn, they can make schools better for all children. Furthermore, programs can be mindful of gender issues without being specifically targeted to girls.

# 2. Literature review: The missing evidence

Various researchers have undertaken systematic reviews of evidence on what works to improve girls’ education. For example, Sperling and Winthrop (2015) – building on Herz and Sperling (2004) – summarize eight recent reviews of education impact evaluations and provide a catalogue of 4