(2015); Bursztyn et al. (2017, 2019)) and in politics (e.g. Perez-Truglia (2018)). Similarly, Akerlof and Kranton (2000, 2002, 2010) translated theories of social identity into an economics framework to propose that social identity influences economic outcomes when deviating from the prescribed behavior is inherently costly. When individuals derive utility from fitting in with society or with their peers, there may be a social cost of rebelling against prevailing norms. Adolescence, in particular, is a period when the desire to conform to be popular or fit in with peers may be felt acutely.<sup>3</sup> For example, Bursztyn and Jensen (2015) and Bursztyn et al. (2019) show that US students in high school under-invest in education to signal social compatibility to their peers. Similarly, Austen-Smith and Fryer (2005) show that minority US students shy away from educational investments to avoid “acting white” and in this way improve their social standing with peers. When opinions are observable to others, adolescents may try to conform to the group responses due to peer pressure.<sup>4</sup> Our experimental findings have potential implications for understanding different types of normative social influence more generally.

In this paper, we use random variation in individual participation in a program delivered to young adolescents that was designed to challenge restrictive gender norms in Somalia. Early adolescence is viewed as a critical window of opportunity for formulating positive gender attitudes and behaviors as children transition into adulthood (Baird et al., 2019). The gender norms training program called _Choices_ is implemented by the NGO Save the Children and targets adolescents aged 10-14 years.<sup>5</sup> This is the first randomized controlled trial (RCT) experiment to examine the _Choices_ program’s impact.<sup>6</sup> We report results from both individual-level surveys and a lab-in-the-field experiment to estimate the impact of the _Choices_ program on adolescents’ gender attitudes and behaviors, and examine whether the effects differ for boys and girls. In the randomized experiment we also test whether the participation of their parents in a complementary gender norms program influences the effects of the _Choices_ program on adolescent outcomes.<sup>7</sup> Importantly, we measure persistence of program effects beyond an immediate effect using two follow-up survey rounds: 6 months and 2 years post-intervention. We test a number of key mechanisms examining whether the program affects personally held gender attitudes, perceptions of others’ beliefs, the propensity to conform to gender norms, and the willingness to stand up for their own beliefs, even in the face of opposing views.

First, our results show that the _Choices_ program in Somalia has a positive treatment impact on the personal gender equitable attitudes reported by both adolescent boys and girls. The treatment led to a 0.07 standard deviation increase in an index of gender equitable attitudes in the short-run, and a 0.05 standard deviation unit increase in the longer-run.

> 3The _Choices_ program studied here targets young adolescents aged 10-14. Therefore, study participants may be vulnerable to peer pressure to conform. One may also expect adolescence to be a period of greater rebellion against societal expectations as individuals wrestle with gaining a sense of individuality and identity.

> 4We examine conformity as a behavioral outcome that measures an adolescent’s likelihood of changing their privately-held personal attitudes when grouped with peers of the same or opposite sex in public.

> 5 _Choices_ is a component of the Challenging Harmful Attitudes and Norms for Gender Equality and Empowerment in Somalia (CHANGES) program under the Social Norms and Participation (SNaP) project.

> 6The _Choices_ program has been adapted for use in over 10 countries. The program was evaluated in Nepal using quasi-experimental evaluation methods by Lundgren et al. (2013, 2020).

> 7Parents are invited to attend separate training sessions in an “Engaging Men and Boys” (EMB) component of the CHANGES program attended by adults in the community.

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