This study evaluates the effectiveness of a wise Intervention to reduce aggressive behaviors and promote prosocial behaviors toward LGB-TNB individuals among Spanish adolescents. Half of the participants will receive the experimental intervention, while the other half will receive a control intervention.

Discrimination based on sexual orientation and gender identity is a social problem of great relevance. Sexual orientation is understood as the mechanism that directs affective-sexual attraction and interest, manifesting with varying intensity. Regarding gender identity, it has historically been interpreted under a binary paradigm based on external sexual organs, rendering trans and non-binary identities invisible. However, it is currently understood as the internal feeling about one's own gender, so that trans and/or non-binary people represent those whose gender identity differs from the one assigned at birth.

Despite the growing visibility, public awareness, and recognition of the rights of lesbian, gay, bisexual, trans, and non-binary people (LGB-TNB), discrimination based on sexual orientation and gender identity continues to be a social problem of great relevance with serious consequences for those who suffer it. This reality underlines the need to implement effective interventions aimed at addressing these aggressive behaviors and the mechanisms that sustain them, not only among those who perpetrate acts of violence, but also among people who witness these aggressive behaviors.

In addition, intervening during adolescence is especially relevant, as this stage represents a critical moment in the moral, social, and emotional development of individuals. Moreover, during adolescence, discriminatory behaviors and peer aggression increase, and previous studies show that LGB-TNB people face a higher risk of violence in educational settings. Nevertheless, although adolescence becomes a critical period for the development of risk behaviors, it also involves important transitions and learning opportunities. Furthermore, adolescence is a turning point during which well-designed interventions have a high potential to redirect a person's developmental trajectory in a lasting way. Therefore, it can be an especially favorable moment for implementing interventions.

In this way, numerous interventions have been carried out in educational settings to prevent aggressive behaviors among peers. Although most of these initiatives have mainly focused on more general problems, such as bullying and cyberbullying, in recent years preventive interventions specifically aimed at reducing aggressive behaviors based on sexual orientation and gender identity in both face-to-face and digital contexts have increased. However, most current interventions focus on educating people about issues related to LGB-TNB topics, reaching mixed and contradictory results regarding their effectiveness, and also highlighting that there is little empirical evidence about the robustness of the effects of LGB-TNB interventions and their underlying mechanisms. Therefore, these interventions present areas for improvement that constitute important challenges for scientific psychology.

Recently, interest has grown in social psychology regarding a new approach to interventions, which have been called wise interventions. Many of these interventions have impactful results because they are usually very brief in time and produce lasting changes in people's behavior. Moreover, this type of intervention is of great interest in adolescence, as they allow themselves to be designed in such a way that they are perceived as respectful of students' autonomy and status, so that they feel they are making their own decisions.

Therefore, the aim of this project is to adapt to the LGB-TNB context a wise intervention to reduce online and offline aggression among adolescents, especially based on sexual orientation and gender identity, and to increase the intention to support and prosocial behaviors when participants witness these aggressions, especially those directed at LGB-TNB people.

Inclusion Criteria:

• Informed consent by the adolescents and their families.
• To be fluent in Spanish and/or Euskera.

Exclusion Criteria:

• Lack of permission by families and the adolescent.
• Lack of understanding of the instructions.

Raw data will be available at OSF when the results of the study are published.

The study protocol and informed consent protocol will be published at clinicaltrials.org. Data will be available at OSF when the results are published.

Public

Allocation will be concealed to the participants and teachers. Assessment will be done online through self-reports.