Throughout this article, we have argued that when classrooms are gender integrated and gender inclusive, there are positive social and academic outcomes for students, teachers, and the classroom/school climate as a whole. Our focus on gender reflects the fact that gender is one of the first and strongest ways in which children and youth (and adults) organize their social interactions and relationships. By some estimates, gender accounts for 70% to 80% of the variance in students’ choices of peer partners (Fabes, Martin, & Hanish, 2003; Martin & Fabes, 2001). Over time, this gender segregation may contribute to the emergence of more serious interactional problems, such as gender-based bias, harassment, and bullying and the development of harmful stereotypes about girls’ and boys’ academic abilities and interests, which can hinder academic success (Fabes et al., 2013; Hunt & Gonsalkorale, 2014). Moreover, Maccoby (1998) argued that the roots of difficulties in adult male–female relationships evolve out of the gender-segregated nature children’s peer preferences. 
Whereas exclusion from other-gender interactions can potentially be deleterious, inclusion with other-gender peers can potentially be beneficial. Playing with other-gender peers provides increased exposure to gender neutral and cross-gender activities, thereby expanding children’s opportunities to learn new skills (Fabes, Martin, & Hanish, 2003). Mixed-gender interactions have been found to be related to lower rates of aggression and peer victimization, as well as increased levels of prosocial interactions (e.g., Faris & Felmee, 2011; Xiao, Alexander, & Fabes, 2018). Children with other-gender friends tend to be more sociable and are more likely to exhibit positive affect in the classroom than those without other-gender friends (Howes, 1988) and have more positive and less negative attitudes toward the other gender (Halim et al., 2019). Feeling included by and efficacious in interactions with other-gender peers has been found to be positively related to classroom climate (Zosuls et al., 2014).
Despite the relative ubiquity of gender segregation, there is evidence that the gender-segregation cycle can be affected and that the gender-integration cycle can be effectively promoted. The development of Buddy-Up and Meet-Up was based on the application of the intergroup contact and peer exposure theories, and the Buddy-Up and Meet-Up strategies have shown promising outcomes for individual students, for the quality of relationships in classrooms, and for the overall classroom climates. Strategies such as these that that allow boys and girl to feel socially connected are crucial to children’s success (Baumeister & Leary, 1995).
Although schools and educators are tasked with the creation of socially harmonious school/classroom environments that promote positive academic, social, and emotional outcomes., this is not a simple feat. For example, addressing the gendered nature of students’ peer relationships at school is complicated, involving structuring and supporting the peer interactions that occur in dyads and small and large groups as well as teaching the social, emotional, and relational skills needed to interact competently. Educators face stress from those stakeholders who are outside of the school, in the form of pressure and demands from parents and policymakers, and often these demands are for a more rigorous academic (and not social) focus in the classroom. In addition, despite teachers and parents recognizing the importance of helping children develop healthy, lifelong relationships skills, there is a lack of recognition of issues related to peer segregation (especially for gender) and a lack of understanding of the best practices that promote harmony in schools. Rather than being a distinct or separate part of the classroom experience, the relational tone of the classroom has a strong and direct impact on teachers’ ability to focus attention on academic activities, on children’s ability to collaborate and participate in learning tasks, and on their achievement outcomes. This underscores the need to create classroom and school climates, policies, and structures that support peer relationships and socioemotional learning (Hanish et al., 2016; Juvonen, 2018).
Although our focus on gender integration reflects our study of boys and girls, as previously noted, we acknowledge that gender is not binary and that for classrooms and schools to be truly gender integrated and inclusive, they must support students across the gender spectrum. Thus, efforts related to gender integration in schools must also address ways to help LGBTQ students feel safe, secure, and connected. Evidence suggests that quality of peer relationships play an important role in facilitating inclusion for sexual-minority students. For example, studies show strong associations between gay–straight alliances (that are typically youth led) and the well-being and safety of sexual-minority students (Ioverno, Belser, Baiocco, Grossman, & Russell, 2016; Poteat, Yoshikawa, Calzo, Russell, & Horn, 2017).
We believe that the strategies and ideas presented in this article for promoting gender integration/inclusion would apply for LGBTQ students. For example, teachers could bring students who do and those who do not identify themselves as LGBTQ together in cooperative academic activities as a way to reduce outgroup bias and prejudice. Although the research on intergroup contact and attitudes/behaviors toward LGBTQ peers in youth is sparse, the adult literature does provide some support for the conclusion that knowing a gay or lesbian person leads to improved attitudes and reduced prejudice toward gay and lesbian people (Herek & Capitanio, 1996). Heinze and Horn (2009) examined this question in adolescents and found that adolescents who had a lesbian or gay friend were relatively less likely to judge homosexuality as wrong, were comfortable interacting with lesbian or gay peers, and were likely to evaluate exclusion and teasing a lesbian or peer as wrong. However, adolescents reporting casual contact did not report more favorable attitudes than those students reporting no contact, and in some cases reported more prejudicial attitudes. It may be that the quality of contact or relationship moderated these patterns.
Such findings support the notion that contact in and of itself (as previously noted) is not enough to improve intergroup attitudes and decrease LGBTQ prejudice during this developmental period. Heinze and Horn noted that, because of the increased salience of sexuality and sexual identity in adolescence, and the fact that homosexuality is a highly stigmatized identity, the type of intergroup contact is particularly important during this developmental period. Such findings underscore the research suggesting that simply putting people together under nonoptimal contact situations may produce effects that are detrimental to goals of improving intergroup relations. However, bringing LGBTQ students together with non-LGBTQ students can have positive effects on classroom and school climates if adults do this in a way that provides students opportunities to interact in positive, meaningful, and rewarding ways (Heinze & Horn, 2009).
Finally, it is important to note that society is becoming increasingly diverse and interconnected. Despite this, many students who do not fit the stereotypic majority norm are still made to feel that they are not accepted; do not feel safe or efficacious; and are left out, excluded, and harassed. Helping all students feel included is a challenge that has to be undertaken by our schools (Juvonen, 2018). But diversity in and of itself does not guarantee inclusion. For example, as we have discussed here, although most U.S. schools and classes are coeducational and are thus gender diverse in terms of having both boys and girls in them, this does not guarantee that they are gender inclusive. Similarly, for all forms of diversity—race/ethnicity, language, immigration status, sexuality, gender expression, ability levels, and so on—having diversity within the classroom is not necessarily going to mean that students feel included and safe and benefit from the diversity. Furthermore, the adults in children’s lives have different experiences with peer diversity than do the children and youth of today. As Fabes and colleagues (Fabes et al., 2018) noted, many of the adults who parent, mentor, teach, and advise children and youth today did not grow up in a peer context that is as an openly diverse as it is now. Moreover, many majoritized adults have not experienced the discrimination and prejudice that minoritized children and youth have. Thus, many of these caring adults, although well intended, are often not equipped with the knowledge and skills to help minoritized children and youth (and majoritized children and youth as well) navigate diverse but often challenging environments. For these reasons, it is all the more urgent to conduct research and develop effective strategies that can be used by caring adults as they build more inclusive educational environments, practices, and policies for today’s children and youth.
