Keywords

The negative consequences of prejudicial attitudes and behavior on child development are extensive (Killen, Rutland, & Ruck, 2011). Children who experience unfair treatment, exclusion, discrimination, and victimization are at risk for negative developmental outcomes, including social withdrawal, depression, anxiety, and a lack of motivation to succeed in school (Marks, Seaboyer, & Garcia-Coll, 2015; Rivas-Drake, et al., 2014). Overall, prejudicial attitudes are pervasive throughout most cultures and societies and have been theorized to reflect social group norms that perpetuate status hierarchies and enable high-status groups to maintain the status quo (Gaertner & Dovidio, 2005; Simpson & Dovidio, 2014). Prejudicial attitudes and behavior create negative environments for both children and adults. However, because stereotypes and biases are deeply entrenched by adulthood, the window of opportunity for intervention is in childhood. Without a doubt, addressing, reducing, and diminishing prejudicial attitudes are both urgent and necessary for fostering a healthy and productive society.

Developmental research on the origins of prejudice has moved from a top-down socialization perspective to an interactive, constructivist framework. Adults are not the only agents that perpetuate social hierarchies and convey prejudicial messages to children. Investigations of children’s worlds also reveal child-instigated social inequalities, existing along with hierarchies in the adult world, sometimes mirroring adult forms of bias and sometimes reflecting hierarchies unique to childhood (Brown, 2017; Levy, Lytle, Shin, & Hughes, 2016). Inequity and unfair treatment of others begin early in development, and in some contexts, children reinforce prejudicial attitudes to maintain group identity. Children are both the perpetrators and the victims of prejudicial attitudes about others. Thus, current research examines both exogenous factors that contribute to experiences of prejudice in childhood (socioeconomic, cultural, and adult-imposed inequalities) and endogenous factors that stem from within the child (biological, social-cognitive, and social-emotional factors that contribute to children’s social hierarchies and intergroup relationships and attitudes).

Prejudice emerges early in childhood and takes many forms, from implicit biases to explicit negative judgments. Research has shown that implicit biases take different forms in childhood. While many implicit biases are automatic, uncontrolled negative associations, many explicit biases reflect underlying judgments that the beholders are aware of but have not realized that these forms of judgments result in prejudice (Baron, 2015; Baron & Banaji, 2006; Rutland, Cameron, Milne, & McGeorge, 2005). Explicit biases encompass more overt assignments of traits, intentions, and abilities about individuals based solely on group membership and are those that individuals are aware that they hold (McGlothlin & Killen, 2010; Nesdale, Maass, Durkin, & Griffiths, 2005). The distinctions between implicit and explicit forms of bias are not dichotomous, however, nor mutually exclusive (Killen, Mulvey & Hitti, 2013). Many explicit judgments are not always deliberately prejudicial but made in the context of preserving group functioning and group identity. The full continuum of prejudice in childhood, from implicit to explicit, thus warrants close examination.

Theoretical Framework

In this chapter, we review research on prejudice in childhood from an intergroup social developmental perspective, one that seeks to understand how prejudice emerges and examines the development of group-level biases and stereotypes in childhood. We draw on the social reasoning developmental model to investigate children’s psychological, moral, and societal (group) explanations regarding intergroup social encounters as well as the factors that hinder and promote prejudice in childhood (Killen, Elenbaas, & Rutland, 2016; Rutland & Killen, 2017). The social reasoning developmental model provides a framework for investigating when individuals use moral, psychological, and societal (group functioning and group identity) judgments to reject social exclusion as well as when these forms of reasoning perpetuate negative attitudes toward others. The theory draws from social domain theory (Smetana, Jambon, & Ball, 2014; Turiel, 2002) for capturing different types of justifications used to reject or support exclusionary and discriminatory behavior, as well as developmental social identity theory (Abrams, Rutland, Pelletier, & Ferrell, 2009; Nesdale, 2008) to analyze intergroup dynamics to determine the role that group identity plays in this process. Group identity can foster ingroup bias, but knowledge of how groups work can also enable individuals to view social inequalities between groups as wrong and unfair.

We report on empirical research, which has demonstrated how morality, group identity, and psychological knowledge bear on the acceptance or rejection of prejudicial attitudes. First, we delineate research on intergroup social inclusion and exclusion, including both minority and majority perspectives. Second, we discuss the role of intergroup contact and social experience for reducing prejudice, particularly how cross-group friendships decrease prejudice and bias. Third, we describe new findings, which connect children’s and adolescents’ mental state knowledge about others (others’ beliefs, desires, and intentions) with their ability to reject or condone stereotypic expectations and different forms of bias. Fourth, we describe research on when children challenge prejudicial and unfair treatment of others. Specifically, we identify how children consider group membership when evaluating and rectifying social inequalities, when they reject bullying behavior and unfair norms and when taking another’s perspective reduces prejudice. Finally, we outline recommendations for interventions to reduce prejudice in childhood.

Intergroup Peer Inclusion and Exclusion

Children perceive and make judgments about groups based on many characteristics. Research has shown that intergroup categories such as gender, race, wealth, and ethnicity are highly salient markers that children consider when navigating their own relationships to various social groups (Nesdale, 2004; Verkuyten & de Wolf, 2007). From an early age, children identify and affiliate with social groups (Killen & Rutland, 2011). While memberships to groups can lead to positive developmental outcomes, including identification with others and a sense of belonging, these group memberships can also enable stereotypes, biases, and prejudice that infiltrate children’s social contexts and negatively impact their intergroup relationships (Cooley, Elenbaas, & Killen, 2016; Horn & Sinno, 2014).

Children’s preferences for others are often influenced by group membership, and these biases appear early in life (Kinzler & Spelke, 2011; Newheiser, Dunham, Merrile, Hoosain, & Olson, 2014). In fact, research has demonstrated the emergence of both implicit and explicit forms of prejudice from childhood to adulthood (Levy, Lytle, Shin, & Hughes, 2015). Children as young as 5 years will share more toys with unknown individuals who match their own race than with those of different races (Kinzler & Spelke, 2011), and preschool-aged children preferentially allocate resources to racial ingroup characters instead of racial outgroup characters (Renno & Shutts, 2015). Moreover, in some cases young children show implicit ingroup bias to the same magnitude as adult counterparts (Baron & Banaji, 2006; Dunham, Baron, & Banaji, 2006).

Child-instigated prejudice commonly manifests within peer contexts, as children have biases and stereotypes that affect their interactions with diverse peers. One way in which prejudice invades peer interactions is through intergroup peer inclusion and exclusion, which is when children selectively include or exclude those they perceive to be part of their ingroup identity (Abrams et al., 2009; Møller, & Tenenbaum, 2011). Particularly, children may make decisions about whom to include or exclude from their social contexts and peer groups due to stereotypes and biases about those who are different. Intergroup peer exclusion thus represents a distinct experience from interpersonal peer rejection, in which child is excluded due to personality characteristics (such as shyness or social withdrawal) (Rubin, Bukowski, & Parker, 2006). When children exclude their peers solely because of group membership characteristics, such as their race, gender, or ethnicity, this reflects a form of prejudice (Horn & Sinno, 2014).

It is important to identify the cases in which intergroup peer exclusion occurs because the avenues for remediation are unique from instances of individual-based peer rejection (e.g., excluding someone due to their shyness). When a child is excluded due to personality characteristics, individual-level programs focusing on improving the social skills of the rejected child are often most effective (Bierman, 2004; Rubin et al., 2006). However, in cases of intergroup peer exclusion, the child’s personality characteristics are not the motivating factor for rejection, instead, the child is rejected due to their social group membership. Cases of intergroup peer exclusion are best remediated with group-level programs targeted at reducing prejudice and bias among the excluders, who are often members of the majority group (Rutland & Killen, 2015).

Intergroup peer exclusion decisions are often multifaceted and complex. In some cases, children negatively evaluate excluding someone due to their social group membership, prioritizing moral concerns for fairness, equal treatment, and the well-being of others (Ruck & Tenenbaum, 2014). However, when circumstances become more difficult or ambiguous, prejudicial attitudes and condoning of outgroup exclusion may prevail (Cooley et al., 2016; Killen, Henning, Kelly, Crystal, & Ruck, 2007). Research has investigated developing changes in children’s coordination of inclusive and exclusive preferences through evaluating moral concerns, group identity, group norms, and stereotypic assumptions. In fact, both children and adolescents will promote fairness, justice, and equality in many situations while expressing partiality for their ingroup in other cases. Therefore, it is important to consider the context of a particular scenario, as it may strongly influence how and when ingroup biases are applied to peer exclusion decisions (Mulvey, 2016). Particularly, contexts that include complex or intimate choices about peer relationships, employ stereotypes about outgroups, or create a perceived threat to the ingroup often reveal prejudice and lead to intergroup peer exclusion. In these complex situations, children will often prioritize ingroup functioning or cite their right to personal choice to justify decisions to exclude outgroup members from their peer groups or activities.

Some decisions to exclude outgroup members relate to children’s desire to protect group functioning or access to resources (Rutland & Killen, 2017). For example, adolescents are more likely to include classmates from the same school than from another school into their clubs or activities, citing concerns for maintaining a well-functioning group (Mulvey, Hitti, Rutland, Abrams, & Killen, 2014). Peer pressure from ingroup members may also instigate children’s exclusion of outgroup members, even when these individuals share group norms. Additionally, when resources are restricted or sparse, or groups are in competition, children and adolescents may prioritize ingroup access over concerns for fairness and equality. In one study, children and adolescents were exposed to either competitive or cooperative peer group norms (McGuire, Manstead, & Rutland, 2017). Children and adolescents who were exposed to a competitive group norm were much more likely to show ingroup bias in their allocation of resources than their counterparts who had been exposed to a cooperative group norm, especially when that norm indicated the presence of a competitive outgroup. Thus, children and adolescents are influenced by concerns for ingroup functioning, and these concerns may override preferences for fairness and equality between groups. In these contexts, the provocation of prejudicial attitudes and subsequent intergroup peer exclusion are possible.

Children and adolescents may also justify decisions to exclude outgroup members by citing their freedom of choice for their relationships. For example, intimate and dating relationships are often explained in terms of personal choice, and thus children and adolescents are often more accepting of intergroup peer exclusion within these contexts than in other, less intimate contexts (Edmonds & Killen, 2009). However, concerns for personal choice may also be used to reject biased or exclusive peer group norms. In one study, children and adolescents read a vignette in which a child excluded a racial outgroup peer due to concerns that ingroup members might be uncomfortable (Cooley, Burkholder, & Killen, 2019). Those who negatively evaluated the exclusion were more likely to emphasize the need for autonomy and personal choice in friendship selections than were children who thought exclusion was acceptable. Thus, in certain contexts concerns for personal choice may be used to justify exclusion, however, reasoning about autonomy may also lead children to reject peer pressure and support the inclusion of diverse peers.

Intergroup peer exclusion decisions are often influenced by the context within which the child is operating, as well as by the child’s orientation toward concerns about fairness, group functioning, or autonomy. While in some scenarios, children may emphasize inclusion due to moral or personal concerns, in other contexts prejudice and ingroup bias may influence children’s preferences to exclude diverse peers in order to protect group functioning and access or to protect personal choice in intimate contexts. Moreover, children’s decisions to include or exclude peers may be differentially impacted by the specific group membership considered relevant to the peer context.

Differing Expectations for Exclusion

Children differentially evaluate the wrongfulness (or acceptability) of excluding peers when different group memberships are highlighted. This is because some group memberships may be viewed as a more acceptable basis for exclusion than other group memberships. For example, although children and adolescents view both gender and racial exclusion as wrong, they judge excluding someone because they are a girl less negatively than excluding someone because they are African-American (Killen, Lee-Kim, McGlothlin, & Stangor, 2002). This may be because social and cultural messages about gender roles and gender segregation in childhood are relatively common, while exposure to explicit racism in childhood may be less frequent (Killen et al., 2002).

Moreover, children often view excluding members of groups for which they hold explicit stereotypes more positively than for groups in which explicit stereotypes are not as prominent (Burkholder, Elenbaas, & Killen, 2019; Hitti & Killen, 2015). In one study, non-Arab American adolescents predicted whether their ingroup (American) would include an outgroup (Arab) peer (Hitti & Killen, 2015). Participants who reported stereotypes about Arabs expected that the American peer group would be less inclusive toward the Arab child than did children who did not report stereotypes about Arabs. Therefore, children’s explicit stereotypes about Arabs impacted their predictions of intergroup peer inclusion.

Stereotypes about groups may also impact how children expect others to behave in intergroup peer exclusion contexts. It has been shown that, with age, children increasingly expect high wealth groups to exclude others, and they justify their predictions by referencing negative stereotypes about high wealth individuals’ entitlement or rudeness (Burkholder et al., 2019). Many individuals are members of more than one group, however, and in the case of race and wealth, it is important to make comparisons by including both group memberships. Using a design in which children evaluated the exclusion of peers based on race (with the same wealth background) or exclusion based on wealth (with the same racial background), children evaluated exclusion based on wealth as more acceptable than exclusion based on race (Burkholder et al., 2019). Further, children from African-American and European-American backgrounds use more stereotypes about wealth groups than racial groups when justifying evaluations of exclusion (Burkholder et al., 2019). Thus, negative stereotypes about groups may influence children’s predictions and evaluations of exclusion, as well as their expectations of others’ exclusiveness.

While context is important in understanding children’s predictions and evaluations of intergroup peer exclusion, it is also necessary to consider the impact of the specific group being considered for exclusion. Some group memberships, such as a child’s gender, may serve as a basis for explicit exclusion more often than group memberships such as race (Killen et al., 2002). Moreover, children’s stereotypes about a particular group may influence their condoning of exclusion of individuals due to that group membership. However, while children’s predictions and evaluations of intergroup peer exclusion are influenced by the target’s relevant group membership, it is also the case that the child’s own group membership (and associated experiences) impact their decisions within these contexts.

Minority and Majority Perspectives

Research has documented that minority and majority status children often have different perspectives on intergroup inclusion and exclusion (Burkholder et al., 2019; Cooley et al., 2019; Killen et al., 2007; Theimer, Killen, & Stangor, 2001). In a study with 9- to 14-year olds, European-American children were less likely to expect interracial inclusion to occur than their African-American peers (Cooley et al., 2019). Moreover, African-American children judged interracial exclusion to be more wrong than did European-American children (Cooley et al., 2019). Ethnic minority adolescents have also been shown to be less accepting of common excuses given for interracial exclusion (such as parental or peer pressure), evaluating exclusion in those more complex situations as less acceptable and using more moral reasoning than their European-American counterparts (Killen et al., 2007).

Increased evaluations of the wrongfulness of exclusion have also been documented in other intergroup exclusion contexts in which both minority and majority status perspectives have been collected. In a study with preschool children, boys were more likely than girls to condone inter-gender exclusion in gender-stereotypic activities, such as when playing with dolls and trucks (Theimer et al., 2001). Moreover, girls evaluated exclusion of a female character from a male-stereotypic activity more negatively than did boys, whereas the same pattern was not found for boys’ evaluations of exclusion of male characters in female-stereotypic activities (Theimer et al., 2001). Finally, older children and adolescents who identified as lower in wealth evaluated exclusion on the basis of wealth more negatively than did children who identified as higher in wealth (Burkholder et al., 2019).

Thus, membership to a minority status group, such as an ethnic, gender, or wealth minority group, may tune children into the wrongfulness of exclusion on the basis of that category. Indeed, there is evidence that minority status children’s unique exposure to conversations about prejudice and personal experiences with rejection due to their group membership may influence their negative evaluations of intergroup exclusion (Beaton et al., 2012; Killen et al., 2007). Interestingly, contexts in which gender is highlighted may promote minority status (in this case, female) children’s increased negative evaluations of inter-gender exclusion developmentally prior to this pattern forming in race or wealth exclusion contexts. This may be because gender is a concrete category that is clearly labelled for children at a young age (Killen et al., 2002), whereas complex understanding of other intergroup memberships like race or wealth status may solidify later in development.

Children’s intergroup inclusion and exclusion judgments are influenced by their social group membership, ingroup bias and prejudice, as well as moral concerns for fairness and equality. While in some situations children promote fairness and inclusion, in other contexts children fall back on prejudice and bias against outgroups. Therefore, it is essential to understand the contexts and social group memberships at play, as well as how children’s own group memberships may influence their decisions and evaluations. Moreover, it is important to understand how to promote positive intergroup relationships and encourage affiliation between groups.

Intergroup Contact and Friendships

Contact with diverse groups in childhood decreases bias, prejudice, and discrimination, including negative forms of intergroup exclusion and peer interactions (Allport, 1958; Crystal, Killen, & Ruck, 2008; Pettigrew & Tropp, 2006; Tropp & Pettigrew, 2005). Intergroup contact, under specific conditions, is essential for reducing bias and prejudice (Allport, 1958; Dovidio, Glick, & Rudman, 2005; Pettigrew & Tropp, 2006). These conditions, which must be met to successfully reduce prejudice and bias through intergroup contact, include equal status between groups, shared common goals, the presence of authority sanctions (e.g., parents and teachers who support the inclusion and integration of diverse peers), and intergroup friendships (Dovidio et al., 2005; Pettigrew & Tropp, 2006).

Extensive empirical work has confirmed that intergroup friendships, in particular, are one of the best predictors for reducing prejudice (Crystal et al., 2008; Tropp & Pettigrew, 2005). Children attending racially integrated schools hold less racial biases on average than children attending racially segregated schools (Feddes, Noack, & Rutland, 2009; Jugert, Noack, & Rutland, 2011), and European-American children with higher levels of interracial friendships are more likely to indicate a strong potential for future friendship with African-American peers than their counterparts with low levels of contact (McGlothlin & Killen, 2010).

Moreover, there is evidence that having cross-group friendships decreases implicit bias in childhood (McGlothlin & Killen, 2010). European-American children who did not report having cross-race friendships showed negative implicit bias when predicting characters’ intentions in an ambiguous context. Specifically, these children were significantly more likely to assume that an African-American character had negative intentions when viewing an ambiguous context than they were when viewing a European-American character in the same context (McGlothlin & Killen, 2010). However, children who indicated that they had cross-race friendships did not show this same bias. Instead, they did not use racial group information to predict positive or negative intentions in the ambiguous context (McGlothlin & Killen, 2010). Thus, interracial friendships are not only an avenue to create positive intergroup contact but also reduce bias and prejudice in childhood.

Unfortunately, intergroup friendships, particularly interracial friendships, remain relatively rare in childhood, and the rate of intergroup friendships declines dramatically by early adolescence (Aboud, Mendelson, & Purdy, 2003). On the other hand, predictions that others will choose ingroup members as friends over outgroup members increase with age (Roberts, Williams, & Gelman, 2017; Shutts, Roben, & Spelke, 2013), as do predictions of intergroup social exclusion (Crystal et al., 2008; Killen et al., 2002).

For example, by 4 years old European-American children begin to predict that racial and gender ingroup members would be friends over outgroup members (Shutts et al., 2013), and this effect is exacerbated among European-American children attending ethnically homogenous schools with low levels of intergroup contact (McGlothlin & Killen, 2010). Low levels of intergroup contact are also related to reductions in ethnic majority children’s expectations for interracial inclusion and increased acceptance of interracial social exclusion (Crystal et al., 2008; Ruck, Park, Crystal, & Killen, 2015; Ruck, Park, Killen, & Crystal, 2011).

It has also been argued that cross-group friendships are more beneficial for reducing prejudice for majority group members (e.g., high-status groups from middle-income backgrounds) than for minority group members (e.g., underrepresented minority groups) (Dixon, Durrheim, & Tredoux, 2007). This is because high-status majority groups have less contact with minority groups, and friendships provide a way for reducing stereotypic associations for high-status groups. Yet, it is also important to determine what types of intergroup contact experiences facilitate less prejudice and a greater sense of belonging for minority individuals, as well as for collective social action (Dixon, et al., 2007). In childhood, most data has focused on majority groups for reducing prejudice. However, some findings indicate that intergroup contact is also helpful for reducing prejudice among minority groups (Ruck, Park, Crystal, & Killen, 2015), and the recognition of rectifying inequalities (discussed below) emerges for both majority and minority racial groups when both groups view racial inequalities as wrong and unfair (Elenbaas & Killen, 2016).

It is clear that group membership becomes a relevant factor that children and adolescents consider when predicting and evaluating intergroup social exclusion, predicting others’ friendship choices, and creating their own friendships. Thus, intergroup social exclusion and the patterns of cross-group friendships remain important topics for study.

Prejudice, Bias, and Perceptions of Similarity

Research has suggested that, with age, children may prioritize group functioning over intergroup friendships due to perceptions that individuals of different groups do not share similarities (Stark & Flache, 2012). In fact, children often justify the absence of intergroup friendships due to lack of shared interests with outgroup members or shared common goals with ingroup members (Hitti & Killen, 2015; Stark & Flache, 2012). Children and adolescents also relate comfort with others with group membership. For example, adolescents often reference a sense of comfort with racial ingroup members when condoning interracial exclusion (Killen, Kelly, Richardson, Crystal, & Ruck, 2010), and thus this sense of comfort may play an increasing role in friendship choice over this developmental period. Moreover, there is evidence that children and adolescents with low interracial contact use race-based stereotypes to justify their sense of racial discomfort (Killen et al., 2010).

When given only information about group membership (such as racial or gender group membership), children rate ingroup members as more similar than outgroup members (Doyle & Aboud, 1995; Shutts et al., 2013). While many group memberships motivate perceptions of (dis)similarity, the developmental trajectory of these assumptions may be different. For example, preschool-aged European-American children were more likely to use gender as evidence for similarity than race (Shutts et al., 2013). By 6 years old, the majority of European-American children consider race when predicting similarity between pairs, but the percentage of children predicting similarity based on racial group membership again decreases by 9 years old (Doyle & Aboud, 1995). Thus, gender and race both become important pieces of information for children’s perceptions of similarity during these childhood years, however these perceptions emerge and peak at different developmental time-points (Doyle & Aboud, 1995).

It is also important to note that biases about similarity are often measured in scenarios where participants were presented with no information about characters other than their group identity. When given additional information, such as shared interests between characters, children are overall less likely to use group membership as an indicator for similarity (McGlothlin, Killen, & Edmonds, 2005). For example, in one study European-American children judged comparisons between cross-race pairs with shared interests as very similar to each other, while also rating same-race pairs with different interests as very dissimilar from each other. However, European-American children also rated African-American characters who did not share interests as more similar than European-Americans who did not share interests. Therefore, it may be that children’s biased perceptionsof similarity in many studies were, at least partially, due to the fact that there was no other information which could be utilized to assess similarity. However, while children may focus more heavily on shared interests than group membership when given that additional information, biases about outgroup members still appear to be present.

One finding of this study (McGlothlin et al., 2005) was that participants assumed individuals were more similar to each other when they shared an outgroup membership (such as two African-American characters when the child was European-American). In fact, outgroup homogeneity, or the idea that ingroups have high individual-level variability while outgroups are relatively uniform, has been linked to prejudicial biases in childhood and adolescence (Hitti & Killen, 2015; Stark & Flache, 2012). Perceptions that outgroups do not have much individual variation can have damaging effects on children’s intergroup relationships (Stark & Flache, 2012). Even when attending ethnically diverse schools, children who attribute similar interests across ethnic outgroups were less likely to indicate potential for cross-group friendships than children who did not hold outgroup homogeneity biases (Stark & Flache, 2012).

Moreover, in a study investigating how perceptions of similarity factor into peer group choices (Hitti & Killen, 2015), non-Arab American adolescents expected ingroup members to be inclusive of Arab American characters who shared the group’s interests. However, they also expected that the Arab American peer group would prioritize ethnic identity over shared interests due to perceptions that Arab Americans would prefer to only associate with ethnic ingroup members (Hitti & Killen, 2015). This perception that ingroup members would be accepting of outgroup peers while outgroup members would be exclusive is highly problematic, as it diminishes possibilities for positive intergroup relationships while placing the blame on the outgroup (Hitti & Killen, 2015).

As children gain exposure to groups, biases and prejudices develop through perceptions of similarity of ingroup members, perceptions of dissimilarity between groups, and biases about outgroup homogeneity (McGlothlin et al., 2005; Hitti & Killen, 2015; Stark & Flache, 2012). These increasing perceptions of dissimilarity between members of different groups may be related to developing knowledge of stereotypes (Bigler & Liben, 2007; Hitti & Killen, 2015). As children get older and gain more exposure to their social worlds, they also continue to develop stereotypes about outgroup members (Bigler & Liben, 2007; Killen & Rutland, 2011). Previous research has linked the endorsement of stereotypes to prejudice, discrimination, and bias in both childhood and adulthood (e.g., McKown, 2004). These stereotypes about outgroup members become more internalized over childhood and into adolescence (Rutland & Killen, 2015). There is evidence that children and adolescents who hold negative stereotypes about outgroups are also more likely to condone race-based exclusion (Hitti & Killen, 2015) and gender-based exclusion (Theimer et al., 2001). Therefore, it may also be the case that negative outgroup stereotypes increasingly impact children’s perceptions of outgroup members, leading them to be cautious about exploring potential intergroup friendships.

Mental State Knowledge as Necessary for Rejecting Prejudicial Behavior

Recent research has revealed that, in addition to developing stereotypes and biases about outgroups, prejudice in childhood is also motivated by a lack of understanding the perspectives of these outgroups (McLoughlin & Over, 2017). In fact, the ability to recognize that others have beliefs, desires, intentions, and perspectives which may differ from one’s own, an ability called mental state knowledge or “theory of mind” (ToM) (Premack & Woodruff, 1978), has been identified as a potential candidate to help children counter prejudice. ToM allows children to more readily understand the behaviors and motivations of those who are different from themselves. Thus, it is believed that ToM also aids in the ability of children to recognize members of the outgroup as individuals with their own beliefs, intentions, and desires rather than just seeing them as a reflection of the larger group (Chalik, Rivera, & Rhodes, 2014; Rizzo & Killen, 2018a).

Evidence for the role of ToM in children’s ability to counteract prejudicial beliefs and biases can be found in the ways children react to information which either supports or contradicts gender stereotypes. In a study investigating the effect of ToM on young children’s stereotypical expectations of gender, 3- to 6-year-old children evaluated scenarios about characters who had toy preferences that defied stereotypical gender norms (e.g., a boy who wanted to play with a tea set and a girl who wanted to play with a truck) (Mulvey, Rizzo, & Killen, 2016). Children with ToM were more likely to expect that characters would stand up to the group and suggest playing with the counter-stereotypic activity. Moreover, ToM ability was also related to children’s increased expectations that they would support this character in their request to play with the counter-stereotypic toy. Thus, young children’s ToM played a meaningful role in predictions that individuals would deviate from expected group behavior and affected how supportive children would be of another individual attempting to behave in a way which challenged stereotypes. In this way, ToM ability was associated with an increased likelihood to accept and to support those who challenge the stereotypes which often underlie prejudicial attitudes.

In another study investigating the role of ToM in children’s evaluations of gender-stereotypic activities, 4- to 6-year-old children were told stories in which characters assembled toys either adhering to stereotypically male (blue trucks) or female (pink princess dolls) gender norms (Rizzo & Killen, 2018b). Performance on the task varied, with some characters producing several toys and some characters producing few. Following the story, children gave out prizes based on the character’s performance. In scenarios where males did better at making trucks or females did better at making princess dolls (consistent with gender stereotypes), children gave more to the character who did a better job, and theory of mind didn’t impact children’s reward distribution. However, in counter-stereotypic contexts, where the female character did a better job at making blue trucks or when the male character did a better job making pink princess dolls, ToM ability predicted children’s distributions of awards. Children with higher levels of ToM gave more to the meritorious and counter-stereotypic character than did children with a less developed ToM ability, suggesting that children who had a more fully developed ToM competency were better able to separate the performance of a character from gender stereotypes. Therefore, there is evidence that ToM is associated with children’s ability to counter biased expectations based on prejudice and instead reward individuals based on more appropriate indices, such as their merit.

Theory of mind ability is a powerful tool which may help children reject stereotypes, and this ability continues to develop throughout childhood (D’Esterre, Rizzo, & Killen, 2019). Children who are better able to identify and attend to the information relevant to understanding intentions and desires may have less need to rely on other, irrelevant information such as race, gender, or nationality. However, children’s reaction to a situation is impacted by their position within that context. Young children demonstrate an understanding of stereotypes which are relevant to their own group identities (Muzzatti & Agnoli, 2007) and their behavior changes in response to these stereotyped expectations (Neuville & Croizet, 2007). This asymmetry in the ways in which situations are perceived will necessarily also create differences in perspectives, beliefs, and feelings regarding the same situation, and there is evidence to suggest that these have an impact on children’s stereotype-based behavior.

Moreover, children’s status within a context affects their ability to take others’ perspectives. Recent research on the role of children’s advantaged or disadvantaged status on reasoning has shown that children are actually less receptive to the mental states of others when they find themselves in an advantaged situation (Rizzo & Killen, 2018a). Other studies have found that children who are in disadvantaged situations tend to be less likely to endorse stereotypes (Killen, Kelly, Richardson, & Jampol, 2010) and display less biased behavior (McGlothlin & Killen 2010). One possible reason for this pattern of results is that as children attend more heavily to the mental states of others, they are more likely to focus on those individual factors and less on group membership.

The ability for young children to counter stereotypes is, at least partially, dependent on their ability to understand the mental states of those who are different from them (McLoughlin & Over, 2017) and to recognize the individuality of members of outgroups (Chalik et al., 2014; Rizzo & Killen, 2018a). This understanding of the differences between and within groups puts children in a position to counteract stereotypes and prejudicial behavior. As children develop the ability to understand the perspectives of outgroup members, they are increasingly able to challenge norms, which are unfair to these groups (Mulvey & Killen, 2016; Mulvey & Killen, 2017), and to counteract group-based inequalities (Elenbaas, Rizzo, Cooley, & Killen, 2016).

Challenging Prejudice and Unfair Treatment

While children’s developing awareness of groups often leads to stereotypes, biases, and prejudice, knowledge about groups is not always negative. In fact, there is emerging evidence that children’s group knowledge also can promote positive intergroup relationships and advocacy for fair treatment of all individuals, including equitable resource distributions and standing up against prejudicial treatment in peer contexts (Killen et al., 2016; Palmer & Abbott, 2018). These studies suggest that, in some cases, developing intergroup knowledge can promote positive intergroup relations. Moreover, children’s emerging conceptions of fairness and equality are applied to intergroup contexts as children begin to recognize moral values as ones that are relevant for all individuals (Turiel, 2002).

Rectifying Group-Level Resource Inequalities

Recognition of status differences between groups can influence children’s reasoning about the unfairness of social disparities (Arsenio, Preziosi, Siberstein, & Hamburger, 2013; Chafel & Neitzel, 2005). This knowledge leads to understanding about what makes differential treatment of others based on group membership unfair and unequal (Elenbaas & Killen, 2016). It is clear that in many cases children view inequality as unfair (Arsenio et al., 2013; Chafel & Neitzel, 2005; Elenbaas & Killen, 2016). In one study, 5–6- and 10–11-year-old children were introduced to a group-based inequality in access to school resources (Elenbaas et al., 2016) to determine whether children were more likely to rectify or perpetuate an inequality of resources. Children viewed a resource disparity in which one group (European-American schools or African-American schools) received many more resources than the other (both contexts were presented to all participants). While younger children gave more resources to the disadvantaged group when it was their ingroup than when it was their outgroup (showing evidence of an ingroup bias), with age, children increasingly allocated resources to the disadvantaged group regardless of whether they shared the group’s membership. In this study, this meant that, with age, all children (African-American and European-American) allocated more resources to disadvantaged Black school than to disadvantaged White schools. These studies show that, with age and in certain contexts, children use their group knowledge about inequality to prioritize equity between groups rather than solely benefiting their ingroup (Elenbaas et al., 2016).

There is also evidence that children’s knowledge about the systematic nature of group disparities may play a role in their negative evaluations of inequalities and may even influence children’s choices to rectify existing social disparities (Elenbaas & Killen, 2016). With age, children are increasingly aware that different racial groups (such as African Americans and European Americans) have different levels of status and wealth generally (Elenbaas & Killen, 2016; Olson, Shutts, Kinzler, & Weisman, 2012). Moreover, children use this group-level knowledge to evaluate resource disparities among groups.

In one study, children who reasoned about differential treatment between groups judged the inequality more negatively than did children who perceived inequalities as a function of institutions’ differing needs, revealing a link between children’s awareness of discrimination and rejection of social inequalities (Elenbaas & Killen, 2017). By middle childhood, children showed an awareness economic inequalities among racial groups often underlie groups’ differential access to societal resources. Children attributed inequalities to differential treatment of racial groups more when they observed a disadvantaged African-American group than when they observed a disadvantaged European-American group, providing evidence of an understanding of the broader societal factors contributing to restricted access to resources (Elenbaas & Killen, 2017). This suggests that children’s assessments of the origin of inequality influence their evaluations of resource inequalities based on race.

In a similar study, African-American and European-American children between the ages of 5–6 and 10–11 years old evaluated a race-based medical resource inequality (Elenbaas & Killen, 2016). With age, children chose to rectify the inequality (by giving the disadvantaged group more medical resources), but importantly only when the disadvantaged group was African-American. When the European-American group was disadvantaged, children allocated the resources equally between groups. Therefore, children’s broader group-level knowledge influenced their assessments of inequalities, providing evidence that, with age, children may evaluate some disparities within the larger context of society (Elenbaas & Killen, 2016).

Yet it is important to note that awareness of the existence of group inequalities, and even the desire to rectify those inequalities, is not incompatible with research assessing children’s stereotypes, prejudice, and biases based on group membership. In a study by Li, Spitzer, and Olson (2014), preschoolers elected to reduce an existing inequality while also expressing preference for the advantaged character. Moreover, even while evaluating inequalities negatively, with age children increasingly predict that higher status groups will prioritize self-serving interests in access to resources due to negative stereotypes (such as selfishness or greed) that may influence their evaluations (Elenbaas & Killen, 2018). These findings emphasize the complexity of children’s understanding of groups, specifically that social knowledge about groups can simultaneously generate both positive outcomes, such as advocacy for fairness, and negative outcomes, such as stereotypes, biases, and prejudice.

Rejecting Prejudice in Peer Contexts

In addition to utilizing group knowledge to negatively evaluate and rectify inequalities of resources, children also apply group membership knowledge in peer contexts to remediate existing prejudicial treatment. Specifically, there is evidence that knowledge about groups, including awareness of prejudice and discrimination, influences children’s evaluations of exclusion and bullying based on group membership (Mulvey, Palmer, & Abrams, 2016). In one study, ethnic majority children and adolescents evaluated the wrongfulness of race-based humor. Children who negatively evaluated the humor referenced the welfare and rights of the victimized outgroup peer and were more likely to label the humor as a form of discrimination or prejudice (Mulvey et al. 2016).

Children and adolescents also support challenging unfair group norms, such as norms supporting unequal allocation of resources, relational aggression, or physical aggression toward outgroups (Mulvey & Killen, 2016; Mulvey & Killen, 2017). Moreover, studies assessing intergroup peer bullying show that in the majority of cases, children and adolescents reject outgroup victimizing behavior and endorse prosocial bystander actions, such as intervening on behalf of the victimized peer (Palmer, Cameron, Rutland, & Blake, 2017; Palmer, Rutland, & Cameron, 2015). Prosocial actions decrease with age, however, with children endorsing prosocial bystander actions more than did adolescents (Palmer et al., 2015, 2017). Moreover, ingroup bias has been recorded in these contexts. Specifically, children and adolescents were most likely to assume positive bystander intentions when the victimized peer was an ingroup member and the aggressor was an outgroup member (Palmer et al., 2015). Thus, these studies exemplify the complex interplay between children’s developing understanding of groups and group-level inequalities, peer contexts, and prejudice.

Summary and Key Points

As communities around the world become more diverse, it is especially important to understand how children’s perceptions and knowledge about groups lead to prejudice and bias, as well as how prejudice infiltrates peer contexts. In addition, as there are many instances of children forgoing differences to promote acceptance of diverse others and rectification of prejudice and inequalities, it is equally important to investigate the circumstances that allow children to overcome ingroup biases to accept those who are different.

Children reason about morality, group identity and functioning, and personal preferences to either support or condemn prejudicial attitudes. In childhood, prejudice may be enacted through intergroup peer inclusion and exclusion, stereotypes about outgroup members, and bias about similarity between ingroup members. However, group knowledge and the awareness of social hierarchies, in some cases, can lead to the rejection of prejudice and the promotion of fairness for all parties. Intergroup friendships and mental state knowledge both play a role in combatting prejudice in childhood, as both encourage children to view outgroup members as individuals and not just as products of their group membership.

In light of this research, we recommend a four-pronged approach to reduce prejudice in childhood. First, it is necessary to promote shared interests to facilitate common ingroup identity (beyond physical appearance and cultural membership) and foster cross-group friendships as they enable children to challenge stereotypes and reject exclusion. Second, moral reasoning promoting fairness and equality in intergroup contexts needs to be highlighted and encouraged. Children have strong views about fairness; however, they need help understanding when such values and judgments must be applied to individuals who might not share their group identity. Third, enhancing mental state knowledge of diverse others is crucial. This includes helping children to understand that others have feelings, beliefs, and desires different from one’s own. Fourth, creating positive conditions of intergroup contact, both direct and indirect, will reduce prejudice and promote a recognition of fair treatment of others.

Facilitating positive intergroup relationships in childhood is essential for the global, diverse world that we live. By adulthood, prejudice and bias often become entrenched, and thus these negative attitudes are difficult to remediate. However, childhood represents a time of marked growth and change and thus is an ideal place to target prejudices as they begin to emerge. Reducing prejudice in childhood will not only create more positive relationships among diverse peers but will have long-term positive effects as children grow into adults and gain access to societal-level decisions, such as fair allocations of goods and services and the reduction of systematic discrimination based on group membership. Reducing prejudice in childhood therefore creates healthy children and a more just and civil society.