Advanced Review
The development of stereotyping
and exclusion
Kelly Lynn Mulvey, Aline Hitti and Melanie Killen∗
This article reviews the developmental science literature on stereotyping and
exclusion, with a focus on gender, race, and ethnicity. Stereotyping of others,
which is defined as the attribution of traits to individuals based on group
membership, is often used to justify exclusion of others in social group contexts.
This review includes a focus on the links between these two constructs. Research on
stereotyping and exclusion has drawn on several theoretical traditions, including
social domain theory, social identity developmental theory, and subjective group
dynamics theory, which are also discussed in the context of the research
findings. Key findings on stereotyping include categorization and classification in
relationship with decreased in-group bias, and the role of stereotypes in encoding
information. Findings on exclusion include the use of available information to make
judgments, preferences for in-group members who are normative and out-group
members who are deviant, the increased importance, with age, of group functioning
in exclusion decisions, and decreased negative evaluation of in-group members
who partake in exclusionary behaviors. Though little research has explicitly studied
the links between stereotyping and exclusion from groups, this review describes
the current literature in both areas and suggests future directions for research. 
2010 John Wiley & Sons, Ltd. WIREs Cogn Sci 2010 1 597–606
S
tereotyping emerges in childhood and contributes
to processes related to inclusion and exclusion.
This is because exclusion from groups is often justified
on the basis of stereotypic expectations.1–3 Individuals
who do not fit the stereotypic expectations of a
group (and the group identity) are vulnerable to
being rejected and excluded by the group. Because
exclusion is related to negative social consequences
in childhood and adulthood, it is important to
understand how and why stereotyping emerges in
development, and the links to processes of exclusion.
This review of the developmental science literature
will focus on stereotyping and exclusion in childhood
and adolescence, and provide a foundation for
understanding issues of prejudice in development.
Stereotyping reflects cognitive categorizing
about the world. Cognitive structures include one’s
perception of beliefs, knowledge, and expectations
about different social groups,4–7 which develop during
∗ Correspondence
to: [email protected]
Department of Human Development, 3304 Benjamin Building,
University of Maryland, College Park, MD, 20742, USA
DOI: 10.1002/wcs.66
Vo lu me 1, Ju ly /Au gu s t 2010
childhood and play a role in how children and
adults reason about and interact with others. Social
psychologists focus on stereotypes as the cognitive
components influencing intergroup behaviors. In this
review,8 due to space limitations, we will focus on
cognitive and social-cognitive aspects of stereotyping
and exclusion rather than including emotional and
affective dimensions as well.
Stereotypes play a fundamental role in discriminatory actions, such as exclusion from peer groups,
which children and adolescents experience throughout
their lives. Inclusion and exclusion in an intergroup
context, which is defined as an interaction with members of an out-group3 occurs when children relate to
their peers in different ways based on their group membership, such as their ethnicity or gender.1 Although
not necessarily detrimental, exclusion can have longterm negative impacts on children who are excluded;
for instance, exclusion can lead to long-lasting struggles with depression, anxiety, and social withdrawal.1
Research on stereotyping in childhood has
typically centered on gender as well as race/ethnicity.
Although there is a long history of studying stereotypes
about gender and race/ethnicity in adult contexts,9
less is known about the connection between the
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development of stereotyping and exclusion based on
gender and race/ethnicity in childhood. The study
of the development of stereotyping and exclusion
in childhood is based on developmental theories
of cognition, including social-cognition and moral
judgment. Beginning with Piaget (1932/1965), the
field has differentiated into several recent frameworks.
For this review, we will focus on two theoretical
models, social domain theory10,11 and social identity
theory.12
THEORETICAL FOUNDATIONS
OF STEREOTYPING AND EXCLUSION
RESEARCH
Piaget (1932/1965) conducted foundational research
on the development of social cognition, which he
defined as the thought process required for making
judgments about the morally correct action in a
specific situation. A lack of a moral viewpoint
inevitably leads to prejudice, given that acting on
prejudicial beliefs, such as those often embodied in
stereotyping, violates moral principles of equality and
fairness.13 Thus, Piaget’s research on the development
of moral principles is relevant for understanding
the emergence of stereotyping and exclusion. Piaget,
relying on an interview methodology, determined
that children’s morality develops as an outcome of
social and cognitive abilities. As children begin to
interact with others and form peer relationships, they
develop more complex understandings of equality,
reciprocity, and respect. Piaget’s work, in particular,
his focus on the importance of peer relationships in
the development of moral reasoning in children, bears
on the study of stereotyping and exclusion as these
arise in the context of peer interaction and intergroup
relations.
Social domain theory11,14 builds from this
early theory with its focus on social cognition but
deviates from the global stage model by (1) providing
a domain-specific account of social development
and (2) demonstrating the emergence of morality in
early childhood. Extensive research has determined
that children’s social reasoning is organized by
three domains, the moral, social–conventional, and
psychological, which co-occur in development and
do not reflect an ordered hierarchical, stage-like
trajectory.11,15 Research driven by this theory has
shown that children from a very young age (3 years)
construct their thinking about the social world by
differentiating their experiences based on either the
moral domain, which includes actions that have
implications for someone else’s welfare, fairness,
justice, and rights; the social–conventional domain,
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which includes actions that are contingent on socially
agreed upon rules that are alterable and that, in their
absence, will cause no direct harm to be inflicted on
another; or the psychological domain, which includes
actions related to personal choices and preferences
(for a review of theory refer to Smetana (2006)). A
key element of social domain theory, which holds
relevance for the study of stereotypes and exclusion,
is the central focus on children’s reasoning and
the recognition that children do distinguish, from
very early ages, between behaviors and acts which
inherently center on issues such as fairness and justice
and those which promote group functioning and
social interactions (for a review, see Killen, Sinno,
and Margie (2007)). This theory has been applied to
the topic of stereotyping and exclusion in several ways,
as described below, with the predominant focus being
the forms of reasons (e.g., moral, social–conventional,
psychological) children and adolescents use to justify
or reject exclusion decisions, and how stereotyping
is explained by children using social–conventional
reasons (e.g., traditions, customs, norms). Moreover,
exclusion and stereotyping research has centered on
contextual variations, stemming from social domain
theory, to understand when and how these constructs
emerge in development.
While moral principles are required to reject
exclusion based on stereotyping, group identity
emerges during childhood, which provides a competing consideration for children, one that has the
potential to enhance stereotyping of others. A central theoretical framework which bears on the study
of stereotypes, exclusion, and social groups is social
identity theory.12 According to social identity theory,
individuals strive to maintain their in-group identity
by viewing their own social group more positively
than other social groups, and to identify with social
groups with positive social status. Attempts to see
the in-group in increasingly positive ways can lead
to prejudice toward members of out-groups.12 Selfcategorization theory (SCT Turner et al.,16 ) extends
this concept of self-identification on the basis of
cognitive grouping.2 Therefore, people place themselves in a group that they view as most similar
to themselves based on some classification label,
which is cognitively contrasted with another classification. Such self-categorization emphasizes positive
similarities between individuals of the in-group, thus
promoting in-group bias, while also focusing on the
negative differences of the out-group which may lead
to out-group prejudice. This process, then, creates
opportunities for the development of stereotypes and
acts of exclusion based on group membership.3
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STEREOTYPING AND
CATEGORIZATION AS PRECURSORS
OF EXCLUSION
Research, specifically, on stereotyping has framed
stereotypes as linked to the ability to cognitively
organize the social world into categories and examines
how stereotypes are used to rationalize behavior with
respect to these categories.17–19 In a study on in-group
favoritism and out-group prejudice with 4–7 year
olds, Aboud20 found correlations between children’s
classification skill and their scores on the Preschool
Racial Attitude Measure.21 Children who had higher
multiple classification skills, and were thus able to
classify stimuli into multiple categories, displayed
lower in-group favoritism.20 Thus, this study indicated
that, in fact, children’s ability to classify may help
to mitigate the development of stereotypes. This is
because children were able to simultaneously attribute
both positive and negative attributes to the same child,
decreasing out-group negativity.
Bigler and Liben18 tested a similar hypothesis
considering the effects of teaching children (5–10 years
of age) multiple classification skills on gender
stereotyping and information processing. Further
supporting Aboud’s20 finding that classification skill
may decrease stereotyping, prior to the intervention,
a significant positive correlation was found between a
child’s classification skills and their egalitarian gender
attitudes.18 After intervention, results showed that
those children who acquired multiple classification
skills and who were trained specifically on social
categories improved the most on their egalitarian
responses.
In a measure assessing participants’ memory
for occupations that were gender counter-stereotypic,
those who were better classifiers remembered more
counter-stereotypic information than those who were
not. This did not differ between those who received
training classifying social categories or those who were
trained with non-social categories, thus suggesting
that multiple classification skills help children to
process counter-stereotypic information even if they
have stereotypic attitudes. In another study assessing
individual differences in memory of race-related
stereotype-consistent versus stereotype-inconsistent
information, Bigler and Liben19 found another
correlation between 4- and 9-year-old children’s
classification skills and their ability to process specific
information.
Using a classification task that included race,
gender, and age as possible categories Bigler and
Liben19 found that children’s ability to classify was
negatively correlated with their stereotypic responses.
They also concluded that the problem children had
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recalling counter-stereotypic information is highly
correlated with both children’s racial stereotyping and
their classification skills, and not related to a child’s
poor attention, or lower intelligence.19 Therefore,
children’s retrieval of information about a category
or group is influenced by stereotypes and their ability
to classify an individual into one or multiple groups.
Yet, while children become capable of classification,
stereotyping persists into adulthood.2,22 Thus, other
explanations are required to explain the trajectory of
stereotyping through development.
Stereotype research with adults suggests that
people use stereotypes as recall cues.23 Stereotypes are
used when both encoding and retrieving information
thus increasing the number of associative paths to
stereotypic information.24 Similar processes may be at
work in children’s stereotyping processes as well. The
relation between stereotypes and memory in children,
however, has mostly been studied in the context
of children’s eye-witness testimony. Young children’s
encoding, storage and retrieval of information about
events are highly influenced by stereotypes and
interviewer suggestibility.25 Two studies that assess
the effects of stereotypes on children’s testimony
propose that it is the schematic nature of stereotypes
that helps children remember them.25,26 Stereotypes
provide information about individuals, which assist
children in organizing their memory of specific
categories or groups. Research on recollection of
categories has shown that children do use schemas
to help them remember, and are more likely to
remember thematic categories based on functionality
than taxonomic lists.27
This thematic nature of stereotypes facilitates the
encoding of information collected from experiences
or the environment, and helps with retrieving
information from memory. Stereotypes may also add
to information that has not been perceived and
misrepresent information that has been perceived.28 It
is worth noting that the relationship between memory
and stereotypes is twofold; while on the one hand,
stereotypes influence a child’s memory, the processes
and strategies used to remember also lend themselves
to schematic biases that in turn invoke stereotypes.
These memory processes to some extent facilitate the
use of stereotypic information in children’s judgments.
However, memory as well as judgment is also driven
by the inferences that people make based on what they
know. This has been documented when adolescents
evaluate peer retribution: in a study which showed
that when participants were asked to make judgments
about punishment based on ambiguous information,
adolescents were more likely to rate punishment
for stereotype-consistent transgressions (e.g., jocks
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breaking the sound system at a party) as more fair than
stereotype-inconsistent transgressions (e.g., computer
club members breaking the sound system at a party).29
Drawing on previous literature concerning
people’s concepts of intelligence and its impact on
self-judgment, Dweck et al.30 , Dweck and Leggett,31
Levy and Dweck32 applied the idea of the lay person’s
static (entity) versus dynamic (incremental) theory
to children’s stereotyping. They hypothesized those
who adopt an entity theory and view their social
structures as fixed are more likely to stereotype,
while those who adhere to an incremental theory
and understand their social structures to be malleable
are less likely to stereotype. Examining this theory in
adults and 11–13 year olds,32,33 findings showed that
entity theorists who believed that people’s attributes
are fixed displayed higher levels of stereotyping
than incremental theorists who thought of people’s
attributes as malleable. Studies about the impact of
people’s lay theories on stereotype formation based
on realistic groups have been conducted only with
adults, however, and limited research exists with
children.33,34
Recent research has suggested that these implicit
theories about intelligence are one component of a
broader phenomenon referred to as essentialism.35
Essentialism, the tendency to assume shared invisible
traits are held by all members of a group,36,37 may also
be at play in some instances of stereotyping,33,38 which
can lead to exclusion. A focus on essentialist beliefs
appears to impact the development of stereotypes as
well as prejudice in certain contexts because essentialism involves generalizing characteristics of an entire
group to an individual member of the group. Such
generalizations can function to create stereotypes.38
EXCLUSION AND GROUP NORMS
Another explanation for the continuation of stereotyping into adolescence and adulthood lies with the role
that stereotyping plays in perpetuating group identity, group norms, and exclusion.1,3 Moreover, social
conventional reasoning, identified by social domain
theory, often serves to justify stereotyping. Social identity theory proposes that enhancing the group requires
in-group favoritism and out-group negativity.3 Outgroup negativity may generate stereotyping as well as
prejudice and bias. Children frequently base decisions
on who to include based on what they believe about
others, which is often founded upon the stereotypes
that have developed as described above. Studying the
social reasoning used by children as they make inclusion and exclusion decisions helps to unveil precisely
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what role stereotypes and stereotypic information
plays in this process.
Recent research on exclusion has focused
on children’s social and moral cognition, drawing
on social domain theory11,15 to investigate the
reasoning used by children in making inclusion and
exclusion decisions. The methods used in social
domain research provide a platform for testing
children’s judgments about social and moral issues
in an intergroup context.13 Participants in this line
of research are asked to judge and reason about
hypothetical scenarios of fairness and justice in
which the target’s group membership is manipulated.
Children and adolescents have been shown to elicit
the use of stereotypes when making their judgments
about inclusion and exclusion1 as well as peer
retribution,29,39 attributing intentions of others,40
explaining intergroup discomfort,41 and initiating
cross-group and cross-race friendships.42,43
When asked to judge prototypic or straightforward exclusion scenarios based on group membership,
such as gender and race/ethnicity, preschool aged
children are more likely to evaluate exclusion as
wrong using equality and fairness reasons than using
social–conventional or personal justifications or relying on stereotypes.1,44,45 In complex or ambiguous
situations, however, children and adolescents will rely
on stereotypes.1 For instance, Theimer, Killen, and
Stangor (2001) analyzed European American children’s (mean age ∼ 6 years) evaluation of inclusion in
an activity based on gender-stereotypic expectations
of peer activities (e.g., doll-playing, truck-playing).
Results showed that in the absence of additional information about experience with the activity, participants
chose to include the child who fit the stereotype of the
activity more often and used stereotypic reasoning in
justifying their answers (e.g., ‘Boys don’t know how
to play with dolls and dolls are only for girls’ or ‘Girls
are quiet and they don’t like to play with trucks’).
In continuation of this research, Killen et al.44
investigated age differences (3–5 year olds) in assessing
children’s use of stereotypes in reasoning about similar
inclusion scenarios as those used in Theimer, Killen,
and Stangor (2001) and counter-probed children
about their inclusion decision offering them an
alternative reason to include the child they did not
pick, thus testing their conviction in their decision.
Probing revealed that most children who initially used
stereotypic information to make their decision did
change their minds to focus on moral judgment when
given the opportunity (after a probe by the interviewer
in which the fairness of turn-taking was mentioned),
while those who initially focused on the moral aspects
of the situation did not change to consider the
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stereotypic argument as often (after a probe by the
interviewer in which the stereotype about who plays
with toys was mentioned). However, the study did
show that younger children were more likely than
older children to choose the stereotypic child prior to
probing, and were more likely to base their judgment
on stereotypic expectations.
Exclusion based on stereotypes has been studied
with older children as well as in multifaceted
scenarios, where children must weigh multiple types
of information in making exclusion decisions. Killen
and Stangor (2001) interviewed first, fourth, and
seventh graders, using similar gender-stereotypic
activity-based scenarios (e.g., boys joining a ballet
club and girls joining a baseball team), however
they also included multifaceted scenarios, where
children were given information about the skill
level of the different possible targets for inclusion
and exclusion. They found that children rejected
straightforward exclusion and used moral reasoning
in judging exclusion as wrong. The children generally
chose the non-stereotyped child in the equal skill
context multifaceted situation, which suggests active
inclusivity. Surprisingly, in-group favoritism was
not found. Additionally, the researchers found that
most children only used one type of justification
(social–conventional or moral).
As expected, age-related differences were documented. Specifically, in the unequal skill context,
both first and seventh graders favored the stereotypical child, but fourth graders did not. Most children
used group functioning (social–conventional reasoning) for justifying the unequal skill situation, but
first and fourth graders used more moral reasoning
than did seventh graders. Finally, the study showed
gender differences, with girls showing a greater concern for inclusivity. Overall, the findings indicated
that, with age, group functioning (in the form of
social–conventional reasoning) was provided as a
basis for exclusion.
Horn46 built from this line of research, capturing
the explicit use of stereotypes in making moral
judgments about peer relationships in adolescence.46
Using ambiguity in scenarios presented to ninth and
eleventh graders that focused on peer cliques (e.g.,
the ‘cheerleaders’ excluded a ‘gothic,’ the ‘jocks’
excluded a ‘techie’), Horn46 found that such lack
of information influenced the use of stereotypes by
adolescents. In this study when judging a scenario
where only group membership information was
provided, participants were more likely to rely on
either purely moral concerns (‘It’s unfair to exclude the
gothic’) or only stereotypic information (‘A techie is
not athletic’) when making decisions about exclusion
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or distribution of resources. This was compared
with scenarios where information about individual
merit was given. In ambiguous scenarios, adolescents
relied on whatever information was available to
make judgments, thus stereotypes served as a source
of information. Thus, Horn’s research reveals how
complexity, such as multiple considerations, and
ambiguity, such as a lack of individuating information,
contribute to stereotyping by adolescents regarding
exclusion from social cliques.
More recently, social domain theory on exclusion has focused on race and ethnicity.47 A set of
studies has examined other variables that contribute
to why and how children and adolescents justify or
reject exclusion, including social experience, such as
intergroup contact and cross-race friendships. These
variables stem from both Piagetian theory with his
emphasis on peer interaction and social experience
contributing to social knowledge, as well as social
psychological theory regarding intergroup contact. In
Allport’s17 foundation theory on the nature of prejudice, he hypothesized that a set of conditions need to
be met for intergroup contact to reduce prejudice;48,49
one of the strongest predictors for prejudice reduction
is cross-race friendships.49
Crystal et al.50 tested whether intergroup contact in the form of cross-race friendships was related
to evaluations of interracial peer exclusion. Using
three contexts that varied in intimacy (friendship,
sleepover, dating), the findings indicated that both
ethnic majority and minority participants in fourth,
seventh, and tenth grade viewed interracial exclusion
as more wrong when they had a higher level of intergroup contact, which was a measure that included
contact in classrooms, schools, and neighborhoods.50
In another study, researchers demonstrated that intergroup contact in the form of cross-race friendships was
significantly related to the use of stereotypes by White
European-American students in fourth, seventh, and
tenth grade to explain interracial peer discomfort.41
In this study, participants were asked why it was that
there might be discomfort in interracial interactions.
Students with low reported levels of cross-race friendships were more likely to explain racial discomfort in
terms of stereotypes such as lack of shared interests
and levels of aggressiveness by the out-group than
students with high levels of cross-race friendships.41
Finally, a comparison was made for how
ethnic majority and minority US participants (fourth,
seventh, tenth grades) evaluated interracial peer
encounters in which the purported reason for
exclusion by the excluder was either ‘non-race’ such
as lack of shared interests, or ‘race-based’ such as
explicitly referring to race. Although all participants
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used moral reasons, such as a lack of fairness and
unequal treatment to evaluate race-based exclusion,
there were differences between the majority and
minority samples regarding the ‘non-race’ reasons
for exclusion with minority participants viewing it
as more wrong than majority participants (and using
more moral reasons). For example, minority students
viewed a White student not having lunch with a Black
student because the Black student ‘did not like soccer’
as less wrong than did ethnic majority students,
who viewed this type of decision as a ‘personal
choice’ (in a manner similar to how same-race peer
encounters would be evaluated). Ethnic minority
students referred to reasons such as empathy and
perspective taking, as well as reasons referencing a
lack of fairness to evaluate exclusion as wrong.
Age-related differences emerged regarding the
context. With age, participants viewed exclusion from
a sleepover party as wrong, rejecting parental pressure
to keep a party same-race; at the same time, with
age, participants viewed exclusion from a friendship
encounter as legitimate, accepting peer pressure to
conform to same-race dating expectations. As a
whole, these findings provide information regarding
how stereotypic expectations emerge, and are related
to evaluations of intergroup exclusion. Focusing on
group functioning becomes more salient for children,
with age, and particularly by adolescence. In fact, the
roots of group identity begin in early childhood.
As children begin to associate with social groups,
they develop preferences for different groups based
on behaviors or traits of individuals within those
groups, thus intergroup relations find a foothold in
stereotypic beliefs which children form about other
groups.2,12,51,52 A theoretical framework that has
looked at this process is social identity development
theory (SIDT), which, while focused on ethnic
prejudice, provides a foundation for thinking about
intergroup contact and conceptions of the in-group
and out-group in relation to the self. SIDT proposes
that children move through four phases as they
develop ethnic prejudice: undifferentiated, ethnic
awareness, ethnic preference, and ethnic prejudice.53
SIDT is relevant for studying many forms of exclusion
(ethnic or otherwise) because of its analysis of group
relationships in the ethnic preference phase.
Specifically, according to SIDT, as children
enter the ethnic preference phase, they exhibit a
concern with maintaining membership in the ingroup and a strong focus on the identity of that
in-group.54 SIDT would predict, then, that children
in the ethnic preference phase would adhere tightly
to in-group norms, including any in-group norms of
exclusion, which may lead to both stereotypes and
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prejudicial attitudes toward the out-group and move
them into the ethnic prejudice phase.54 Children ages
4–5 years old, according to SIDT, are likely in the
ethnic preference phase and may be engaging in outgroup derogation.54 The theory proposes that the
development of out-group derogation is dependent
on several factors: the level of identification that a
child has with his/her in-group, the extent to which
prejudice is an in-group norm, and the extent to
which the in-group members perceive the members of
the out-group as a threat.54–56
Nesdale et al.54 assessed SIDT’s prediction that
children would actively dislike out-group members
when the in-group had a norm of exclusion as
well as when out-group threat was present. Their
findings, which revealed that group norms of exclusion
do lead to children developing more prejudicial
attitudes and stereotypes toward the out-group,
provide support for much of SIDT.54 However, they
found age-related changes not accounted for by SIDT:
when the in-group held a norm of exclusion, older
children expressed neutrality toward the out-group,
not outright dislike.54 Research outside of SIDT has
revealed that, with age, children are less likely to
attribute negative traits to the out-group.57 Thus, these
findings reveal that there may be greater complexity
to individuals’ experiences and decision making with
regard to in- and out-groups.
Children use stereotypic information when making decisions about how much they like in- and
out-group members and, therefore, whether they will
include or exclude these members. Nesdale53 conducted a study focused explicitly on how children use
stereotypic information in making judgments about
how much they like or dislike in-group members,
with a focus on ethnic groups. Specifically, 8-, 10-,
and 12-year-old children were told stories about inand out-group members of different ethnic groups
(Australians and Vietnamese) who displayed behavior
that was either stereotype-consistent or stereotypeinconsistent for their ethnic group. Not only did
older children have better memory recall for the ingroup member stereotype-inconsistent information,
but also they liked the out-group member (who
expressed stereotype-inconsistent information) better
than the in-group member who expressed stereotypeinconsistent information. Younger children still preferred the in-group member, even when this member
expressed stereotype-inconsistent information. Thus,
children do actively use stereotypes in making decisions about who they like.
This finding leads directly to the work of Abrams
and Rutland, who have looked explicitly at how
one makes decisions about including or excluding
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in- and out-group members who adhere to or resist
group norms.3 Their work, which has focused on
the intersection of stereotyping and exclusion in an
intergroup context, is founded upon the framework
of subjective group dynamics (SGD). SGD focuses on
group identity and the relationship between judgments
about members of one’s in-group and judgments about
in-groups and out-groups generally.58,59 Specifically,
SGD examines children’s reasoning about in- and outgroup members who express deviant and normative
attitudes toward the group.58
Research has found that children prefer individuals who express normative, or loyal, ideas about
the in-group, regardless of their group affiliation
and likewise express greater dislike for individuals
who deviate from the in-group norms.59 Additionally,
research on SGD has shown that, in moral situations,
children use intergroup bias, which often has its foundations in stereotypes, for group-based evaluations,
but not morality-based evaluations.60 SGD has also
revealed that, with age, children adhere more to group
norms and rely more on group functioning in decision
making.60 Thus, SGD brings to the study of exclusion a focus on the salience of group identity and
an understanding of how individuals evaluate in- and
out-group members who are either loyal or deviant
toward group norms.
Specific findings from within this theoretical
framework illuminate exactly how children use
information about groups, specifically group norms,
in making decisions about who to exclude. In one
study, focused on summer school-based groups, which
are minimal where children have not had time to
form strong bonds or relationships with their ingroup members, Abrams et al.59 found that children
(6–7 year olds and 10–11 year olds) showed a strong
in-group bias, even though the groups were minimal.
Additionally, older children were even more focused
on differentiating their responses to loyal and deviant
in- and out-group members than younger children.
Thus, older children seem better able to consider
multiple categories, which lead to a greater dislike
for group members who deviate from their own ingroup norms and greater like for group members
who support in-group norms. Older children, then, in
some ways are able to overcome their conceptions of
the out-group, which may be based on stereotypes,
and value individual out-group members who express
deviant views, thus supporting the in-group.
Building on this study, researchers found, contrary to earlier suggestions, that multiple classification
skill is not related to intergroup bias.61 In other words,
while children, with age, did develop better multiple
classification abilities, it did not reduce their level
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of intergroup bias. Instead, it seems that with age,
children are even more focused on group dynamics
and their concern with being loyal to group norms
increases, which may perpetuate stereotypes and lead
to greater exclusion. This finding is in contrast to
other SGD work which found that older children
showed decreased racial prejudice and stereotyping,
due to public self-focus. In other words, older children
expressed less intergroup bias because of their perception that adults would not approve of such beliefs.62
Thus, while adults can have a powerful impact on the
explicit expression of prejudicial attitudes, children
seem poised to continue exclusive behavior based on
adherence to group norms.
CONCLUSION
In conclusion, age-related changes regarding stereotyping and exclusion are multiple. A few readily
identifiable patterns are that: (1) with age, explicit
stereotypes diminish in straightforward contexts but
are activated in complex exclusion situations; (2) with
age, multiple forms of reasoning are brought to bear
on exclusion decisions, including moral, conventional,
and psychological reasons; (3) social identity increases
with age and contributes to in-group bias; (4) with age,
an understanding of group dynamics becomes more
complex and knowledge enables children to differentiate in-group identity and social norms which bear
on exclusion; (5) group identity can both foster and
hinder stereotyping, depending on the context; and
(6) social experience in the form of intergroup contact
and cross-group friendships can reduce prejudice and
increase tolerance.
While much research has been conducted investigating the developmental trajectory of stereotypes and
exclusion, there are many gaps to be filled. Further
analysis is needed to understand what drives children’s use of group functioning in their judgments.
Can it be explained by a stereotypic understanding
that only people of the same social category can
function well together in a group, or are there other
reasons? Although the research reviewed touches on
some studies that look at developmental differences
in moral reasoning, there is currently no line of work
that tracks the frequency or contextual relevance of the
use of stereotypes developmentally. Further research
is necessary to document children’s use of stereotypes
in moral reasoning and how this changes cognitively
and contextually from early childhood to adolescence.
This review has mapped the importance of
categorization and classification skills to children’s
use of stereotypes and their egalitarian attitudes.
More research is needed to investigate how and when
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these skills bear on children’s conceptualization of and
theorizing about social exclusion.
It has been found that stereotypes add to or
distort children’s recollection of information, regardless of if the information is factual or false. The
schematic process involved in remembering stereotypes and retrieving them from memory does provide
some insight into the role of memory in invoking
stereotypes in children. However, developmental scientists can draw from the extant and vast research
on stereotypes and memory processes with adults.
Social psychologist have conducted research with a
plethora of samples of university students to investigate the associative-network model and the schemapointer tag model and how they can be applied to
remembering expectancy-congruent and expectancyincongruent information,28 or similarly stereotypeconsistent and stereotype-inconsistent information.
Creating age relevant measures and testing these memory processes in children can help further clarify how
stereotypes are encoded, stored, and retrieved from
memory.
While exclusion literature has drawn extensively
on minimal groups and ethnic groups, more work
should be done drawing out exclusion based on
gender, religion, language, and culture, as these are
areas of continued relevance in the increasingly global
world. By investigating and classifying the reasoning
used by children and adolescents when making inclusion and exclusion decisions, researchers can identify
how children interpret these social experiences, and
thereby reveal the areas for change and intervention.
Ultimately, the application of most of the research outlined above should be in the development of effective
curricula to promote positive intergroup experiences
and to reduce or diminish stereotypes, bias, and discrimination. A greater awareness of the connections
between stereotyping and exclusion will provide an
empirical database for the development of effective
interventions designed to reduce prejudice.
ACKNOWLEDGEMENT
We acknowledge support from the National Science Foundation BCS #0840492.
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FURTHER READING
Abrams D, Hogg MA, Marques JM, eds. The Social Psychology of Inclusion and Exclusion. New York: Psychology
Press; 2005.
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