Systematic Review:
The Effects of Classroom Heterogeneity on Students' Socio-Emotional Experiences

Theory

Many theories have been developed that either set out to describe the impact of group heterogeneity on social and psychological outcomes or have implications for this link. Based on a review of relevant theories from developmental psychology, social psychology, sociology and politics, we have developed an integrated theoretical model of the effects of classroom heterogeneity on psycho-social outcomes.

The model describes how classroom heterogeneity on different dimensions is associated with student socio-emotional outcomes.It enumerates ten pathways by which classroom heterogeneity can impact students' psycho-social outcomes.

Heterogeneity

The model doesn't specifically focus on any dimension of heterogeneity. Most pathways can in principle apply to different dimensions of heterogeneity.

The different symbols within the box "Heterogeneity" are signifying that heterogeneity as a term can have different conceptual meanings and implications for measurement, which are, for example, described by Harrison and Klein (2007). In our review of theories, we identified three relevant dimensions of heterogeneity: Firstly, multiplicity, which alludes to the sheer number of different categories present in a classroom. Secondly, the distance between groups or persons: groups can be very similar and close to each other, but they can also spread across a large range. Thirdly, the theme of balance vs. imbalance between groups is a central one, especially to intergroup theories.

Psycho-social outcomes

The focus in our review of theories was on theories that predict psycho-social outcomes. The targeted outcomes include affective, cognitive and behavioral outcomes, including peer relations. Examples for affective outcomes are school belonging, classroom climate, or subjective social integration. Cognitive outcomes include different interpersonal skills, but also stereotypes. Behavioral outcomes can be aggression, bullying and victimization, but also pro-social behavior and peer support. Also, relationships in the classroom, like number of friends and inter-group friendships, but also homophily, i.e., ingroup-orientation, are included in the review.

Pathways

The pathways by which classroom heterogeneity is hypothesised to cause the outcomes are labeled according to the direction of their influence (P-positive and N-negative). Each pathway is connected to one or more theories from the research fields mentioned above. The symbols next to the pathway signify the conceptualization of heterogeneity which is implicated by the respective theories. In the following, each pathway is shortly described.

N1 - Polarization. Socio-constructivist theorists, like Vygotski and Piaget, emphasize that learning takes place in social interaction with others. Here, differences can have a positive impact in that they stimulate children to exchange their views and ideas and develop more advanced concepts (see below P1). However, if students' prior knowledge and experiences are too different, they might not be able to relate to each other anymore, thus leading to less mutual understanding and ultimately, a polarization in outcomes. For these theories, outcomes are typically in the cognitive realm.

N2 - Self-enhancement. This pathway is described in Tajfel and Turner's Social Identity Theory. This theory posits that humans try to achieve a positive identity by forming groups along a salient social category and then valuing their in-group and de-valuing the outgroup(s). Which identity is salient in a certain situation can be moderated by contextual clues (M1), like teachers emphasizing a dimension of comparison in the classroom, but also by the composition of the class. Thus, low to medium levels of heterogeneity are often seen as causes for saliency of this dimension.

N3 - Norm deviation. This pathway is described by models suggesting negative outcomes for individuals who deviate from a group norm, like the Social Misfit or Person-Group Similarity Model (Wright, 1986) and also Social Comparison Theory (Festinger, 1954, Schachter, 1952). Here, persons deviating from a group norm will have lower status in this group and might even face rejection.

N4 - Vulnerability. Students who belong to a numerical minority in the classroom might be more vulnerable, because they might have less social support than students belonging to a greater group. This is described in Olweus' (1992) Imbalance of Power Thesis. These more vulnerable students are more prone to be victimized by members of the majority group.

N5 - Status conflicts. Contrary to Olweus, Blalock (1967) in his Group Threat Theory predicts that conflict and violence between groups is highest when groups are equally represented and motivated to fight for supremacy.

N6 - Social disintegration. Mostly originating from the study of politics (Constrict Theory, Putnam, 2007) and criminology (Social Disorganization Theory, Shaw & McKay, 1942), this view supposes that in contexts of high diversity (in the sense of ethnic heterogeneity and social inequalities), a missing common identity leads to the dissolution of social control and a break-down of social norms. This in turn creates higher levels of crime and violence and less trust in society.

P1 - Productive heterogeneity. This pathway is based on the aforementioned socio-constructivist theories. Differences are productive in that they throw children in a state of cognitive disequilibrium which they are motivated to resolve by actively engaging in problem-solving, perspective-taking, and dialogue with their peers. This process encourages deeper understanding, critical thinking, and the development of more advanced cognitive frameworks, ultimately fostering intellectual growth and social learning (e.g., of social skills).

P2 - Unity through heterogeneity. This argument proposes that a maximum of heterogeneity will (in the long run) lead to more solidarity and the development of alternative identities that could serve to unite people instead of separating them (Putnam, 2007).

P3 - Protective heterogeneity. Mirroring P4, the idea here is that in a situation in which no clear majorities exist, students are more likely protected from being victimized.

P4 - Opportunity for contact. Finally, in his Structural Theory, Blau (1974) observes that a higher level of heterogeneity increases the opportunity for contact between members of different groups. More contact, provided that it occurs under the right conditions (M4), should lead to more understanding and a reduction of stereotypes.

Methods

We conducted a systematic review, adhering to PRISMA guidelines, where appropriate.

Literature Search

Databases

We used PsychInfo (psychology), Scopus (social science) and ERIC (education).

Search strategy

We searched title and abstract for keywords combining heterogeneity, psycho-social outcomes and context.

Sub-string heterogeneity(toggle for full string)▼

“classroom diversity” OR “diverse classroom” OR “diverse classrooms” OR “class diversity” OR “diverse class” OR “diverse classes” OR “school diversity” OR “diverse school” OR “diverse schools” OR “student diversity” OR “peer diversity” OR “diverse peer” OR “diverse peers” OR "diverse composition" OR "diverse grouping" OR “achievement diversity” OR “diverse ability group” OR “diverse ability groups” OR “diverse ability grouping” OR “diverse achievement” OR “ethnic diversity” OR “racial diversity” OR “cultural diversity” OR “social diversity” OR “socioeconomic diversity” OR “socio-economic diversity” OR “SES diversity” OR “language diversity” OR “linguistic diversity” OR “classroom heterogeneity” OR “heterogeneous classroom” OR “heterogeneous classrooms” OR “class heterogeneity” OR “heterogeneous class” OR “heterogeneous classes” OR “school heterogeneity” OR “heterogeneous school” OR “heterogeneous schools” OR “student heterogeneity” OR “peer heterogeneity” OR “heterogeneous peer” OR “heterogeneous peers” OR "heterogeneous composition" OR "heterogeneous grouping" OR “achievement heterogeneity” OR “heterogeneous ability group” OR “heterogeneous ability groups” OR “heterogeneous ability grouping” OR “heterogeneous achievement” OR “ethnic heterogeneity” OR “racial heterogeneity” OR “cultural heterogeneity” OR “social heterogeneity” OR “socioeconomic heterogeneity” OR “socio-economic heterogeneity” OR “SES heterogeneity” OR “language heterogeneity” OR “linguistic heterogeneity” OR “classroom homogeneity” OR “homogeneous classroom” OR “homogeneous classrooms” OR “class homogeneity” OR “homogeneous class” OR “homogeneous classes” OR “school homogeneity” OR “homogeneous school” OR “homogeneous schools” OR “student homogeneity” OR “peer homogeneity” OR “homogeneous peer” OR “homogeneous peers” OR "homogeneous composition" OR "homogeneous grouping" OR “achievement homogeneity” OR “homogeneous ability group” OR “homogeneous ability groups” OR “homogeneous ability grouping” OR “homogeneous achievement” OR “ethnic homogeneity” OR “racial homogeneity” OR “cultural homogeneity” OR “social homogeneity” OR “socioeconomic homogeneity” OR “socio-economic homogeneity” OR “SES homogeneity” OR “language homogeneity” OR “linguistic homogeneity” OR “classroom mix” OR “mixed classroom” OR “mixed classrooms” OR “class mix” OR “mixed class” OR “mixed classes” OR “school mix” OR “mixed school” OR “mixed schools” OR “student mix” OR “peer mix” OR “mixed peer” OR “mixed peers” OR "mixed composition" OR "mixed grouping" OR “achievement mix” OR “mixed ability group” OR “mixed ability groups” OR “mixed ability grouping” OR “mixed achievement” OR “ethnic mix” OR “racial mix” OR “cultural mix” OR “social mix” OR “socioeconomic mix” OR “socio-economic mix” OR “SES mix” OR “language mix” OR “linguistic mix” OR “classroom similarity” OR “similar classroom” OR “similar classrooms” OR “class similarity” OR “similar class” OR “similar classes” OR “school similarity” OR “similar school” OR “similar schools” OR “student similarity” OR “peer similarity” OR “similar peer” OR “similar peers” OR "similar composition" OR "similar grouping" OR “achievement similarity” OR “similar ability group” OR “similar ability groups” OR “similar ability grouping” OR “similar achievement” OR “ethnic similarity” OR “racial similarity” OR “cultural similarity” OR “social similarity” OR “socioeconomic similarity” OR “socio-economic similarity” OR “SES similarity” OR “language similarity” OR “linguistic similarity” OR “classroom dissimilarity” OR “dissimilar classroom” OR “dissimilar classrooms” OR “class dissimilarity” OR “dissimilar class” OR “dissimilar classes” OR “school dissimilarity” OR “dissimilar school” OR “dissimilar schools” OR “student dissimilarity” OR “peer dissimilarity” OR “dissimilar peer” OR “dissimilar peers” OR "dissimilar composition" OR "dissimilar grouping" OR “achievement dissimilarity” OR “dissimilar ability group” OR “dissimilar ability groups” OR “dissimilar ability grouping” OR “dissimilar achievement” OR "different achievement" OR “ethnic dissimilarity” OR “racial dissimilarity” OR “cultural dissimilarity” OR “social dissimilarity” OR “socioeconomic dissimilarity” OR “socio-economic dissimilarity” OR “SES dissimilarity” OR “language dissimilarity” OR “linguistic dissimilarity” OR “classmate diversity” OR “diverse classmate” OR “diverse classmates” OR “classmate heterogeneity” OR “heterogeneous classmate” OR “heterogeneous classmates” OR “classmate homogeneity” OR “homogeneous classmate” OR “homogeneous classmates” OR “classmate mix” OR “mixed classmate” OR “mixed classmates” OR “classmate similarity” OR “similar classmate” OR “similar classmates” OR "multiethnic schools" OR "multiethnic classrooms" OR "multiethnic classes" OR "multiracial schools" OR "multiracial classrooms" OR "multiracial classes" OR "multicultural schools" OR "multicultural classrooms" OR "multicultural classes" OR "gender diversity" OR "gender heterogeneity" OR "gender homogeneity" OR "gender mix" OR "mixed genders" OR "gender similarity" OR "gender dissimilarity"

Sub-string outcomes(toggle for full string)▼

"antisocial behavior" OR "antisocial behaviors" OR "antisocial behaviour " OR "antisocial behaviours " OR "attachment" OR "belonging" OR "belongingness" OR "bullying" OR "classroom climate" OR "classroom connection" OR "classroom connections" OR "classroom contact" OR "classroom interaction" OR "classroom interactions" OR "classroom relation" OR "classroom relations" OR "classroom relationships" OR "coethnic connection" OR "co-ethnic connection" OR "coethnic connections" OR "co-ethnic connections" OR "coethnic contact" OR "co-ethnic contact" OR "coethnic interaction" OR "co-ethnic interaction" OR "coethnic interactions" OR "co-ethnic interactions" OR "coethnic relation" OR "co-ethnic relation" OR "coethnic relations" OR "co-ethnic relations" OR "coethnic relationship" OR "co-ethnic relationship" OR "coethnic relationships" OR "co-ethnic relationships" OR "coethnic understanding" OR "co-ethnic understanding" OR "cohesion" OR "collaboration" OR "connectedness" OR conflict* OR "cooperation" OR "cross-ethnic connection" OR "cross-ethnic connections" OR "cross-ethnic contact" OR "cross-ethnic interaction" OR "cross-ethnic interactions" OR "cross-ethnic relation" OR "cross-ethnic relations" OR "cross-ethnic relationship" OR "cross-ethnic relationships" OR "cross-ethnic understanding" OR "cross-group connection" OR "cross-group connections" OR "cross-group contact" OR "cross-group interaction" OR "cross-group interactions" OR "cross-group relation" OR "cross-group relations" OR "cross-group relationship" OR "cross-group relationships" OR "cross-group understanding" OR "cross-racial connection" OR "cross-racial connections" OR "cross-racial contact" OR "cross-racial interaction" OR "cross-racial interactions" OR "cross-racial relation" OR "cross-racial relations" OR "cross-racial relationship" OR "cross-racial relationships" OR "cross-racial understanding" OR "empathy" OR "ethnic segregation" OR "exclusion" OR friendship* OR "gender segregation" OR help* OR "inclusion" OR "intercultural connection" OR "intercultural connections" OR "intercultural contact" OR "intercultural interaction" OR "intercultural interactions" OR "intercultural relation" OR "intercultural relations" OR "intercultural relationship" OR "intercultural relationships" OR "intercultural understanding" OR "interethnic connection" OR "inter-ethnic connection" OR "interethnic connections" OR "inter-ethnic connections" OR "interethnic contact" OR "inter-ethnic contact" OR "interethnic interaction" OR "inter-ethnic interaction" OR "interethnic interactions" OR "inter-ethnic interactions" OR "interethnic relation" OR "inter-ethnic relation" OR "interethnic relations" OR "inter-ethnic relations" OR "interethnic relationship" OR "inter-ethnic relationship" OR "interethnic relationships" OR "inter-ethnic relationships" OR "interethnic understanding" OR "inter-ethnic understanding" OR "intergroup connection" OR "inter-group connection" OR "intergroup connections" OR "inter-group connections" OR "intergroup contact" OR "inter-group contact" OR "intergroup interaction" OR "inter-group interaction" OR "intergroup interactions" OR "inter-group interactions" OR "intergroup relation" OR "inter-group relation" OR "intergroup relations" OR "inter-group relations" OR "intergroup relationship" OR "inter-group relationship" OR "intergroup relationships" OR "inter-group relationships" OR "intergroup understanding" OR "inter-group understanding" OR "interpersonal competence" OR "interracial connection" OR "inter-racial connection" OR "interracial connections" OR "inter-racial connections" OR "interracial contact" OR "inter-racial contact" OR "interracial interaction" OR "inter-racial interaction" OR "interracial interactions" OR "inter-racial interactions" OR "interracial relation" OR "inter-racial relation" OR "interracial relations" OR "inter-racial relations" OR "interracial relationship" OR "inter-racial relationship" OR "interracial relationships" OR "inter-racial relationships" OR "interracial understanding" OR "inter-racial understanding" OR "majority-minority connection" OR "majority-minority connections" OR "majority-minority contact" OR "majority-minority interaction" OR "majority-minority interactions" OR "majority-minority relation" OR "majority-minority relations" OR "majority-minority relationships" OR "mobbing" OR "non-cognitive skills" OR "peer acceptance" OR "peer connection" OR "peer connections" OR "peer integration" OR "peer interaction" OR "peer interactions" OR "peer neglection" OR "peer pressure" OR "peer rejection" OR "peer relation" OR "peer relations" OR "peer relationship" OR "peer relationships" OR "prosocial behavior" OR "prosocial behaviors" OR "prosocial behaviour " OR "prosocial behaviours" OR "psychosocial development" OR "psychosocial functioning" OR "racial segregation" OR "relatedness" OR "school climate" OR "school connection" OR "school connections" OR "school integration" OR "school interaction" OR "school interactions" OR "school relation" OR "school relations" OR "school relationship" OR "school relationships" OR "school violence" OR "sociability" OR "social acceptance " OR "social behavior " OR "social behaviors" OR "social behaviour" OR "social behaviours" OR "social competence" OR "social competencies" OR "social competent behavior" OR "social competent behaviors" OR "social competent behaviour" OR "social competent behaviours" OR "social connection" OR "social connections" OR "social engagement" OR "social functioning" OR "social integration" OR "social interaction" OR "social interactions" OR "social involvement" OR "social isolation" OR "social neglection" OR "social network" OR "social networks" OR "social rejection" OR "social relation" OR "social relations" OR "social relationship " OR "social relationships" OR "social segregation" OR "social sensitivity" OR "social skills" OR "social ties" OR "social-emotional development" OR "soft skills" OR "soft-skills" OR "support" OR "sympathy" OR "teasing" OR "tolerance" OR "trust" OR "victimization" OR "well-being"

Sub-string context(toggle for full string)▼

Sub-string context

AND class* OR school* OR student* OR pupil*

Eligibility criteria

• Publication date: 1990-2021 (update currently in progress)
• Sample: primary or secondary school students
• Methodology: quantitative
• Independent: classroom heterogeneity (assessed by heterogeneity indices)
• Dependent: Psycho-social characteristics and relationships
  • affective (e.g., attachment, belonging, classroom climate)
  • behavioral (e.g., victimization, violence, support, cooperation, contact, peer relations, including intergroup-relations)
  • cognitive (e.g., social skills, attitudes, stereotypes)

Selection

Title and abstract screening was done by trained research assistants, with 15% double coding and insecurities and differences resolved by consesus. Find the full list of references that have been identified so far here. Full text screening and coding was conducted by trained research assistants in tandem with a doctoral or post-doctoral researcher, that is, each paper was coded by two persons.

Results

The poster contains descriptive results on the studies from our review.

1. Studies originate from diverse research fields (see poster Fig. 3)
2. Studies refer to different pathways (see poster Fig. 4)
3. Most studies do not make a definite prediction about the direction of results, but are rather exploratory (see poster Fig.4)

Additional preliminary results - Evidence Map

Here, results of the studies are broken up by dimension of heterogeneity (ethnic, achievement, ses, language, sen and gender) and outcome domain. The share of studies which yielded a positive result is green, red are the studies with negative results and grey are studies with null-results. It is apparent that for ethnic heterogeneity, no clear picture emerges, while achievement, ses and language heterogeneity show mostly negative consequences of heterogeneity. Note that the number of studies varied widely, which is symbol. Only one study looked at heterogeneity in special educational needs and showed a positive effect, and one study considered heterogenous composition of gender in classrooms and found no significant result.

Download the Poster