Since Kohlberg (1966) introduced the concept of gender constancy, the idea that gender is a stable individual trait that develops in early childhood has prevailed in developmental psychology. Gender constancy stems from limited binary and cis-centric notions of gender: Gender is assumed to be ‘stable’ or ‘constant’ because it is seen as something inherent, biological, and that aligns with the gender youth were assigned at birth. This conceptualization stems from a flawed theoretical perspective and fails to capture the lived experiences of gender-expansive youth. Unfortunately, most longitudinal studies have aligned with this perspective so that we know almost nothing about potential gender changes in adolescence and early adulthood. This study therefore explored 1) whether and how frequent changes in gender identity occur and 2) what these changes look like. As part of an eight-wave longitudinal study, a community sample of Dutch adolescents and early adults (N = 933; Mage = 18.70, SD = 4.04) reported their gender identity in at least two waves. We examined the prevalence of gender changes and what patterns of change emerged. Results showed that approximately one out of 20 youth changed their gender identity at least once, with several youth changing their gender identity multiple times over the scope of the study. Whereas some youth changed between binary options (i.e., boy/man or girl/woman), others (also) considered nonbinary options – either by identifying as nonbinary or with various self-descriptions. We also showed that youth used other ways to communicate potential gender-expansiveness, including self-describe and ‘prefer not to say’ options and through missing data patterns. Our findings thus highlight gender as a dynamic and contextual identity that changes across the lifespan. These findings have clear implications for the field of developmental psychology and practical recommendations will be discussed.

Diversity is a crucial part of nowadays children’s and adolescents’ socialization who grow up in constant interaction with a multilayered context of intertwined contextual layers – with all layers permeated by culture. Accordingly, the psychological experience of diversity does not exist outside of, or around a person, but rather is the product of a person-context-interaction. Given this complexity in diverse contexts, a recent review encouraged scholars to broaden our repertoire of school racial/ethnic diversity measures to better understand the subtleties of diversity. Towards this end, this study introduces two diversity indices that can capture two distinct aspects of diversity based on languages: the class diversity index – the static component of diversity - and the student diversity index - the dynamic component. First, we tested the robustness of these indices by a number of simulations. Second, we tested whether these indices were associated with student (self-efficacy & classroom climate) and teacher (teacher emotions & beliefs about achievement) outcomes. The sample comprised 933 students (Mage = 13.30, SD = 1.38; 41% female) and 28 classroom teachers (Mage = 45.93, SD = 11.58) from 48 classrooms in Germany. To test the robustness of indices, we performed simulations by removing an increasing number of students from classes. As expected, the class diversity index was less affected in these simulations than the student diversity index. Furthermore, the student diversity index was associated with better student outcomes (self-efficacy and classroom climate), whereas the class diversity index showed a higher likelihood of teachers to perceive fear and anger and less enjoyment as well as more agreement to ability and socio-economic status achievement beliefs. Findings highlight the importance of diversity as a multifaceted construct as well as the perceived challenges German teachers report in teaching diverse classes.

Traditional research on religious diversity in childhood has primarily relied on parental reports or assessed children’s attitudes toward religious outgroups. However, little is known about how young children actively acquire and process knowledge about religions beyond their own. Building on prior findings that outgroup religious understanding moderates children's intergroup prosocial behavior, this study takes a novel approach by directly assessing young children’s knowledge of an unfamiliar minority religion (i.e., Muslim prayer practices) using developmentally appropriate, one-on-one tasks with a majority-Catholic sample. Additionally, by incorporating theory-of-mind (ToM) as a cognitive moderator, this study investigates individual differences in how children integrate religious knowledge. A sample of 183 young children (Mage = 4.18, SD = 0.97) completed the structured measuring outgroup religious understanding and ToM, while parental religiosity was assessed via questionnaires. Moderation analysis (PROCESS Model 1), controlling for age, revealed that ToM abilities significantly moderated the effect of parental religiosity, such that higher parental religiosity predicted lower outgroup religious understanding only in children with higher ToM, whereas no effect was found for children with lower ToM. These findings offer a new perspective on how young children engage with religious diversity, highlighting the cognitive mechanisms that shape early interfaith knowledge. By directly assessing children’s understanding of a religious outgroup rather than relying on parental reports, this study highlights innovative pathways for fostering inclusivity in early childhood education.

Extant theories about ‘wear and tear’ articulate that psychological stress responses to discrimination deteriorate individuals’ health. However, empirical studies seldomly capture whether these stress responses predict decrements in health, as they mostly examine the ‘tear’ or direct impact of discrimination without capturing the cumulative effects of psychological stress responses following discrimination. This oversight can bias conclusions as meta-analyses have concluded that discrimination is unrelated to physical health. We propose a novel statistical approach that captures ‘wear and tear’ using intensive and non-intensive longitudinal data, wherein we predict that degree to which discrimination predicts mental health (i.e., a random slope) will predict epigenetic age acceleration (i.e., a biomarker of healthy human aging). We drew data from two national longitudinal datasets: one sample of 397 aging adults (77% White, 23% non-White; 58% female, 42% male; M-age_baseline=53.11, SD=12.79) who completed daily diaries in the Midlife in the United States, and a second sample of 2,059 aging adults (65% White, 35% non-White; 58% female, 42% male; M-age_baseline=61.42, SD=9.64) who completed five biannual surveys in the Health and Retirement Study. Across both studies, adults who experienced more discrimination based on various social categories (i.e., ethnicity/race, gender/sex, age, weight) than their average also reported worse psychological adjustment, such as greater depressive symptoms and negative affect. This psychological impact of discrimination was associated with more epigenetic age acceleration in the DunedinPoAm and DunedinPACE clocks. These results support the depiction of ‘wear and tear’ and yield recommendations for interventions targeting allostatic load in populations susceptible to discrimination.