This longitudinal ecological momentary assessment study examined whether adolescents' use of social media to interact with peers relates to their experiences of social connectedness, social craving, and sensation seeking on an hourly level. Further, we investigated whether these associations differ for adolescents who were nominated by their peers…

This study examines developmental change across adolescence in the similarity of friends versus nonfriends. This differential in similarity is a key aspect of the organization of the peer context of development: The stronger the correlation between friends for an attribute, the more the attribute delineates clustering and divisions of friendships.…

Persistence in high school curricula leading to science, technology, engineering, and mathematics (STEM) careers is structured by complex institutional systems, but developmental processes underlie how young people navigate these systems. This study examined differences in the development of STEM identity and efficacy during high school among…

Achievement goal theory has long been a dominant model in the study of student motivation. However, a relatively small number of researchers have investigated gender differences in achievement goals or have considered the possible role that social and extrinsic goals may play in student academic motivation. Adopting a person-centered multiple…

This study investigated the effects of internal and demographic variables on civic development in late adolescence using the construct "civic purpose." We conducted surveys on civic engagement with 480 high school seniors, and surveyed them again 2 years later. Using multivariate regression and linear mixed models, we tested the main…

Adolescence is a vulnerable period for the initiation and peak of many harmful risk-taking behaviors such as smoking, which is among the most addictive and deadliest behaviors. Generic metatheories like the theory of triadic influence (TTI) suggest that interrelated risk factors across multiple domains (i.e., intrapersonal and…

The current study examined longitudinal cross-lagged associations between prosocial TV (content and time) and prosocial and aggressive behavior during adolescence, and explored the mediating role of empathic concern and self-regulation. Participants were 441 adolescents who reported on their 3 favorite TV shows at 2 time points, approximately 2…

Co-rumination is a dyadic process between relationship partners that refers to excessively discussing problems, rehashing problems, speculating about problems, mutual encouragement of problem talk, and dwelling on negative affect. Although studies have addressed youths' "tendency" to co-ruminate, little is known about the nature of…

The self-equilibrium hypothesis underlines the importance of having a strong core self, which is defined as a high and developmentally stable self-concept. This study tested this hypothesis in relation to body image (BI) trajectories in a sample of 1,006 adolescents (M[subscript age] = 12.6, including 541 males and 465 females) across a 4-year…

A performance-based measure of peer influence susceptibility was examined as a moderator of the longitudinal association between peer norms and trajectories of adolescents' number of sexual intercourse partners. Seventy-one 9th grade adolescents (52% female) participated in an experimental "chat room" paradigm involving…

Social goals are associated with behaviors and adjustment among peers. However, it remains unclear whether goals predict adolescent social development. We examined prospective associations among goals, physical and relational aggression, social preference, and popularity during middle school (N = 384 participants, ages 12-14 years). Agentic…

Prospective longitudinal data from over 14,000 youth residing in 28 communities in the rural United States were analyzed to examine the emergence of mixed-sex friendship groups in early adolescence. Youth were surveyed on 5 occasions between fall of 6th grade and spring of 9th grade. At each assessment, youth reported the names of up to 7…

The developmental trajectory of body image dissatisfaction is unclear. Researchers have investigated sociocultural and developmental risk factors; however, the literature needs an integrative etiological model. In 2009, Cheng and Mallinckrodt proposed a dual mediation model, positing that poor-quality parental bonds, via the mechanisms of…

Applying a person-centered approach, the primary aim of this study was to examine what profiles of schoolwork engagement and burnout (i.e., exhaustion, cynicism, inadequacy) can be identified in high school (N = 979) and among the same participants in young adulthood (ages ranging from 17 to 25). We also examined gender differences, group…

Prevalence, frequency, and psychosocial predictors of Internet and computer game use were assessed with 803 male and 788 female adolescents across 2 time periods, 21 months apart. At Time 1, participants were in the 9th or 10th grade; at Time 2, they were in the 11th or 12th grade. Most girls (93.7%) and boys (94.7%) reported using the Internet at…