Growing up with multiple siblings might negatively affect language development. This study examined the associations between birth order, sibling characteristics and parent-reported vocabulary size in 6163 Norwegian 8- to 36-month-old children (51.4% female). Results confirmed that birth order was negatively associated with vocabulary, yet…

Timing of foster care placement, especially early in life, may have important implications for children's later academic functioning. Given racial disparities in placement decisions, examining associations between age at foster care entry and school outcomes by race is warranted. To address this gap, linked, longitudinal administrative data were…

This longitudinal study examined age- and gender-related differences in autobiographical memory about the COVID-19 pandemic lockdowns and whether the content of these memories predicted psychological adjustment over time. A sample of 247 students (M[subscript age] = 11.94, range 8-16 years, 51.4% female, 85.4% White) was recruited from public and…

Developmental science has increasingly scrutinized how environmental hazards influence child outcomes, but few studies examine how contaminants affect disparities in early skill formation. Linking research on environmental inequality and early childhood development, this study assessed whether differences in exposure to neurotoxic lead explain…

This meta-analysis examined main effects and heterogeneity in associations between popularity and academic adjustment in the U.S. and China across 41 studies. The aggregated sample included 22,151 children and adolescents (10,934 boys; 11,217 girls) from both countries, with U.S. students from various ethnic backgrounds. Results in the U.S. were…

To advance knowledge of critical consciousness development, this study examined age-related change in awareness of inequality by race and ethnicity, gender, parent education, generation status, and their interactions. With longitudinal data (2013-2017) from 5019 adolescents in grades 6-12 (55.0% female) from California, Minnesota, and West…

Adjusting practice to different goals and characteristics is key to learning, but its development remains unclear. Across 2 preregistered experiments, 190 4-to-8-year-olds (106 female; mostly White; data collection: December 2021-September 2022) and 31 adults played an easy and a difficult game, then chose one to practice before a test on either…

Ninety-seven children aged 4-11 (49 males, 48 females, mostly White) were given the opportunity to improve their problem-solving performance by devising and implementing a novel cognitive offloading strategy. Across two phases, they searched for hidden rewards using maps that were either aligned or misaligned with the search space. In the second…

Children's evaluations of empathizers were examined using vignette-based tasks (N = 159 4- to 7-year-old U.S. children, 82 girls, 52% White) between March 2023 and March 2024. Children typically evaluated empathizers positively compared to less empathic others. They rated empathic responses as more appropriate, selected empathizers as nicer, and…

When determining what others know, we intuitively consider not only whether they succeed but also their probability of success in the absence of knowledge (e.g., random guessing). Across three experiments (n = 240 North American 4-6-year-olds, data collected between 2020-2023) we find that 4-year-olds understand that tasks with a lower probability…

The current research examined how seeking versus receiving help affected children's memory and confidence decisions. Baseline performance, when no help was available, was compared to performance when help could be sought (Experiment 1: N = 83, 41 females) or was provided (Experiment 2: N = 84, 44 females) in a sample of predominately White 5-, 7-,…

Across two studies, children ages 6-9 (N = 160, 82 boys, 78 girls; 75% White, 91% non-Hispanic) rated an inaccurate expert's knowledge and provided explanations for the expert's inaccurate statements. In Study 1, children's knowledge ratings decreased as he provided more inaccurate information. Ratings were predicted by age (i.e., older children…

This study examined gender differences in reading behavior of 2652 Danish 5th-grade students (age 10-12 years, girls 51%, 14% immigrant background) observed for 218 days in 2019/2020, using data from a popular reading app. Reading behavior was operationalized as time spent reading. Analyses of timing of reading behavior and models of day-to-day…

Australian children aged 6-9 years (N = 120, 71 females; data collected in 2021-2022) were tasked with remembering the locations of 1, 3, 5, and 7 targets hidden under 25 cups on different trials. In the critical test phase, children were provided with a limited number of tokens to allocate across trials, which they could use to mark target…

Children (N = 103, 4-9 years, 59 females, 84% White, c. 2019) completed visual processing, visual feature integration (color, luminance, motion), and visual search tasks. Contrast sensitivity and feature search improved with age similarly for luminance and color-defined targets. Incidental feature integration improved more with age for…