We examined the development of numerical magnitude representations of fractions and decimals from fourth to 12th grade. In Experiment 1, we assessed the rational number magnitude knowledge of 200 Chinese fourth, fifth, sixth, eighth, and 12th graders (92 girls and 108 boys) by presenting fraction and decimal magnitude comparison tasks as well as…

There is a lack of research on students' conceptions of giftedness and intelligence, despite recognition of their influence on real-life factors such as achievement and motivation. This paper presents a cross-sectional mixed methods study that investigated Finnish students' (age 6-16 years; N = 1282) implicit conceptions of giftedness and…

Scientific modeling (SM) is a core practice of science and an important component of scientific literacy. Supporting students in developing the competence to construct, use, evaluate, and revise models is hence of particular relevance. While research has shown that spatial visualization (SV), a core component of spatial ability, is correlated with…

Although the literature consistently documents strong improvements in metacognitive skills over the elementary school years, relatively little is known about the mechanisms fueling these developments. One factor that is being discussed in the literature and targeted in the present approach is cue utilization. Cue utilization quantifies the degree…

The developmental trajectory of the use of morphemes is still unclear. We investigated the emergence of morphological effects on visual word recognition in German in a large sample across the complete course of reading acquisition in elementary school. To this end, we analyzed lexical decision data on a total of 1,152 words and pseudowords from a…

Children experience good and bad days in their performance. Although this phenomenon is well-known to teachers, parents, and students it has not been investigated empirically. We examined whether children's working memory performance varies systematically from day to day and to which extent fluctuations at faster timescales (i.e., occasions,…

Modern behavior-genetic studies of twins in the United States, Australia, Scandinavia, and the United Kingdom show that genes account for most of the variance in children's reading ability by the end of the 1st year of formal reading instruction. Strong genetic influence continues across the grades, though the relevant genes vary for reading words…

The goal of the present study was to test opposing views about 4 issues concerning predictors of individual differences in Chinese written composition: (a) whether morphological awareness, syntactic processing, and working memory represent distinct and measureable constructs in Chinese or are just manifestations of general language ability; (b)…

We studied developmental trends in 5 important reasoning tasks that are critical components of the operational definition of rational thinking. The tasks measured denominator neglect, belief bias, base rate sensitivity, resistance to framing, and the tendency toward otherside thinking. In addition to age, we examined 2 other individual difference…

This nonexperimental study explored the relationships among individual differences, contextual variables, and reading achievement of English language learners (ELLs) in one large urban school district in the United States. The sample comprised 840 students in Grades 3-8 and 10 nested within 37 schools. Hierarchical linear modeling results indicate…

The trajectories of internalizing and interpersonal behaviors from kindergarten through fifth grade were studied using univariate and bivariate latent curve models. Internalizing behaviors demonstrated a small, yet statistically significant, linear increase over time, while interpersonal behaviors showed a small, yet statistically significant,…

The main hypotheses addressed in the research were (1) whether imprecision in the phonological representations of lexical items underlies the impaired expressive naming abilities of disabled readers, and (2) whether weak verbal memory might mediate the relationship between naming and reading skills. From samples of 93 first graders and 67 fourth…