This article examines working memory functioning in children with specific developmental disorders of scholastic skills as defined by ICD-10. Ninety-seven second to fourth graders with a minimum IQ of 80 are compared using a 2 x 2 factorial (dyscalculia vs. no dyscalculia; dyslexia vs. no dyslexia) design. An extensive test battery assesses the three subcomponents of working memory described by Baddeley (1986): phonological loop, visual-spatial sketchpad, and central executive. Children with dyscalculia show deficits in visual-spatial memory; children with dyslexia show deficits in phonological and central executive functioning. When controlling for the influence of the phonological loop on the performance of the central executive, however, the effect is no longer significant. Although children with both reading and arithmetic disorders are consistently outperformed by all other groups, there is no significant interaction between the factors dyscalculia and dyslexia.

Similar patterns of results emerged for both subgroups of children with intellectual disability, indicating that problems with phonological information processing seem to be one of the causes of cognitive impairment in individuals with intellectual disability.

According to Klahr's (2000, 2005; Klahr & Dunbar, 1988) Scientific Discovery as Dual Search model, inquiry processes require three cognitive components: hypothesis generation, experimentation, and evidence evaluation. The aim of the present study was to investigate (a) when the ability to evaluate perfect covariation, imperfect covariation, and non-covariation evidence emerges, (b) when experimentation emerges, (c) when hypothesis generation skills emerge, and (d), whether these abilities develop synchronously during childhood. We administered three scientific reasoning tasks referring to the three components to 223 children of five age groups (from age 4.0 to 13.5 years). Our results show that the three cognitive components of domain-general scientific reasoning emerge asynchronously. The development of domain-general scientific reasoning begins with the ability to handle unambiguous data, progresses to the interpretation of ambiguous data, and leads to a flexible adaptation of hypotheses according to the sufficiency of evidence. When children understand the relation between the level of ambiguity of evidence and the level of confidence in hypotheses, the ability to differentiate conclusive from inconclusive experiments accompanies this development. Implications of these results for designing science education concepts for young children are briefly discussed.

These findings do not support the notion of different cognitive functioning because of differences in intelligence of these two groups. In the ongoing discussion about the role of intelligence (especially as to the postulated discrepancy between intelligence and school achievement in diagnosis and special education), our findings might lead to rethinking the current practice of treating these two groups as fundamentally different.

A systematic review was conducted to gain a more nuanced understanding of similarities and distinctions across countries in the development of executive functions (EF). The review includes 26 studies, with child and adolescent participants, that were published between 2006 and 2018. Both similarities and differences within developmental patterns of EF are identified across different countries. Across countries, bilingual children are shown to outperform their monolingual peers. Task improvement with age is not consistently reported in all studies, with no linear effects apparent in children from developing countries or regions. Gender differences on EF measures also vary between countries. Girls perform better than boys on EF tasks and parent and teacher ratings of EF in both Western and East Asian samples. Yet, in Iran and Tanzania, boys receive higher EF scores. From preschool age through adolescence, East Asians outperform Western counterparts on direct assessment measures of EF. However, strong discrepancies can be found between measures of direct EF assessment and parent and teacher ratings of children's EF. Chinese parents rate their children's EF as lower compared with parents from other countries. The role of contextual factors explaining differences in EF development is discussed. Highlights This paper presents the first systematic review on the topic of cross‐national variation in children's EF development. A clearly defined conceptual framework regarding EF facets and analysis of a wide age span underpin this review. From preschool age through adolescence, East‐Asian children outperform their Western counterparts on direct assessment measures of EF.