Discrepancies among family members' ratings on aspects of family functioning are challenging both, methodological and interpretational. Family members' perspectives and their discrepancies are indicators of family functioning, affecting adolescents' psychological development. Previous research focused on linear effects, ignoring that rather…

Mathematical arguments are central components of mathematics and play a role in certain types of modelling of potential mathematical giftedness. However, particular characteristics of arguments are interpreted differently in the context of mathematical giftedness. Some models of giftedness see no connection, whereas other models consider the…

For many decades, the amount of geometry curriculum worldwide has been cut, mathematics curricula have lacked diversity of geometrical phenomena, and geometry teaching has been reduced to a somewhat eclectic mix of activities. Recently, new trends have begun to counteract these tendencies by framing new curricula around fundamental ideas. The…

This study is a substantive-methodological synergy in which exploratory structural equation modeling is applied to investigate the factor structure of multidimensional self-concept instruments. On the basis of a sample of German students (N = 1958) who completed the Self-Description Questionnaire I and the Self-Perception Profile for Children, the…

Currently, language competences in mathematics lessons gain more attention in Germany. The paper reports an interdisciplinary study of linguistics and mathematics education on reasoning. A model to rate the competences in arithmetic reasoning at primary level will be presented for discussion: mathematical reasoning is coded separately from its…

This study tested whether the gender intensification hypothesis applies to relations between multiple domain-specific self-concept facets and self-esteem. This hypothesis predicts gender-stereotypic differences in these relations and assumes they intensify with age. Furthermore, knowledge about gender-related or age-related differences in…

Researchers have used various theories to explain deaf individuals' reading skills, including the dual route reading theory, the orthographic depth theory, and the early language access theory. This study tested 4 groups of children--hearing with dyslexia, hearing without dyslexia, deaf early signers, and deaf late signers (N = 857)--from 4…

This study aims to develop a short German version of the Self Description Questionnaire (SDQ I-GS) in order to present a robust economical instrument for measuring German preadolescents' multidimensional self-concept. A full German version of the SDQ I (SDQ I-G) that maintained the original structure and thus length of the English original SDQ I…

This study addresses the development of health-related behavior during childhood and adolescence and the protective influence of an authoritative parenting style. The study is based on two samples followed from Grades 2 through 5 and from Grades 4 through 7. The first sample consisted of 432 second graders with a mean age of 7.9 years at the…