Previous research on Montessori preschool education is inconsistent and prone to analytic flexibility. In this preregistered study, disadvantaged preschoolers in a French public school were randomly assigned to either conventional or Montessori classrooms, with the latter being adapted to French public education. Adaptations included fewer…

Longitudinal tracking of 107 three- to-thirteen-year-olds in a cross-sequential design showed a 6-step theory of mind (ToM) sequence identified by a few past cross-sectional studies validly depicted longitudinal ToM development from early to middle childhood for typically developing (TD) children and those with ToM delays owing to deafness or…

Although theory of mind (ToM) is argued to emerge between 3 and 5 years of age, data from non-Western, small-scale societies suggest diversity. Deeper investigations into these settings are warranted. In the current study, over 400 Melanesian children from Vanuatu (range = 3-14 years), growing up in either urban or rural remote environments,…

This meta-analysis summarizes 113 research reports worldwide (121 cross-sectional and 7 longitudinal studies) on age differences in ethnic, racial, or national prejudice among children and adolescents. Overall, results indicated a peak in prejudice in middle childhood (5-7 years) followed by a slight decrease until late childhood (8-10 years). In…

Consecutive retestings of 92 U.S. preschoolers (n = 30), Chinese preschoolers (n = 31), and deaf children (n = 31) examined whether the sequences of development apparent in cross-sectional results with a theory-of-mind scale also appeared in longitudinal assessment. Longitudinal data confirmed that theory-of-mind progressions apparent in…

To bridge the social-reasoning focus of developmental research on irony understanding and the pragmatic focus of research with adult populations, this cross-sectional study examines 5-, 7-, and 9-year-olds' (n = 72) developing understanding of both social-cognitive and social-communicative aspects of discourse irony, when compared with adults (n =…

Relations were examined between children's sleep and their externalizing and internalizing symptoms. Longitudinal relations were examined when children were in 3rd (T1) and 5th (T2) grades, and cross-sectional relations were assessed at T2. Participants included 176 children at T1 (M = 8.68 years) and 141 children at T2 (M = 10.70 years). Sleep…

Studies using the English and Spanish MacArthur Communicative Development Inventories demonstrated that the grammatical abilities of 20--30-month-old bilingual children were related more strongly to same-language vocabulary development than to broader lexical-conceptual development or maturation. First, proportions of different word types in each…

Three studies (N=144) investigated how toddlers aged 18 and 24 months pass the surprise-mark test of self-recognition. In Study 1, toddlers were surreptitiously marked in successive conditions on their legs and faces with stickers visible only in a mirror. Rates of sticker touching did not differ significantly between conditions. In Study 2,…

A core task in language acquisition is mapping words onto objects, actions, and events. Two studies investigated how children learn to map novel labels onto novel objects. Study 1 investigated whether 10-month-olds use both perceptual and social cues to learn a word. Study 2, a control study, tested whether infants paired the label with a…

Maintains that multiple case study developmental pathway research is needed to substantiate the theoretical propositions of Rothbaum et al. (Author/KB)

Proposes that conceptual change is constrained by the child's conceptual structures and the structures inherent in problem-solving tasks. Uses a microgenetic case study and group data to examine how interaction between strategies children bring to a task and the detailed task structure redirect children's attention and create the possibility of…

Paper presented at the meeting of the American Psychological Association, Miami, Florida, September, 1970. (RY)