During communication, conversational partners should offer as much information as is required and relevant. For instance, the statement "Some Xs Y" is infelicitous if one knows that all Xs Y. Do children understand the link between speaker knowledge and utterance strength? In Experiment 1, 5-year-olds (N = 32) but not 4-year-olds…

Preschool children (N = 104) read a book that described and illustrated color camouflage in animals (frogs and lizards). Children were then asked to indicate and explain which of 2 novel animals would be more likely to fall prey to a predatory bird. In Experiment 1, 3- and 4-year-olds were tested with pictures depicting animals in camouflage and…

Examined two- to four-year-olds' and adults' internalized representations of the sizes of buttons, plates, and shoes in five experiments. Results suggested that three- and four-year-olds had accurate knowledge of the typical sizes of buttons and plates. Two-year-olds demonstrated accurate internal representations of the sizes of shoes. (RJC)

Two studies with 3-, 4-, and 5-year-olds examined whether young children can differentiate expertise in the minds of others. Findings indicated that all children could correctly attribute observable knowledge to familiar experts, such as a car mechanic. Preschoolers had difficulty making attribution of knowledge of scientific principles to…

Three experiments examined 3- to 5-year olds' understanding of the intended nature of pretend behavior. Found that 4-year olds understood intention as a mental cause of action and construed pretend behaviors mentalistically, but systematically associated ignorance of a specific animal with pretending to be that animal. Concludes that Lillard's…

Five experiments tested whether children understand pretense intentions before they understand pretense mental representations. Findings revealed that children did not understand that intention is crucial to pretense. Various methodological factors that might have compromised results such as force choice versus yes-no questions or using a…

Maintains that Lillard's and Joseph's articles provide an example of how apparently divergent empirical results may turn out to reflect interesting differences between children and adults. The researchers agreed that for young children, pretense is often, but not necessarily, intentional and neither found evidence for a representational…

Examined in 4 experiments 2-year-olds' knowledge of solidity in search tasks. Found no evidence that 2-year-olds represented solidity and support constraints on trajectories of falling objects; two experiments included 2.5-year-olds who succeeded on search tasks. Explored implications of 2-year-olds' poor performance in light of very young…

Four studies explored children's ability to differentiate future distances of events. Findings indicated that 4-year-olds failed to differentiate future distances. Five-year-olds could distinguish events occurring in coming weeks/months from those many months away. Six- through 8-year-olds made more differentiated judgments than younger children…

Studied the ages at which 240 children in grades one to five read and transformed times given in analog and digital displays, linked times to activities, and judged the order of hours in the day. Findings indicated that digital time reading was well developed by the first grade. (RJC)

Two studies addressed whether preschoolers consider speakers' knowledge states when establishing initial word-referent links. Children showed better learning from a speaker knowledgeable of novel words' referents than from an ignorant speaker. Four-year-olds, but not 3-year-olds, learned words better when speaker said the object was made by…

Tested role of event plausibility and script-relevant knowledge in events suggestively planted in memory of 5- to 7-year olds and 9- to 12-year olds. Found that the majority did not remember either false event. Significantly more children recalled the plausible but not the implausible false event; only one recalled the implausible but not…

A series of six experiments compares young children's competence in attributing absence of knowledge (ignorance) to their competence in attributing a false belief to the other. (HOD)

Two experiments examined development of economic understanding among 5-, 7- and 9-year-olds. Found that most 5-year-olds understood the goal of acquiring desired goods, and most 7- and 9-year-olds also understood the goals of seeking profits, acquiring goods inexpensively, and competing successfully with other sellers. Results suggest that older…

Six match-to-sample picture/object selection experiments explored 3- to 5-year-olds' knowledge about superordinate words and acquisition of this knowledge. Findings indicated that number of standards (one versus two), types of standards (different versus same basic-level categories), and nature of representation (pictures versus objects)…