Tool making evidences intelligent, flexible thinking. In Experiment 1, we confirmed that 4- to 7-year-olds chose a hook tool to retrieve a bucket from a tube. In Experiment 2, 3- to 5-year-olds consistently failed to innovate a simple hook tool. Eight-year-olds performed at mature levels. In contrast, making a tool following demonstration was easy…

In two experiments, we investigated whether 4- to 5-year-old children's ability to demonstrate their understanding of aspectuality was influenced by how the test question was phrased. In Experiment 1, 60 children chose whether to look or feel to gain information about a hidden object (identifiable by sight or touch). Test questions referred either…

Few studies have explored the development of response selection processes in children in the case of object manipulation. In the current research, we studied the "end-state comfort effect," the tendency to ensure a comfortable position at the end rather than at the beginning of simple object manipulation tasks. We used two versions of the…

Four experiments examined children's inferences about the relation between objects' internal parts and their causal properties. In Experiment 1, 4-year-olds recognized that objects with different internal parts had different causal properties, and those causal properties transferred if the internal part moved to another object. In Experiment 2,…

Discussed are results of studies of the cognitive development of 2- and 3-year-old children which suggest that the mind makes gains in the ability to think as gains in language development are made. "Thinking" in this context refers to the judgments children made as they selected objects and maneuvered them into one arrangement or…

Two experiments used object-manipulation tasks to examine whether one- to two-year-olds form superordinate-like categories by attending to object parts. Findings indicated that 14- and 18-month-olds behaved systematically toward categories with different, but not matching, parts. Without part differences, none formed superordinate categories.…

Depending on age and the demands of the task, people may use different processing strategies in object categorization. Three-year-olds used a wholistic approach with strong effects of object typicality on three categorization tasks. Older children and adults showed differential effects of typicality, suggesting various strategies including…