The main purpose of this research was to determine three- to six-year-old pre-schoolers' recognition of basic geometric shapes, the criteria they use to distinguish members of a shape class and whether or not those criteria change in relation to age. Participants were 100 children aged three to six. Data were gathered from individual interviews…

Three experiments explored effects of stimulus and task factors on tendency to categorize according to taxonomic relations when those relations conflict with appearances. When provided with information that constrained categorization, preschoolers and adults reliably based their decisions on taxonomic relations between physically dissimilar items.…

Three experiments examined how flexibly two- to four-year-old children use the words "big" and "little" in normative, perceptual, and functional contexts. Results showed that children switched easily from a normative context but made errors when asked to switch to a normative context. (MDM)

In three experiments, three normal preschoolers were presented with sorting tasks ordinarily insoluble for four-year-olds. Found that, although the subjects had difficulty correctly sorting the pictures when told what criterion to sort by, they could provide correct answers when asked what they were looking for. This self-instructional effect was…