Two experiments investigated the relative efficacy of two conservation training procedures and the transfer of training to another type of conservation. (SB)

Two experiments tested the assertion that development of quantitative knowledge follows a U-shaped course with an early stage of conservation based on functional significance. Tested three age groups of children from three to six years. Results suggest the assertion is unwarranted and reveal that performance in younger children is best interpreted…

A replication study was conducted to determine whether conservation-of-number performance would be improved by questioning the subject only after the transformation is performed, rather than before and after the transformation, as is done in the standard conservation test. Subjects were preschoolers, aged 0-4 to 5-7. (Author/MP)

This study assessed estimation skills on both static and transformation (conservation) tasks on numerosities ranging from 3 to 16, and included addition and subtraction trials to control for response bias. A total of 148 four- and five-year-old children estimated the number of balls of yarn sewn on elastic straps, and participated in 1 addition, 1…

Twenty children, 3-12 years old, were given a newly constructed interview on their concepts of human reproduction (social causality), in conjunction with Piaget-type tasks assessing physical conservation-identity, physical causality, and a new social identity task. The children's concepts of human reproduction appeared to proceed through a…

The child's ability to identify numerousness as a property of a set, distinct from all the other properties of that set, may be a prerequisite to conservation of numerousness of sets. To test this theory, 11 lessons designed to develop the ability to identify properties of objects and of sets of objects and to represent length and numerousness…

In order to study possible effects of the degree of perceptual illusion, 64 kindergarten children received tests of quantitative identity and quantitative equivalence for the conservations of number and continuous quantity. (SB)

Results confirm the hypothesis that identity and equivalence conservation require different mental processes. (Authors/MB)

The association of locus of cerebral hemispheric specialization of spatial function with identity and equivalence conservation judgments was tested in a group of four- to six-year-old right-handed children (N=31). (Author/MP)

This study tested 148 preschoolers between the ages of 48 and 72 months on a Piagetian number conservation task. Children's judgment accuracy, estimation, and response latency were measured. Children were also questioned about the number conservation principle. A four-step developmental sequence was hypothesized: (1) nonconservation; (2) correct…

A longitudinal study investigated children's ability to infer, from initial and final relative numerosity information, which of four transformations of a stimulus array had occurred: addition, subtraction, expansion, or contraction. It was expected that performance would reflect a sequence of three levels in understanding the effects of addition…

This study investigated the effect of different implicit definitions of equality upon children's performance on conservation tasks. In the study, traditional versions of conservation tasks are compared to modified versions in which initial equality is established through verbal counting of discontinuous quantities and measuring of continuous…

Three units of instruction were given to 20 four-year-old children and 34 five-year-old children. Unit I was designed to develop the children's ability to establish a length relation between curved lines; Unit II, to develop ability to conserve length; and Unit III, to develop ability to conserve length relations. Testing of the children occurred…