Examines the issue of object sorting in early infancy. Forty-eight infants at 6, 9, and 12 months were presented with eight sets of small, manipulable objects. At six months, selective manipulation was absent; at nine months, 94 percent of the infants sequentially touched similar objects and at 12 months 100 percent did so. (Author/DB)

Matrix tasks to assess multiple classifications and multiple seriation skills were administered to 160 children (40 Ss each from preschool, kindergarten, first and second grade levels). Each child received six matrix subtasks (reproduction and transportation of cross classification I, double seriation, and cross classification II) in one of six…

This study examines the development of children's understanding of temporal cycles and the relationship between cyclic concepts and cognitive development. A sample of 62 children, ranging in age from 4 to 10 years, were administered Piagetian tests of classification and seriation and a variety of specially designed cyclic tasks. (Author/JMB)

Two experiments which investigated the young child's ability to deal with multiplicative classes and relations (considered behavioral indices of concrete operations thought) in double series and cross class matrices are described and discussed. In the initial study, 160 children from preschool through grade 2 received six matrix subtasks…

The purposes of this study were to: (1) determine the influence of a series of experiences involving the equivalence relation "same length as" and the asymmetric transitive relations "longer than" and "shorter than" on the ability of first and second grade children to classify and seriate objects on the basis of length; (2) investigate the…