Recent literature on the acquisition of "more" and "less" is reviewed with special emphasis on some key issues. The overriding goal of studies in this area has been the discovery of the developmental sequence that the child follows in acquiring "more" and "less," and, more generally, all comparative structures. The earliest empirical studies on…

Six groups of nursery schoolers, kindergarteners, and first graders balanced for sex were trained and tested on a series of discrimination learning and transposition problems. (Author)

Nonsense forms with nonsense labels were utilized in a match to sample task to observe whether children's word extensions are based on static form characteristics or on functional action characteristics. The stimuli consisted of: (1) a single model object which performed an action; (2) a selection array consisting of one object similar in form to…

Piaget's model of children's conceptual learning and development was compared with Klausmeier's Conceptual Learning and Development (CLD) model in a longitudinal study. The CLD model suggests four successive levels of concept learning: (1) concrete--recognizing an object which has been encountered previously; (2) identity--recognizing a known…