A promising line of inquiry concerning the development and use of formal operations strategies is presented and a number of conceptual and empirical questions are raised. (Author/PN)

Using a microcomputer "dart" game, this study of 61 primary school students investigated how children of different ages used counting to make numerical estimates. Results showed developmental differences in accuracy of estimation, fluency in counting and sophistication of self-reported strategy use. (BS)

Primary school children at different stages of acquisition of conservation pretended that their judgments on a series of conservation problems were the opposite of their actual beliefs. The nonconservers and transitional conservers made significant gains in conservation, while the conservers did not regress. Cognitive dissonance training is…

Four-year-old (N=45) children were trained for eight weeks in one of three conditions: (1) logical foundations (classification and seriation); (2) number skills (counting); and (3) control. The experimental treatments were based on the logical foundations model of Piagetian theorists and a skill integration model. (Author/BS)

Performance of over 200 third and fourth graders on a post test and a two-month follow-up measure showed that groups receiving lessons based on a task analysis instructional design performed significantly better than groups receiving placebo lessons at two levels of advanced mastery for the concepts, "equilateral triangle" and…