Place value concepts were measured longitudinally from kindergarten (2017) to first grade (2018) in a diverse sample (n = 279; M[subscript age] = 5.76 years, SD = 0.55; 135 females; 41% Black, 38% White, 8% Asian, 12% Latino). Children completed three syntactic tasks that required an explicit understanding of base-10 symbols and three approximate…

This study examined the generality of the logarithmic to linear transition in children's representations of numerical magnitudes and the role of subjective categorization of numbers in the acquisition of more advanced understanding. Experiment 1 (49 girls and 41 boys, ages 5-8 years) suggested parallel transitions from kindergarten to second grade…

The development of the ability to associate numerals with sets of appropriate size was studied in children, ages 4 to 5-1/2. (ST)

Two studies trace children's acquisition of counting as a means to extract, compare, and reproduce number from arrays of objects. Study 1 examined 3-, 4-, and 7-year-olds' use of counting to compare and reproduce arrays numerically. In study 2, nine of the 3-year-olds from the study 1 were retested after 12 and 18 months. (Author/JMB)

In a replication study, children 3 and 4 years old were given verbal rule training in order to probe the importance of identity, reversibility, and compensation explanations in training number and length concepts. Among the results, as before, identity was found to be the most significant factor in conservation acquisition. (Author/RH)

Study tests four predictions derived from Piaget's cognitive theory. (CB)

A combination of readiness and body-part training was the most effective in producing number conservation with external objects. (Authors)

Results are discussed in terms of why children of the same age fail to conserve number in the standard conservation task and how complex number concepts might develop. (Author)

Two studies sought to determine the developmental relationship between the child's use of counting as a notational symbol system to extract, compare, and reproduce numerical information and the development of number conservation. Subjects were four- to six-year-old children in Study 1 and seven- to nine-year-old learning disabled children in Study…

Judgments of similarities between numbers were solicited from kindergarten, third-grade, sixth-grade, and adult subjects. Results suggested children become sensitive to an expanding set of numerical relations during the period from kindergarten through sixth grade. Results of a second study suggested that the number similarity judgments of…