Two 9-year-old boys are described who performed in the normal range on measures of IQ, language ability, and reading. The boys were unable, however, to acquire elementary numerical skills and also manifested other specific cognitive deficits associated with the Gerstmann syndrome. (Author)

A longitudinal investigation on development of conservation skills in 31 learning disabled (LD) children suggested that delayed transition between preoperational and concrete operational thought may be an important factor in understanding the continued school failure of learning disabled children. (Author/CL)

Discusses the development of informal mathematics in young children, the problems with formal mathematics instruction, how the traditional approach fails to address mathematics learning disabilities, and how a developmental perspective can assist in the identification and treatment of students with mathematics learning disabilities. (CR)