The Relationship between Variability in Physical Growth and Academic Achievement Among Third- and Fifth-Grade Children

Abstract

MUCH RESEARCH has been carried on during thepast four decades to determine the relationship between various measures of physical growth and measures of intelligence and of academic achievement. This research has shown rather consistent low positive correlations between measures of physical growth and of mental age or intelligence. These results have been interpreted quite differently by various writers, as represented in Paterson and Olson. Paterson maintains that since childhood is a period of growth, positive corre lations are to be expected but are not evidence of an underlying unity of growth (2). Olson writes that there is an underlying unity of growth which manifests itself in the various aspects of growth, mental as well as physical, and that children tend to grow at a uniform rate in all areas. Olson's concept of organ ismicage is an attempt to ascertain an individual's center of growth gravity. Also, he suggests that a pattern of growth which is inconsistent or variable ; i. e. , high in some measures, medium in others, and low in still others, may reflect an underlying disturbance of the organism that may influence academic achievement in either of two ways: similar variability in achievement or lower achievement (1). The present research was designed to test two hypotheses related to Olson's ideas: (1) variability in physical growth is accompanied by variability in academic achievement, (2) variability in physical growth is accompanied by low academic achievement. Variability was defined as an index of irregularity infive physical measures: height, weight, strength of grip, dentition, carpal development; or in three achievement measures: reading, arithmetic, and language. Subsequently, dentition was dropped from the physical variability index for reasons to be re ported later. Subjects The subjects were 54 third-grade and 66 fifth-grade children enrolled in four classrooms of two elementary schools. The children's mean chronological age was near the mean of carpal and dental age but well below the mean age of height, weight, strength, mental, and achievement in reading, arithmetic, and language. Seventy-five per cent of the children's fathers were in the profession