The School District of Jennings, Missouri, undertook a study of the effectiveness of grouping on academic achievement in kindergarten. It was hypothesized that grouping children according to developmental lags would be beneficial to the subjects in terms of their academic and personal development; that the curricula would be partially responsible…

Fifty-four kindergarten children were screened with the Sapir Developmental Scale to highlight deficiencies in bodily schema, perceptual motor skills, and language development, and were matched in groups of three by score, chronological age, and sex with one of the three acting as control. Three first grade classes were organized as follows: one…