In several papers Palmer (1,2,3,4) reported the results of investigations on the growth of the white elementary school children of Hagerstown, Naryland, dealing especially with the variations in the weight of the children aged 6 to 11 years during the period 1921-1927 and during some of the years (1933-1934) of the economic depression. Annual observations on the growth, particularly in weight, of the Hagerstown children have been continued by the U. S. Public Health Service so that it is possible to report on the weight of children for the years following 1933 and thus to extend the findings of Palmer. At the same time, in this and in the following series of reports it is hoped that by the comparisons of the results obtained on children of the same ages in different calendar years and on children of different age groups in the same calendar year to arrive at a better understanding of the pattern of growth characteristics of white school children. The study of growth may be approached in three different ways. First, the results of the measurements may be given for children of the same age at different calendar years. By this method striking environmental influences upon growth may be discovered as, for instance, those that affected children of Central Europe after a short period of especially deficient nutrition during and immediately subsequent to the last World War (5). In addition, the existence of a tendency to increase in size, as has been demonstrated in many parts of the world, can also be described by such comparative measurements when they cover a long succession of years. Second, the results may be obtained for children of the same generation at successive years of age. This would be the case if we were able to pursue a school generation, let us say, from 6 years of age in 1930 throughout the whole school life until the age of 16 years in 1940. The characteristics of the pattern of growth of the same generations could thus be described when it is assumed that the hereditary and environmental factors for the group as a whole have been almost constant and provided that the number of children does not greatly diminish or change throughout the years of observation (6,7). We could call the resulting pattern the average individual or longitudinal growth curve for the specified generation (e.g., school generation 1930, 6 years of age or, correspondingly, birth generation 1923-24) and compare it from many points of view with other generations, former or later ones of the same