A school offers a much better opportunity than any clinic for the study of normal children. It is more feasible to follow a given group of school children over a number of years than the same number of children in a clinic, and it is much easier to determine abnormal circulatory behavior in a school child under standard conditions than in the environment of a clinic. Especially is this true of a private school of the so-called "experimental" type where great opportunity is given to observe children in a natural environment. For this reason, the Bureau of Educational Experiments has conducted a series of studies on growth in children in the City and Country School of New York City. As physician to the Bureau, I had the opportunity of acting as physician in this school from 1919 to 1926 when the records used for these studies were being collected. At