Anyone who has had any time to spend at a railroad station has found himself sooner or later on the penny scales comparing his weight and height at sixteen or twelve with the standard given. When the comparison does not turn out to his satisfaction he decides that the average given cannot be accurate, and in the past his conclusion has been correct. It is with the aim of determining these standards more exactly that the Graduate School of Education has undertaken in Dean Holmes' words a "research enterprise of major importance".

The data heretofore on the mental and physical growth of children at best has been incomplete because it has been based on measurements made from various "average" groups representing various stages of development. The result has been a flat, one-sided picture. The investigation of the School of Education, involving the careful measuring and testing of hundreds of children over a period of twelve years, will fill in the gaps in the information already at hand and, by following the same groups all the way through, obtain for the first time accurate knowledge of the growth of individuals.

The work, once accomplished will be invaluable. To say that it is one of the most elaborate experiments in the science of measurement is a conservative judgment. It will give teachers, psychologists, and physicians an accurate record of individual development properly correlated with the development of a group, and both over a long period of time. The experiment of the School of Education will make possible for the first time what may be called a three-dimensional knowledge of children's growth.