----
Total 100

The figures in the column at the right of the table represent the
number of native born men between the ages of 21 and 45 among each
hundred native born male inhabitants engaged in the occupations
comprehended in the various groups. In the case of the industrial
group the figure is too high, as the census data relative to the
distribution of foreign and native born include all ages, and there is
a smaller proportion of American born adult men employed in industry
than is found in the lower age groups. Extensive computations have
shown, however, that the inaccuracies due to this cause are not
serious enough to affect the use of the figures for our purpose.

Let us now consider what these proportions mean in establishing
vocational courses to prepare boys for wage-earning pursuits. The
future expectations of the boys in a large elementary school enrolling
say 1,000 pupils of both sexes would be about as follows:

_Number of boys who will enter_
Manufacturing and mechanical occupations 220
Commercial occupations 100
Clerical occupations 80
Transportation occupations 55
Domestic and personal service occupations 25
Professional occupations 15
Public service occupations 5
----
Total 500

This distribution includes all pupils, from the beginners in the first
grade to the older boys in the seventh and eighth grades. It is
certain, however, that differentiated instruction for vocational
purposes is not possible or advisable for the younger children.
According to the commonly accepted view among educators, vocational
training should not be undertaken before the age of 12 years, and many
believe that this is too early. In an elementary school of 1,000
pupils there would be about 80 boys 12 years old and over. Applying
to this number the ratios given in the previous table we obtain the
following:

_Number of boys who will enter_
Manufacturing and mechanical occupations 35
Commercial occupations 16
Clerical occupations 13
Transportati