men are employed. With respect to their future occupations the 35 boys
in the industrial group are likely to be distributed about as follows:

_Number of boys who will enter_
Metal trades 8
Building trades 7
Printing trades 1
Other trades 2
Semi-skilled and unskilled industrial occupations 17
---
35

The analysis can be carried still further, for these trade groups are
by no means homogeneous. The building trades, for example, include
over 20 distinct trades, a number of which have little in common with
the others as to methods of work and technical content.


ORGANIZATION AND COSTS

At this point it becomes necessary to take cognizance of certain
administrative factors which have a marked bearing on the problem.
They relate to the organization of classes in elementary schools and
the cost of teaching. In a school of 1,000 pupils there would be at
least five separate classes for the seventh and eighth grades. The 35
boys who need industrial training are not all found in a single class,
but are distributed more or less evenly throughout the five
classrooms, that is, there are approximately seven in each class. A
differentiated course under these conditions is difficult if not
impossible. In a few of the Cleveland elementary schools the