The main requirements to be considered in planning are the number of boys and girls for whom provision is necessary, while the distribution of scholars in respect of age has also an important bearing on organisation. The type of building will probably depend to some extent on the manner in which the Local Education Authority have acted in excluding children under five years of age. The nature of accommodation required in upper departments of ordinary schools will be affected if higher elementary schools are already provided in the locality.

A head teacher can seldom effectively undertake responsibility for more than four to five hundred scholars, in addition to the staff required for that number. This is therefore the greatest number for whom provision can wisely be made in one department. Each department must have its own head teacher, responsible for general control, supervision, instruction, and discipline.

The number of departments on any site will depend on the total number that provision is required for. It will seldom be that more than three departments (or four, if one be for boys and girls of from seven to nine or ten years of age) could properly occupy parts of the same building. When a school with separate departments for boys, girls, and infants is attended by all children of the area for which it is available, it is not unusual to find the average attendance in each department much the same. It is desirable to have a certain margin of places in the infants department to meet greater variability of attendance at different seasons. These considerations should be kept in mind in deciding how many places shall be provided in the several departments of a large school ; in every case local circumstances must be carefully considered.

The number and circumstances of the scholars attending each department, and the number and qualifications of the staff employed in each, determines approximately the grouping of scholars, the number of rooms to be provided, and the places in each. Rooms must be grouped compactly and conveniently to secure proper organisation and supervision. Every public elementary school must be planned so that children who attend can be seated in the best manner. The places provided in any room depends not only on area, but also on lighting, shape of room (especially in relation to kinds of desk proposed), and position of doors and fireplaces, which should be so arranged as to allow the whole of one side to be left free for groups of desks.

For large departments containing from 350 to 500 places the most suitable plan is that of a central hall with rooms grouped round it. Such a department would require seven to ten classrooms.

Smaller departments may be conveniently planned with classrooms opening from a corridor, and this arrangement may even be adopted for larger departments. For small schools a schoolroom with one or two or more classrooms is sufficient. There should be at least one classroom.

Where a site is sufficiently large and open, the most economical and preferable plan is to have all rooms on the ground floor. It is desirable in any case that a school should not be more than two floors in height. A three-floor building is open to many objections, though necessary in special circumstances ; for example, where land is costly, or where it is otherwise impossible to obtain adequate area for playgrounds.