Besides being larger than previous schools, it included large windows to light the interior effectively.
The rear of the blocks also included large round windows.
Since the early 2000s, some cases have included clear side panels or acrylic windows so that users can look inside while it is operating.
They have been modified to include large windows in the back, rails and handles.
The walls are made of vinyl, canvas or a similar material and include windows with screens.
The lower story which was constructed of stone, included handsome arched windows.
Other specialty models include windows that close automatically when it rains.
Other characteristics elements included large decorated windows and small towers.
The boxes were also more colourful and included clear windows so the contents could be seen.
The physical components of the envelope include the foundation, roof, walls, doors and windows.