The Importance of blackboards in a school are given below:
Blackboard is the commonest and the most important of all visual aids. It is very difficult to imagine a classroom without a blackboard. It is, in fact, such a commonplace of classroom teaching that it is rarely used as effectively as it should be.
It plays a very important role in making the instructional process effective. It is difficult to imagine a blackboard which is too big. A blackboard 8 to 12 feet long and 3 feet in height is satisfactory.
The bottom edge of the blackboard should be 3 feet above the floor on which the teacher stands.
There are many varieties of a blackboard:
(a) The Wall Blackboard:
This is the most widely used and economical type of blackboard. It does not use any space in a classroom as it is mounted on a wall facing the students. It is useful for writing, solving mathematical problems as well as drawing figures.
However, its main disadvantage is that it is immovable. It should be painted in black every year so as to maintain the quality of its service. It should ideally be used as a supporting arrangement rather than the main one.
(b) The Roll-up Blackboard:
It is usually hung on the wall or on a stand and its uses are the same as a wall blackboard. However, its advantage is that it can be moved from one place to another.
Besides, a teacher can write teaching-learning material and prepare a roll-up board in advance before coming to class. This saves his/her time and enhances his/her teaching effectiveness. This is also useful in securing students’ attentiveness to classroom procedures.
(c) The Easel Blackboard:
This is one of the best varieties of a blackboard consisting of an easel and a separate board. It is easily movable from one part of a classroom to another. Both the sides of such a board can be used and it is possible to conceal one side by turning the board.
(d) The Sliding Blackboard:
Some of the better equipped schools have this type of board. It has two purposes: (i) When the teacher wants to keep some material on the blackboard for a relatively longer time, and (ii) When some content-matter is to be concealed at the time of examination from students; this type of board is used.
Such a board can also be moved up or down as and when required. It is an improvisation over the wall-black-board but is more expensive. However, just like a wall blackboard, it is immovable.
(e) Green Board:
This is, as the name suggests, green in color, easy to use and maintain, made of glass and more commonly used type of board these days.
(f) Multi-Purpose Board:
In this type of board, there is a black or a green board covered by two other openable doors. The outer side of these doors can consist of a flannel board and a board with lines for graphs. Besides, there is also an arrangement for a rolled-up screen for over-head projector.