As a matter of fact, the traditional blackboard and chalk crayons cannot hold a candle against the hi-tech teaching aid projectors or even white-board and erasable marker pens for that matter. Modern teaching aids like the ones mentioned does have their own flaws as well as plus points.
Projectors and powerpoint presentations are superior in a sense that, they make demonstrations and giving notes much easier - as easy as clicking the mouse, literally. With their introduction in the classrooms, the strenuous task of scribbling on the blackboard has been done away. To cite an example, during my schooldays, I've observed some of my teachers resorting to give us notes through oral dictation instead of straining their eyes and arms on the blackboard. Modern classroom equipment renovation has done away with this. This saves a lot of time as well as conserves the energy of the teacher. Use of blackboard and chalk crayons, in addition also pose a threat to the respiratory complications. Although chalks are regarded as non-toxic, the runaway particles while wiping them off the blackboard can accumulate in our respiratory tracts and prove harmful or even to the point of being lethal in some cases. The upgraded apparatuses has made our classrooms safer and cleaner. Even the teachers need not bother about leaving the school with chalk dust on their clothes.
The de-merits of modern classroom equipments, foremost of all, is that, they are expensive. Not every school can have the budget to procure these. This case is prevalent in the rural areas. Although, both urban and rural schools study the same syllabus, the rural counterpart cannot be expected to keep pace with the urban institutions. This results in disparity.
They get inconvenient and cumbersome considering the fact that, in order to give a hassle free lecture the next day, the teacher needs to do a 'hard' homework at home. In addition to preparing the teaching materials, he/she is required digitize it. A prior powerpoint or flash presentation needs to be prepared. This means more than a working knowledge of computers is demanded from the teacher. Another, wet-blanket area of modern equipments is the fact that, they are as good as the classroom's dust-bin contents in the absence of proper power supply. They are resource consuming and demands frequent tweakings and maintenance jobs to keep them in working conditions. In the case of white boards, the only drawback is that the strenuous exercise of painstakingly scribbling on the board and wiping them off afterwards is still present (and very much required).
But at the end of the day, as stated above, the most preferred mode of imparting knowledge as far as equipments and props are concerned, are those modern amenities. To sum up, modern projectors and white boards are to the traditional blackboard in the way modern SUVs are to the General Purpose Vehicle (JEEP).
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