I got to speak with a high school teacher yesterday and he made an interesting remark about the use of on-screen presentations in the class room. He uses pictures and very simple visual concepts to keep the attention of the teenagers focused. The charts' main purpose is not to transfer information, they are there to keep people focused and interested.
What a different approach than most of my teachers in the 1980s: copy a page from the course book on an overhead transparency and uncover paragraph after paragraph, slowly. Or, turn your back to the class and re-write the book on the black board.
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