Beware of the pseudo method of discovery. "Pour H2SO4 on granulated zinc, and you will discover that hydrogen is given off "!Of course, Westaway, in 1929, had no idea that simulations would become popular 80 years later. As you read his words, you have to conclude that he would not have liked his students doing simulations in place of the real thing. Demonstrations may not allow students to do the experiments with their own hands, but at least they're real. With a good teacher, they can provide a good learning opportunity, provided that the class is not too large.
Beware of verification methods. "Show that ferrous ammonium sulphate contains one-seventh of its own weight of iron." This is simply asking for the evidence to be cooked.
When a boy works an experiment, keep him just enough in the dark as to the probable outcome of the experiment, just enough in the attitude of a discoverer, to leave him unprejudiced in his observations.
Do not adopt the heuristic extremist's principle that a pupil must not be permitted to take anything second hand. Life is too short.
Do not make the fatal mistake of thinking that all boys have an instinct and imagination for making discoveries, or can be made first-class workers in the laboratory. In any average science class, be satisfied with 25 per cent of α's, 50 per cent of β's, and 25 per cent of γ's, but do not stick labels on the γ's for all the world to recognize them.
Teach boys the virtue of recording all mistakes as well as successful results. Tell them that all science workers make mistakes: that that is almost the normal thing! Faraday, the most resourceful experimenter that the world has ever seen, said that he learnt far more from his mistakes than from his successes. A boy's laboratory note-book containing no mistakes is never a true record of the work he has done, and it is morally wrong to let it be presented as if it were such a record.
The pupil's notes should tell a plain tale to people who were not present when the record was made, and they should be written up in the laboratory, in ink, when the work is in progress.
In the laboratory, a teacher should have everything in readiness before a lesson is due to begin, including instructions as to the procedure to be followed in all experiments to be performed. If these instructions are given orally, they are forgotten; dictated, they take up much time; written on the blackboard, they are not permanent, and have to be written up again for a future lesson. Typed instructions answer best.
Whatever general method of teaching you adopt, do everything possible to economize time. It is bad economy — it is worse, it is sheer waste of time, to say nothing of a lack of ordinary teaching intelligence to worry beginners about, say, the difference between density and specific gravity, or " pressure at a point ", or the number of stamens in a flower.
© 2009 by Paracomp, Inc., U.S.A. www.smartscience.netFollow this author on ETC Journal.