How to 'Kill' a Potato
You will need: Two potatoes, knife, sugar, dish of water.
Take two potatoes of roughly equal size and 'kill' one of them by boiling it for 20 minutes. Now slice the top and bottom off both potatoes and scoop a hollow in each. Then remove a complete circle of peel from the lower half of each potato (Fig. 1).
Place a spoonful of granulated sugar in the cavity of each potato. Fill a dish with water and stand the two potatoes in the water.
Leave the potatoes 24 hours. At the end of this time the cavity in the raw potato will be full of water and sugar, but the sugar in the cooked potato will be undisturbed.
This drawing up of water by the living cells of a plant is called 'osmosis.' By cooking the second potato we 'killed' the cells and thus prevented osmosis from taking place.
Children learn best through doing
Before children can understand a thing, they need experience: seeing, touching, hearing, tasting, smelling; choosing, arranging, putting things together, taking things apart. Experimenting with real things.
Old-time school teaching used only words and the teachers thought children knew something if they could repeat it. Now we know better. To reach practical understanding we do not need to use many words with young children.
Children are clever. They learn a lot, without being taught. The greatest skill - to be able to talk, to communicate is learnt outside school. In the classroom it's the children who need to talk the most. Unfortunately it is the teacher who does most of the talking!