You will need: Bowl of water, plastic mug.
Many ships have been wrecked by icebergs which drift southward from the Arctic regions. Icebergs are huge, floating islands of ice which present a great threat to shipping.
Because of the relative density of ice and water, some seven-eighths of an iceberg is beneath the surface as it floats and only one-eighth can be seen above the surface. A ship can be hundreds of feet away from the visible part of an iceberg and still run against ice below the surface as shown above.
Test this for yourself by filling a plastic cup with water and freezing it solid in the refrigerator. Remove the cup and allow warm water to run over the outside for a few moments. This will loosen the block of ice and enable you to remove it.
Fill a bowl with water and float the ice in the bowl. You will quickly see how much of the ice is below the surface when your miniature iceberg is floating.
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!