What is matter?
Everything around us is a physical body. Bodies are natural (stone, tree, cloud) or artificial (table, pencil, car); natural ones may be living or non-living. What a body is made of is called a substance: a spoon (body) is made of steel, a table (body) of wood. Substances are organic (obtained from living things: wood, milk, fat, honey, amber) or inorganic (salt, chalk, iron, glass). Substances are also pure (a single substance: gold, diamond, graphite) or mixtures (several substances together: milk, air, soil). All matter is made of tiny particles. In a solid the particles are packed close together and the body keeps its shape; in a liquid they move about and take the shape of the container; in a gas they are far apart and fill all the space. When heated, particles gain energy and move faster: ice melts at 0°C and water boils and turns to vapour at 100°C.
“Body and substance”: take ten cards with objects and write a “body — substance” pair for each (for example glass cup: cup — glass). Dissolve salt in water and watch the salt remain when the water evaporates (an adult does any heating).