Using waves - waves, sound, light, electromagnetic waves; forces - forces in balance, pressure, force and motion, machines and engines; life processes - transport in living things, reproduction, responses and co-ordination, support and movement; electricity - electric charges, circuits, magnetism, electronics; our natural resources - the speed of chemical reactions, chemical calculations, fuels, energy changes in chemical reactions, metals, the chemical industry; ecology - ecosystems, populations; genetics and evolution - inheritance and genetics, evolution; teacher's notes.