'How science works' at A-level

Bill Bryson describes how his attention was grabbed at school by a cut-away diagram of the inside of the Earth. A diagram which he spotted when he first opened an unloved and grimy school science textbook. He recalls thinking, with real wonder: 'How do they know that?'. He goes on to tell of his deep disappointment when he began to read the text and found that it did not answer any of the questions that the diagram stirred in his mind. So, years later he set out to write A short history of nearly everything  by badgering scientists to tell him: 'How do you know that?', 'How did you figure it out?' and 'If you don't know, how are you going to find out?'.