This practical book answers common questions about materials by looking at evidence and demonstrating their properties through a range of carefully chosen experiments that can be done in the classroom or at home. It covers such questions as 'What are states of matter?', 'How does heat get through materials?', 'What happens when a solid dissolves?' and 'What are chemical changes?' It also includes questions for readers to investigate further on their own. Written by a highly experienced and acclaimed science writer, the book includes links to useful websites as well as glossary, index and list of further reading.