This text is one of three student books which, together with teacher resource files, cover the programmes of study for co-ordinated science courses at Key Stage 4. The series builds upon the features of Physics Matters and Chemistry Counts, whilst bringing the content in line with a broad, balanced experience of science. The work is contained within manageable units, and questions and activities at the end of each chapter are used to consolidate students' understanding. Revision questions also help to stretch the more able student.