- Complete Key for Schools is official preparation for the Cambridge English: Key (KET) for Schools exam. It combines the very best in contemporary classroom practice with engaging topics aimed at younger students. The information, practice and advice contained in the course ensure that they are fully prepared for all parts of the test, with strategies and skills to maximise their score. This Workbook without answers includes 14 topic-based units for homework which cover reading, writing and listening skills. It provides further practice in the grammar and vocabulary taught in the Student"s Book. The Audio CD contains all the listening material for the Workbook.