Key Spelling is a series of graded activity books containing puzzles and problems that will reinforce children's essential spelling skills and knowledge. Key Spelling Book 1 covers: single consonant sounds made by more than one letter (for example 'ch' 'sh' and 'th'), vowel sounds made by more than one letter (for example 'ea' and 'ow') and letter blends such as 'st' 'ng' and 'cr'.