Book 12b" explores Peter & Jane's mountain adventure in 131 new words including 'goodbye' 'suggested' 'clouds' & 'discussed'. Once this book has been completed the child moves on to book "12c". " The Key Words with Peter & Jane" books work because each of the key words is introduced gradually & repeated frequently. This builds confidence in children when they recognise these key words on sight (also known as the 'look & say' method of learning). Examples of key words are: the one two he. There are 12 levels each with 3 books: a b & c. " Series a": gradually introduces new words. " Series b": provides further practise of words featured in the 'a' series. " Series c": links reading with writing & phonics. All the words that have been introduced in each 'a' & 'b' book are also reinforced in the 'c' books."