Teachers of children of all ages are enjoined by the National Curriculum for English to develop their pupils’ ability to write in standard English. This study explores the implications of these injunctions by examining the use of non-standard dialect grammar in the writing of 362 texts written by pupils of 11 an 15 years of age. It is established that most of the forms used are found in all four of the geographical regions sampled. The grammatical features of these non-standard (...) dialects and the frequency with which they occur are itemised and compared with a study of spoken English based on the same corpus. There is found to be considerable overlap between these and other recent studies of non-standard dialects in schools, although non-standard dialects are used more widely in speech than in writing. (shrink)