This paper looks at the spelling errors that occurred in the spontaneous writing of 12-year-old children. A number of errors occur that are not addressed by the conventional approaches to spelling and which we can best understand by taking account of the psychological context in which they occur. One set of errors relates more to incorrect articulation than to poor spelling. A second set indicates the role of morphemic factors in the spelling of inflected words. Two other sets, one consisting of lexical substitutions, the other of words split into two parts, indicate the existence of a device that monitors the identity of what we write.