Summary. Parts of books used in a well-known reading scheme were modified by the addition of diacritical marks to indicate the sounds of letters. Children using this diacritical marking medium were compared with matched children using orthodox versions of the books by means of the Burt Word Reading Test and the Schonell Spelling Test (Form B).
It was found that children who used this medium were superior in reading not only in their own medium but also in traditional orthography. Their spelling and the quality and quantity of their free composition was also superior.