Learning to read can be a daunting task for young children, but especially so for those with speech, language, or learning disorders. These children have demonstrated difficulty identifying, organizing, and generalizing the patterns of speech and language. At school age, these children are expected to become consciously aware of these patterns in oral language (i.e., phonological awareness) and then to associate the sounds, words, and sentences of English with a system of written symbols for reading and writing.

This task is difficult for many reasons. The first difficulty is found in the written language patterns of English. The principles of English spelling, or orthography, are very challenging since there is no direct phoneme-letter correspondence. Most phonemes are represented by one letter, but many (notably the long vowels, vowel diphthongs, and consonant digraphs) are represented by two or more letters. Similarly, the same phoneme may have many different spellings (e.g., /eI/ may be spelled “a,” “ai,” “ay,” “eigh,” or “a” + “silent e”). These spelling patterns occur with some regularity, but often there are as many or more words presenting exceptions to these “rules” as there are words conforming to the rules, since the same orthographic pattern can represent different phonemes within different words (note the pronunciations of the “ea” vowels in “head” and “meat”; Clymer, 1963). Many other words have irregular spellings that contradict the expected patterns.