Difficulty with auditory perception and/or auditory memory of letters to sound
relationship
Lacks morphological knowledge about root words and relationship among words
Lacks knowledge of common irregular words
Inability to perceive the whole in its parts
Reverses letters
Trouble with visual memory for sequences
What About Spell Check?
Students who have difficulty with spelling often construct words which do not approximate the intended word. Because the word constructed does not approximate the intended word the spell checker cannot suggest the correct word. Overall, studies show that only 30-80% of spelling errors are caught.
Spell checkers only identify the target words 53% of the time for students or adults with learning disorders.
Notably, the National Commission on Writing for America’s Families, Schools, and Colleges reported that 80% of the time an employment application is doomed if it is poorly written or contains misspelled words.
Why Our English Spelling System Is More Regular and Predictable Than You May Think
Surprisingly enough the spelling of words in English is more regular and pattern- based than commonly thought. Actually, based on the works of Hanna, Hanna, Hodges, and Rudorf (1966) half of all English words can be spelled accurately on the basis of sound-to-symbol relationship alone. This means that letters used for spelling these words are predictably representative of their sound patterns (e.g., day, tray, play, baby). These patterns must be learned and are considered complex (e.g., when to use “k” as in cook and “ck” as in “pack”). Based on sound-to-symbol relationship, an additional 34% of English words would contain only one error using this method to spell.
Overall, that means that the spelling of 84% of English words is predictable.