A lexicon of approximately 9,000 words classified into levels from kindergarten to grade 3 was compiled as a base for studying the spelling-to-sound correspondences needed in beginning reading. The spelling-to-sound correspondences were established for 69 grapheme units, resulting in a total of 166 correspondences for the one- and Two-syllable words in the lexicon. These words were coded for the correspondence number of each grapheme unit, stress, syllable division, form-class, grade level, and special word conditions. Then 6,000 coded words were computer-processed and arranged by correspondences in a sequence for use in an instructional program. This systematic arrangement of words provided for the gradual increasing of word length and for organized introduction of vowels in unstressed syllables. The sequencing also allowed each one- or two-syllable words to appear as an exemplar of only one correspondence, after all other correspondences in the word have been introduced. The uncoded words of three or more syllables were arranged in the sequence by hand, bringing the total number of sequenced correspondences to 186. Finally, all lexicon words, including exceptions to the correspondences and proper names, were arranged according to the sequence. References are included. (AW)