A study investigated the development of information processing as it relates to the development of reading skills by studying how good readers and poor readers utilized orthographic information. Subjects, 90 good and poor readers from grades 2, 4, and 6, participated in four 30-minute sessions in which they were required to make a same/different judgment after the presentation of two letter-strings were displayed successively on the computer monitor. An analysis of variance on the accuracy and latency measures indicated: (1) orthographic information continued to develop throughout grades 4 and 6; (2) poor readers were less skilled than good readers in orthographic information usage and made more phonemic, visual, and letter-order errors; (3) all subjects were affected to some degree by the greater load placed on working memory by longer letter-strings; and (4) the role of visual processing in orthographic information usage was further supported by the results obtained on a multiple regression which included cognitive, linguistic, visual processing, and memory test measures. (Six tables and 12 figures of data are included; 15 references are attached.) (RS)