Using J. Dewey's "reconstruction of experience" concept of revision, a study employed ethnographic methods to investigate the effects of computer assisted writing instruction on students' revising processes. Primary subjects, eight sixth-graders, completed a structured revision task on their compositions, with varying degrees of computer interaction. Data sources included fieldnotes, interviews, audiotapes, videotapes, and writing samples. Retrospective interviews were conducted with the two primary case study writers, and their experiences were related to the revision patterns of 61 students in four classes. Statistics showed that students using computers to revise their compositions wrote longer papers and received slightly higher holistic scores. However, findings revealed that the most striking differences had little to do with computers--class means corresponded dramatically with instructional emphasis. Results suggested that students revised according to a construct of "good writing" that could be linked to three instructional emphases: fluency, word choice, and mechanics. Results also indicated that revision of fluency, word choice, and mechanics could be taught. Thus, the results suggest that the revision process is driven by instructional emphasis, not computer interaction. (Interviews and scoring of the two primary case study writers and statistical tables are included.) (JD)