QUILL, a set of microcomputer-based writing activities for students in grades two through twelve, is based on the recent research on the composing process. To help students become more experienced writers, QUILL includes two tools for writing: a planner, which helps students plan and organize their pieces, and a writer's assistant or text editor, which facilitates the revision process by making the addition, deletion, and rearrangement of text easier. QUILL also provides students with two contexts for writing. The first is an electronic mail system with which students can send messages to individuals, to groups, or to an electronic bulletin board. The second is an information management system in which writing is accessed by title, author, or keyboards. Observations from more than 150 classrooms showed children could use QUILL for genuine communicative purposes if they were provided with the right opportunities. However, QUILL's effectiveness depended on the attitudes teachers conveyed to their students about it, and on the teachers' decisions about how students were allowed to use it. (Included are six lessons on how best to use QUILL that were created during two years of field-testing in second through eighth grade classrooms.) (HOD)