Teachers participating in a 12-month study investigating teacher response to computer innovation in the classroom reported several factors as influential in determining how computers are incorporated into classroom routines: the support they received; private and public expectations for the teacher and the school; ministry and board guidelines; and the rather unique process of innovation in which the teachers themselves were involved. Working with grades 4 to 10 in eight schools, case studies were compiled that document in detail both how and why individual teachers use computers. Although the schools chosen offered a wide range of computer applications--e.g., using the computer for graphics, for geographical simulations, for special education, for French immersion and for core French--the studies fell into two distinct groups: computers as part of a literacy program, and use of computers as a teaching tool. These two patterns of use differed in goals, learning potential, demands on the teacher, pedagogy, and curriculum implications. Of the two, computer literacy was the most problematic because of its newness and uncertain status as a subject. (DJR)