With increased computer technology use in schools, preservice teachers must be prepared to deal with ethical issues involved in a range of computer uses, such as students plagiarizing from the Internet or accessing adults-only web sites. We investigated preservice teachers' judgments regarding several scenarios of student uses of the computer and Internet. Results show that most of the preservice teachers believed that appropriate uses of the computer and Internet involve specific classroom and school rules rather than universal considerations. We also asked the preservice teachers to predict elementary school students' responses to the same scenarios. Preservice teachers were at times able to predict students' judgments for whether the behavior was appropriate; however, they were unable to explain why students made those judgments. Our findings provide valuable information for teacher education programs on how preservice teachers can be better prepared for classroom incidents and, in turn, can help students understand the issues involved in various uses of the computer and Internet. (Contains 2 tables.)