The purpose of this study was to gain information about the high school general educational context for students with and without disabilities. A questionnaire was administered to general education teachers who taught required high school courses in which students with disabilities and students who were low achievers were enrolled. Instructional context was explored in terms of (a) teachers' instructional roles and procedures; (b) curricular demands; and (c) teachers' views of research-based practices and standards. Participants were 70 high school teachers employed in nine public high schools serving grades 9 through 12 in four states, who taught one or more core classes in which students with disabilities were enrolled. In terms of their instructional roles and practices, teachers indicated that they preferred showing students how to learn at the same time they taught content. Planning time was limited, and unit tests or daily assignments, homework and worksheets were the most common forms of assessment. Teachers reported a willingness to make accommodations in curriculum materials, but did not report a high degree of use of accommodations in actual instruction. In reporting curricular demands, teachers put more emphasis on the mastery of content knowledge for students without disabilities, but for students with disabilities, the emphasis was on mastery of basic skills and strategies. As expected, participants indicated more learning deficits and reported lower expectations for students with disabilities than for other students. Teachers' perceptions of their schools' support for the use of research-based instruction varied. Teachers believed that typically achieving students were more likely than students with disabilities to meet standards. Teachers had recommendations they believed were needed to ensure that students with disabilities would meet standards. (Contains 6 tables.)