Most policy makers, corporate executives, practitioners, and parents assume that wiring schools, buying hardware and software, and distributing the equipment throughout will lead to abundant classroom use by teachers and students and improved teaching and learning. This article examines these assumptions in two high schools located in the heart of technological progress, Northern California’s Silicon Valley. Our qualitative methodology included interviews with teachers, students, and administrators, classroom observations, review of school documents, and surveys of both teachers and students in the two high schools. We found that access to equipment and software seldom led to widespread teacher and student use. Most teachers were occasional users or nonusers. When they used computers for classroom work, more often than not their use sustained rather than altered existing patterns of teaching practice. We offer two interrelated explanations for these challenges to the dominant assumptions that guide present technological policy making.