Small computers are emerging as important components of the contemporary computing scene. Their operating systems vary from specialized software for an embedded system to the same style of OS used on a generic desktop or server computer. This article describes a course in which systems are classified by their hardware capability and the traditional OS topic areas are then dissected, augmented, reassembled, and reorganized to illustrate the aspects of each topic as applicable to each class of small computers. Ultimately, the course covers the same material as a conventional OS course, but from a new perspective.