Large classrooms have traditionally provided multiple blackboards on which an entire lecture could be visible. In recent decades, classrooms were augmented with a data projector and screen, allowing computer-generated slides to replace hand-written blackboard presentations and overhead transparencies as the medium of choice. Many lecture halls and conference rooms will soon be equipped with multiple projectors that provide large, high-resolution displays of comparable size to an old fashioned array of blackboards. The predominant presentation software, however, is still designed for a single medium-resolution projector. With the ultimate goal of designing rich presentation tools that take full advantage of increased screen resolution and real estate, we conducted an observational study to examine current practice with both traditional whiteboards and blackboards, and computer-generated slides. We identify several categories of observed usage, and highlight differences between traditional media and computer slides. We then present design guidelines for presentation software that capture the advantages of the old and the new and describe a working prototype based on those guidelines that more fully utilizes the capabilities of multiple displays.