The emerging field of participatory design is devoted to involving end users of a new technology in the design of that technology. This paper presents a case study of the participatory design of educational software and discusses guidelines derived from federally-funded formal research on participatory design projects. The case study involved the introduction of new computer technology (a newspaper editorial system) into the curriculum of a Boston public high school English department, which previously had no computer technology available in the classroom. In order to adapt the editor-writer model for the classroom, the editorial system needed to be customized. Customizations fell into three categories: information flow, security, and usability. While the design team included both teachers and engineers, the design effort was lead by a former English teacher turned computer scientist. This "translator" enabled the teachers to participate in the customization process by mediating between their language and workplace conventions and those of the software engineers. The formal retrospective study examined this project as well as another project that involved introducing new technology into the classroom. Guidelines for future participatory design projects were derived from interviews of the project participants, which included teachers, administrators, university researchers, and corporations. (Contains 15 references.) (AEF)