The seven stages in the system development process are discussed in the context of implementing basic arithmetic drill and practice exercises on a computer-based system: (1) feasibility study; (2) requirements definition; (3) alternative specifications; (4) evaluation and selection of an alternative; (5) system design; (6) development and testing; and (7) implementation. The importance of considering the five components of a computer-based system--hardware, software, procedures, people, and data--at each stage is emphasized. A list of criteria for evaluating software is provided. (MES)