The House of Representatives Committee on Education and Labor asked the General Accounting Office (GAO) to look at school testing as it exists, to estimate its extent and cost, and to assess how a new national test might affect those factors. GAO gathered information from a variety of sources, including a 1991 survey with replies from 48 states and 74% of local districts in its national sample. U.S. students in 1991 did not appear to have been over tested, with systemwide testing taking up about 7 hours per year for an average student, half in testing and half in related activity. The overall cost in 1991 was estimated at $516 million, an estimated $15 per student. A future national test, whether a single performance-based test, a multiple-choice test, or tests for a decentralized system of clusters of states, would range from about $160 million for the first option to about $330 million after development costs for the cluster option with a performance-based test. However, there was significant opposition among respondents to the concept of a national examination system. The GAO believes that if the Congress wishes to mandate a national examination system, efforts should be made to involve local teachers and administrators, as well as to ensure the technical quality of the test. Four sources are listed for further reading. (SLD)