I was pleased that The Post's editorial on the wall chart {"Test Score Perplexities," May 7} calls for better indicators to measure America's progress toward our national education goals. I would be the last person to claim that the wall chart {which provides state-by-state statistics on educational achievement based graduation rates and average SAT and ACT scores} is perfect, but it is the only state level assessment that we have available. The National Assessment of Educational Progress, with its focus on specific subject matter and on a range of ages, provides us with more information for judging educational performance than do college entrance tests. Once NAEP is able to report state-by-state results it will be useful as an accountability measure. However, even state-by-state indicators are of limited usefulness for encouraging reform.

Education reform is primarily a matter not for states or even districts, but for schools, principals, teachers, parents and students. Our ultimate aim is to develop a variety of indicators, not just test scores, that provide information on educational performance that is useful to school officials and teachers.

Finally, until we develop better measures of performance we will have to rely on the indicators we have. The wall chart despite its limitations, provides us with some measure of educational performance. Indeed, the wall chart has already had an impact. Many states and local districts are publicizing the performance of their school systems. We know that we need better answers to the question: How well is our education system doing? Before the wall chart, we didn't even have a way to ask the question. LAURO F. CAVAZOS Secretary of Education Washington