AFTER three years of work, District school officials now say they were ready to install their "competency-based" curriculum in every school. We will understand if the announcement of yet another curriculum plan for Washington's schools provokes a certain skepticism among some longtime observers. For we, too, remember the hoopla and the hope - soon to be dashed - that accompanied the various so-called innovative curriculum plans that inundated the schools in the early 1970s. But we have some hope for the new curriculum, developed by Superintendent Vincent Reed and his staff and approved by the school board, precisely because it's not a "new" curriculum, but a better-organized version of the present one.

For the last decade, the city schools, by default, have tried to teach students with a confusing jumble of curricula, each with its own set of textbooks, recommended teaching methods and grading standards. For example, the schools accumulated 60 different reading programs because school officials made no attempt to pare the number being used to those that proved most effective. That situation was mirrored, to a lesser extent, in nearly every school subject. The result was that, incredibly, there were no citywide standards that stated definitively what students were expected to learn by the time they reached the end of a grade. Now standards have been set in reading (the number of reading plans has been reduced to five) and every other subject for promoting or failing students.

Thus, there will be more homework and more testing, but no dramatic changes because the competency-based curriculum boils down to being simply an updated version of the old system of lessons, homework and frequent tests. Teachers in every subject from reading to foreign languages to science and mathematics are to base their lessons on curriculum guidebooks that spell out what skills students should be learning during the year. The guidebooks also include tests to determine if students are learning the lessons and ways to help them if they're not. School officials will use special tests developed for them as well as standardized tests geared to national norms to determine the effect of the curriculum on pupil performance.

This highly organized approach should help inexperienced or poor teachers because they can draw their lessons directly from the curriculum guides. And it should enable school officials to judge how good a teacher is. Most important, there will now be an easy-to-read barometer of how well students, teachers and the schools are doing. Given the serious academic problems of the District schools, we're not expecting quick improvement in pupil test scores or classroom work. But, after a decade of ill-fated curriculum plans, we think this may be the old-fashioned approach to education that many District students need.