A YEAR OF school runs 200 days in Scotland and the Netherlands and even longer in Luxembourg. But the world's academic standard-bearers are found along the Pacific Rim, where students in South Korea, Taiwan and Japan spend 220, 240, and 243 days of the year, respectively, in the classroom. In these times of increasing international competition and with the United States ranking no better than 19th in the world on this index with a 180-day school year requirement, one might expect a ground swell of support for a longer school year. But this kind of talk generates strident opposition.

Recently, the Maryland State Board of Education urged a 20-day extension of the school year to 200 days. Virginia Education Secretary James W. Dyke Jr. was more emphatic, asserting the need for year-round classes. Local school superintendents and members of boards of education in both states quickly set upon the ideas. What would we use it for, they asked? We'll answer that with questions of our own. How about 20 days for the reviewing of covered material, or 20 more days of additional studies?

Parents, who ought to consider the long-range benefits to future generations, balk at the idea of putting off summer vacations for a couple of weeks. When the Polk County, N.C., school board tacked an extra month onto its school year in 1983, parents sued in court and lost and then launched a campaign that resulted in the landslide ouster of the board. The new board's first order of business was to return to the old school year. More recently, Ocean City businessmen lined up against the longer school year proposal in Maryland. It would hurt summer business and hamper summer hiring, they said.

There is just one valid reason to delay serious consideration of a longer school year: cost. Various estimates put the price tag for an extra month of school nationwide at $11 billion to $20 billion annually, and these are troubling economic times for the nation and for many states such as Maryland and Virginia. But Virginia Gov. L. Douglas Wilder says that some funding now spent on administration could be shifted to pay for a longer school term. That's certainly worth consideration, and it could begin with smaller increments involving a few days. This is no longer an agrarian society that depends upon a long summer recess to benefit the old family farm. It's a society that badly needs to increase the academic preparedness of its young in relation to the rest of the industrialized world.