No one knows exactly what has caused the striking decline in the quality of American education, especially in science and mathematics. That a deterioration has been under way-- perhaps for as long as two decades--is clear. That it has coincided with the opposite trend abroad is also beyond doubt. While American educators focus on the failure to learn "basic skills," the Soviet Union, Japan and many other countries are making great advances both in the proportion of students who complete secondary school and in the breadth, depth and rigor of what they are taught.

One factor in the United States' dismal performance is unquestionably too much television. Seventy- five percent of last year's high school graduating class reported spending less than five hours per week on homework. Twenty-six percent of them reported four hours or more per day watching television. In a 1973 survey of science education in 19 European and Third World countries, the only measure on which American students scored above the mean was in hours spent watching television. The result is a pervasive intellectual passivity and a large number of students who never learn to read well enough to acquire the taste for it.

Another cause is the decline in the quality, and even availability, of teachers, especially in science and mathematics. Twenty-five years ago teaching was the only socially acceptable career for many bright, motivated women; today they have other options. Men and women with science training can earn far more than a teacher's pay working as computer programmers. Chronic vacancies for mathematics teachers--as high as 25 percent in some school districts--are filled by those without training in mathematics. There are 10,000 physics teachers in the nation's 16,000 school districts. Lack of public concern for the quality of education, lack of respect for teaching as a profession, lack of support systems to keep teachers up to date in their fields and appallingly low pay are all having the predictable result. Morale in the schools is spiraling downward, and college graduates going into teaching consistently come from the bottom of their classes.

Numerous studies have postulated other causes: too much violence and too little discipline in the schools, too much latitude in course selection, too much encouragement and opportunity for students to do things other than study, too much stress on basic skills that makes this minimal achievement the goal rather than the foundation for further learning, and so on.

But to a certain extent these phenomena must be symptoms rather than causes, for what happens in the schools is a reflection of the values and expectations of society at large. Alexander Astin, professor of education at UCLA, writes: "The schools are just less demanding than they used to be and (students) are lazy up and down the ability spectrum." What we seem to have suffered, in short, is a loss of appetite for the hard work of learning and an appreciation for the results.

This is not the first time American education has fallen behind. What is scary is that this time we as a nation don't seem to care--or care enough. When the launch of Sputnik in 1957 brought recognition that U.S. science education badly needed improvement, we responded with new courses, textbooks, teacher training and curricula. Though there were some problems, the effort did produce more and better-educated science and mathematics graduates. This time there has been no single jolting event, but evidence of a far worse slump is everywhere. And this year the federal budget cuts wiped out the agency responsible for the post-Sputnik science program--the only single focus for such an effort in the nation.

We ignore what is happening in the schools at our peril. The United States cannot compete in the world economy without a technically skilled work force, nor will any amount of money spent on weapons buy security without men and women capable of using them effectively. Far more important, we cannot hope to sustain a democracy, the most demanding form of government, without citizens capable of understanding the choices that have to be made.

Making up the lost ground, especially in science and mathematics, is going to require plenty of money, but without a well-educated populace what other investment is worth making? Most of all it will require a change in attitude--higher expectations of work and achievement. Years ago poor children on New York's Lower East Side were sent off to the first day of school with a gift of honey and nuts to symbolize the sweetness of learning. That attitude, and a school system that made knowledge available to everyone who wanted it, were what made this country great. It's not gone, it just needs to be recaptured.