"We all are a part of it. That is the heart of it. We all have something to give. All races and creeds bring their talents and needs . . .

"Indians, Africans, Hispanics and such; an assortment of people like the English and Dutch; Asians, Rumanians, Poles and Swedes; came to see if this land filled their needs. . . ."

These words -- part of a song that is not on the Top Forty charts but could be if marketed commercially -- have been central to a living history project at the Norwood School in Bethesda for the past three years.

Every student who has been enrolled at the school over this period, from kindergarten through sixth grade, has taken part. The purpose of the project was to make history come alive through musical drama -- three of which culminated each of the recent school years. The first production covered the years 1776 to 1840, the second from 1840 to 1900.

"Twentieth Century U.S.A." was the final presentation this year, portraying historical events as seen through the eyes of a variety of citizens.

One of the more intriguing aspects of this year's show was the heavy emphasis on economic events of this century. Economists, historians and journalists all have tried to chronicle such events as the stock market crash of 1929, the Great Depression and New Deal, the impact of advertising.

Somehow, the Norwood children and project-music dirictor-songwriter Jean Lutterman and drama-research-director Rosa Scott seem to have made some sense of it far fewer words.

One example from the Roaring Twenties section: "I used to have a fortune. On Wall Street I was known. I played the market skillfully. My portfolio had grown.And I began to borrow 'til I was heavily in debt; and if the market hadn't crashed I'd be speculating yet!"

Fortunately, the work of these three years at Norwood, including viedeotaped recordings and full texts of the productions, have been preserved for other schools and generations to review, thanks to a grant from the National Endowment for the Humanities.

The point of this example is not an endorsement of continued funding for the National Endowment, whose finances are scheduled to be trimmed sharply in coming months under the Reagan administration's proposed budget cuts.

Rather, the Norwood experience and many other educational, health and cultural programs vital to fostering original thinking should serve as a reminder that if federal money is to be reduced, will anyone fill the void?

The business sector, which has had as much to do as any group with installation of the current administration's attempts at financial discipline in government, faces a major challenge in how it reacts to needs of this nation's nonprofit sector -- organizations from the Red Cross and United Way to the National Symphany Orchestra and community self-help groups.

Although little understood in terms of overall economic and social contributions, the nonprofit or independent sector consists of groups that focus on giving, volunteering and not for profit initiative. These philanthropic and voluntary programs add to the educational, scientific, cultural and religious life and health and welfare of America in a fashion that is unique to the world. In other nations, the billions of dollars of activity represented by these organizations are the province of government.

A new study, completed in the wake of President Reagan's proposed budget restrictions, is very gloomy about the prospects of this sector.

Private philanthrophy and voluntary organizations cannot cover a signficant proportion of the federal budget cuts in their areas of activity and, unless immediate steps are taken to stimulate giving, will not even come close to covering the direct losses to the budgets of these groups.

This conclusion was detailed by Independent Sector, an alliance of groups engaged in philanthropy and voluntary action, and in an analysis commissioned from the Urban Institute.

Lester Salamon, who conducted the Urban Institue study, indicated that nonprofit organizations such as private colleges and homes for the aged will lose $27.3 billion from their budgets (funds that would have flowed to them under budget provisions as recently as January) as the result of the proposed cutbacks.

Brian O'Connell, president of Independent Sector, indicated that even this example of the cuts to voluntary organizations is likely to come out low because the figures exclude other reductions almost certain to be made by state and local governments in response to their own losses from federal income. Overall, cuts in areas generally served by voluntary institutions would total $128.2 billion between 1981 and 1984.

O'Connell pointed out that the problem for voluntary organizations will be compounded by an almost certain increase in expectations of service. For example, if local governments must cut back on local day-care services, parents will turn to voluntary day-care programs, such as church-related services, to meet their needs.

The most serious problems is that while total giving in the private sector from corporations, foundations and individuals was $48 billion in 1980, this figure is exactly the same as five years ago when adjusted for inflation.

Corporate giving rose approximately 15 percent in both 1978 and 1979, but the acceleration dropped to 4 percent in 1980, a recessing period for many businesses. The total, however, is still only $2.5 billion or 5 percent of philanthropy. Even if corporte giving were to rise 15 percent in 1981, that increase would only be $375 million nationwide. Foundations will help even less. Ten years ago, foundations represented 10 percent of all U.S. phillanthropy. In just a decade, the proportion has dropped to 5 percent.

According to O'Connell, for the long term it is personal giving that will represent the greatest hope for carrying on many of the programs and organizations, but the turnaround will be slow. Giving by individuals represents 90 percent of all philanthropy in the country, but has been declining as a share of personal income and gross national product. In the face of continued inflation, it is not realistic to expect individuals to pick up the slack suddenly.

O'Connell concluded that the proposed federal budget cuts far exceed what the nonprofit sector can be expected to absorb and will lead to a very real question of whether many private institutions will be able to continue.

He called on the Reagan administration to help stimulate private giving. A first priority on his list is charitable contributions legislation, now before Congress, which would allow taxpayers to deduct their giving and increase such contributions by an estimated $6 billion a year.

And business people, who sincerely advocate more self-reliance and fewer appeals to Washington for any kind of assistance, must begin immediately to reassess their own charitable contribution programs and to ascertain how else they can help the nation's rich history of voluntary activity.

Business complains, for example, about the absence of adequate economic education in our schools. As the Norwood living history example shows, that school's young graduates of June 5 will have as good an understanding of American economic history as many of the people in the business world now.