* In 1980 a group of 30 housewives in El Salvador started a business making ketchup, sauces from tomatoes and peppers, and fruit jams. With a $3,000 profit last year and a loan to build a new processing plant, the business has significantly improved the lives of about 6,000 residents of El Castano. Co-op workers are now lending their expertise to neighboring communities.
* In Panama City, 117 women - all single heads of households - attended classes in business and technical skills to help them earn money and support their families. Classes are geared toward industries needing such skills as upholstering, cooking, commercial gardening, and sewing. Many of the women are employed in local companies, and 56 have started their own businesses.
* In Sri Lanka, 144 volunteers helped 4,000 rural village women start a variety of small businesses including child care, vegetable gardening, and raising chickens. The women are now taking home $16 more per month - a substantial profit in Sri Lanka.
These women and their families benefited from projects organized by Overseas Education Fund International (OEF International), a nonprofit group headquartered in the United States. Its goal is to help third-world women achieve economic self-sufficiency.
The success of their various programs has ''proved it is possible for women with marginal or no income to be economically productive,'' says Elise Smith, executive director of OEF International and president of Private Agencies for International Development.
Private voluntary organizations (PVOs), such as OEF International, Accion International, and the Trickle Up Program Inc., assist both men and women starting small-scale enterprises in developing nations. Food distribution and relief programs such as CARE and Catholic Relief Services, are also beginning to focus on self-help job-training programs.
Most PVOs aiding small-scale enterprises mobilize volunteers from existing development and government agencies in the third-world countries. By keeping their own staffs small, these organizations are able to minimize administrative costs and to provide maximum possible funding to those most in need. Many of these groups depend largely on private contributions.
Here are thumbnail descriptions of the three above-mentioned PVOs:
OEF International assists women in about 50 countries with loans from $50 to help women start or strengthen their own businesses and to prepare them for jobs in the formal business sector.
''Micro enterprises can be done from their homes or from a rented room in the community where they can be nearby their children,'' says Deborah Ziska, communications director of OEF International. ''We've seen these women and what they can do; they've done so much with so little.''
''One of the problems in the developing world is, not enough institutions are willing to give loans to low-income men and women,'' says Ms. Smith, who notes that third-world governments are beginning to realize the potential of small-scale enterprises, which are already a substantial portion of the economy - although definite figures have not been compiled. ''As these businesses multiply it adds to the total economic productivity of the entire country,'' she says. Accion International
Accion International, also headquartered in the US, provides loan capital, technical assistance, and management training for small enterprises in seven countries: Peru, Ecuador, the Dominican Republic, Mexico, Costa Rica, Jamaica, and Colombia. More than half the organization's funding is provided by multinational corporations.
Accion works with market vendors and cottage industries to help guide them into the mainstream economy. The organization provides these individuals and small groups with the initial capital to build their businesses to the level where they are eligible for commercial bank credit and other public services.
All loans, which range from $50 to $1,500, must be paid back with interest. According to Fernando Quezada, director of development planning, this helps the business gain a credit history so commercial banks will take them seriously.
''Accion is sometimes criticized for charging interest on its loans,'' he says. ''But we're training these (entrepreneurs) to play in bigger leagues. It's part of a person's dignity to play within the rules.''
The majority of business people sponsored by Accion are women. In Peru, for example, 60 percent of the beneficiaries are women; in the capital, Lima, 80 percent are women.
''Women are the most oppressed,'' says Mr. Quezada. ''There are very many common-law marriage situations. If the husband walks out, the woman can do nothing except go out on the street and sell vegetables.'' Trickle Up Program Inc.
The Trickle Up Program Inc., founded and run by Glen and Mildred Leet, is open to both men and women in developing countries. Trickle Up is helping increasing numbers of young people and, currently, about 80 percent of those involved in projects are women.
''Women are the last to be offered anything in terms of technology and training,'' Mrs. Leet says. ''Many are single heads of households with total responsibility for the care and feeding of their children. They have long been the invisible contributors to society. In many of these countries they are often the producers and marketers of food and clothing.''
Groups of five or more people may apply for an initial $50 grant from Trickle Up to start an enterprise they have planned themselves. They must agree to invest at least 1,000 hours of self-employment during a three-month period and reinvest at least 20 percent of their profits. After submitting a progress report, the group may qualify for a second $50 grant.
About 800 Trickle Up-sponsored projects now operate in 67 countries. Activities include the production or growing and marketing of a wide variety of items including bakery goods, baskets, brooms, clothing, poultry, and vegetables.
In Costa Rica, a group of five young women started a children's clothing business with a $50 loan from Trickle Up. As their enterprise progressed they were able to secure a loan to buy a house for their business in San Jose, the capital.
''These are survivors we're talking about and now they are getting beyond survival,'' says Mrs. Leet. ''Their quality of life and state of mind are improving.''