When teachers of handicapped children at Key Center first deicded to build a playground at the school, says Joan Jason, cochairman of the project, "we didn't know the first thing about what we were doing."

But a year and a completed project later, Jason and her organizers have become experts. Here's their advice:

1. Learn everything you can about what you want to do.

Before they began planning the playground, teachers at Key Center pored over dozens of articles about children and the development of play.

2. Appoint leaders with clearly defined responsibilities.

"The main thing is to be super-organized," says Jason. "Generate as much communication as you can."

The Key Center group, for instance, selected two leaders as cochairmen, then split the primary responsibilities among five committee chairmen. Those areas of responsibility were: fund raising, obtaining materials, recruiting volunteers, obtaining food for workers during the actual construction period and organizing baby-sitting services for children of the volunteers while they were on the work site.

3. Don't be afraid to hire an expert if the project is a large one.

Key Center organizers hired well-known playground architect Robert Leathers to design the playground and provide advice on organizing the project. On a smaller project, you might be able to persuade an expert to volunteer his or her time.

4. Use community leaders, both elected and appointed, to help generate support.

With the help of Jack Herrity, chairman of the County Board of Supervisors, for instance, Key Center project coordinators enlisted Flow General Inc., an international corporation that deals in high technology development for defense and bio-medicine, to serve as an umbrella for contact with community groups. The company formed a business construction committee to coordinate donations of money and materials.

Flow General, which is headquartered in Fairfax County, and the Key Center organizers split the work of soliciting money, volunteers and labor.

There are, incidentally, some things to consider when seeking any help in the form of donations or manpower, according to Jason.

"There's a real procedure to follow," she says. "First call and tell the business or organization what you need, then write a brief letter, then follow up with another telephone call."

"Learn to be savvy," she says. "Be polite and friendly, but be direct. Know exactly what you need."

Also, get to know secretaries and remember names: the name of the salesman at the hardware store, the name of the public relations officer of the corporation, the name of the president of the civic club.

5. Contact anyone and any group that could help.

Committee chairmen blitzed community groups with letters and brochures about the project. In addition to seeking financial and material support from businesses and civic groups, the manpower committee chairman sought volunteers from military bases and military organizations and secured more than 150 volunteers from the Air Force, the Pentagon and the Navy Seabees. The food committee solicited donations of food from area restaurants and fast-food chains.

The most difficult task of the project, says Jason, was finding volunteers and equipment for the heavy projects: backhoe operators to dig up the old asphalt and equipment to position the telephone pole supports used to anchor the playground. In the case of the telephone poles, for instance, committee members persuaded C&P to provide help. A man who operated a backhoe, who was a friend of a parent, was enlisted to dig up the asphalt.

6. Be flexible.

The project design for the playground was altered continually throughout planning and construction. Before the finishing touches were added, the youngsters were allowed to test the playground and recommend alterations.

7. Be prepared for the worst . . .

Such as undelivered lumber, the sandwich shortage, the unexpected rainstorm. Always have backup plans.

"Anticipate the absolute worst," Jason warns potential project organizers. "Overshoot how much money you're going to need and allow for a lot of waste -- with donated materials you'll find a lot of damaged wood and other material."