Ol' MacDonald (Had a Farm)" might be common fare for most kids, but the crying and cheering parents applauding the 12 diminutive graduates singing and signing the verses last week, showed it was quite an accomplishment for their youngsters.

These were special children. All pre-schoolers, they had overcome speech and hearing problems to sing, sign and play the old farmer's animals.

One of them is a boy we'll call Tommy. He was not the typical three-year-old. He had a four-word vocabulary -- his name, his mother's, brother's and sister's -- while other children his age were speaking 200 to 400 words. His mother made excuses for him, obscuring his inability to communicate.

E. Elaine Vowels, director of the District's Model Pre-School language Development Program, said a national study by Head Start indicates that approximately 53 percent of the pre-school aged children eligible for the program might have speech and hearing problems.

Nationally, about one in five children is eligible for the Head Start program. Of the remainder, in D.C., an estimated 25 per cent might be having speech and hearing difficulties.

A number of private clincis are available locally for speech and hearing therapy, Vowels said, and D.C. has three public clinics -- the Health Centers for Mothers and Children, No. 17 at 702 15th st. NE and No. 18 at 4130 Hunt Place NE and the D.C. General Hospital children's clinic.

Last Friday, 12 formerly shy youngsters who completed a one-to two-year program designed to develop speech, language and hearing skills, donned caps and gowns and were awarded graduation certificates at the Hunt Place clinic.

It was an emotional ceremony as parents heard and watched their children, who had had such speech problems as stuttering, incorrectly naming objects and speaking unintelligibly -- sing. The hearing impaired youngsters signed "I Love You."

Thus, the efforts of a speech pathologist, and audiologist, a parent coordinator, several therapists, a bus driver and a secretary helped to produce another group of potentially successful students for the 10th consecutive year.

Joan Lewis, mother of 5-year-old twins Michael and Mitchell, said it is hard for parents to understand that their children might have special problems. "You're sometimes overprotective. You see a problem in a child and can't face the fact that he's not perfect," she said. "He'll get better you'll say, then you put your head in the sand and forget it's a problem.

"That's true more often with fathers thinking about their boys, because fathers are so worried about the 'macho' image."

Elaine Vowels said the therapy "prepares children to communicate by increasing their vocabularly and providing practice in the standard syntax, grammar and articulation of speaking patterns."

Youngsters are brought into the program after a series of tests to judge their speech and auditory skills. Parents are alerted to any potential problem when they take their children for diagnosis at one of the three clinics. Parents are advised to check for speech and hearing loss in 2-to 3-year-old children by asking questions like these:

Does your child use 2-to 3-word sentences?

Does your child ask lots of why and what questions?

Does your child like to name things?"

A negative response should prompt a parent to inquire about speech and hearing tests.

Therapy includes activities for the youngsters to stimulate communication, Trips to the circus, the National Zoo, museums and other places encourage children to talk, Vowels said.

Madlynn Entzminger, staff supervisor, said some of the difficulty in communication may be related to parents not speaking standard English in the home, but the major culprit for many speech deficiencies is lack of stimulation.

"Sometimes the parents don't talk to the kids. Without talking or communicating the children aren't stimulated to develop their speech."

The program is designed to teach a child the basic speech concepts and sigh language in two years -- meeting from September to June four days a week for two hours.

To ensure better communication away from the classroom, a parents' club is formed.

"They have a waiting list because so many children need help," said Lewis, president of the parents' club for her sons' class.

However, Vowels said the wait is short because a child is either admitted or referred elsewhere.

The program has been a tremendous help to her twin sons, Lewis said. "Michael talks so much now I wish he'd shut up sometimes," she laughed.