Caretha Hammond, 35, was two weeks pregnant with her first child in 1958 when she discovered that she had German measles. Doctors in her hometown of Salters, S.C., told her that the disease would have no effect on the baby.

But three months after her son - Clarence Milton Hammond - was born, Mrs. Hammond learned that he was completely deaf and had almost no sight. His handicaps were due, doctors finally concluded, to the effects of the German measles.

Mrs. Hammond, the mother of three, said she worked wth her son from his infantry for endless hours at home in an effort to help him somehow compensate for his handicaps.

"The doctors said Clarence would never be able to even thread a needle by himself. Other people said my son would never have the ability to cross a street alone," she said. "But I always believed he could do more than that. I never gave up."

The struggle has been a long one for Mrs. Hammond. She faced long odds that her son might never learn to speak or comprehend speech, doctors who felt her son should be placed in an institution, and the D.C. government which refused to pay her son's tuition at a special school for the blind.

Now Mrs. Hammond has a lot to be proud of: For the past two years, Clarence Hammond, 19, has been on the honor roll at the Perkins School for the Blind, in Watertown, Mass., one of the natin's west institutions for the blind. His top grades are in math, and one administrator said he is possibly one of the brightest students to attend the school since Helen Keller.

Recently, he was accepted - along with 10 of this blind classmates - at the Massachusetts Institute of Technology, where the group will study computer technology part-time on Saturdays.

When he graduated from Perkins in 1978, Hammond, who is also skilled in wood and metal crafts, plans to study data processing and computer programming at the National Institute for the Deaf at the Rochester Institute of Technology in New York. He eventually wants a career in the computer field.

Hammond has excelled in areas such as mathematics, language skills, art and architectural design, where mastery by a deaf-blind person wa once thought impossible.

Hammond the oldest of three children, was at home last week to visit his mother, and two sisters, Loretta, 17, and Velda, 16, in Lorton.

Traveling with him was his tutor-companion Chester Fair, a graduate of a special education program at Talladega (Ala.) College Fair, 24, was assigned two years ago to accompany Hammond to the classroom and translate verbal lectures and instructione into sign language for Hammond, who can "read" the signs using a small amount of residual vision in his left eye.

Hammond communicates either by "signing" with his hands, speaking haltingly or by writing out his messages on a pad.

"I feel good about being able to get into the course at MIT," Hammond told a reporter in signs which were interpreted by Fair. "I've seen their computer graph displays and I like them."

About his hopes for the future, Hammond said in signs: "I don't want to be poor. I'd like to be rich. I want to be able to help my family."

At Perkins, Hammond has been on the wrestling team for the past five years. For three years, he has won the school's championship for one-on-one basketball. In his spare time at school, Hammond occasionally helps other students who are not as good in math as he.

Hammond is one of between 10,000 and 15,000 deaf-blind adults and children in the United States. Although many can be trained in basic daily living skills, few deaf-blind persons have been able to follow complicated and academic courses of study.

The late Helen Keller, who lost her sight and hearing before she was 2, became internationally famous for her remarkable achievements.

Miss Keller attended Perkins and later graduated from Radcliffe College with honors. She was the author of more than nine books and lectured on the plight of the handicapped in 25 countries.

Helen Keller died in 1968, the same year that Clarence Hammond left his Southeast Washington neighborhood for the plush, Ivy League-style campus of Perkins. Since, he was emerged as one of the institution's brightest students.

"Clarence is one of the most promising deaf-blind students we'ver ever had," said Benjamin F. Smith, director of Perkins, where he said 70 of the school's 260 students are deaf-blind. "He has the potential to do well, in a variety of different kinds of employment."

But Smith hastened to add that, currently there are only about six deaf-blind persons in the nation who are capable of doing "academic quality work." He said that because Hammond is exceptionally skillful with his hands, he would probably excel in a career as a machinist or a computer technician.

But Mrs. Hammond believes her son can do more. "My husband was a plumber and because of the hard times he had. Clarence doesn't like that kind of work," said Mrs. Hammond. "My son dreams of having a job where he can wear a shirt and tie."

In 1971, Hammond became the center of a controversy when the city refused to continue paying a 56,000-a-year share of his tuition at Perkins, where he total cost was then $8,500.

After desperate pleas from Mrs. Hammond, the Department of Health, Education and Welfare agreed at the last minute to help the District pay the bulk of Clarence Hammond's education costs, which are now more than $11,000 year, D.C. now pays about $3,500 of that amount.

Last week, workers in the D.C. Department of Human Resources said they were excited about Hammond's academic achievements.

"Clarence has always been bery special to us," said Connie gant, a supervisor counselor at the Bureau of Rehabilitation Services. "We're proud of him."