Carlos, 6, picked up a fistful of crayons and the heavy plastic page of a specially designed coloring book. He selected a stick of crayon and filled in an apple-shaped figure with red. Then he colored the stem brown.

Although such a task is simple for most children, it was a major accomplishment for Carlos, a blind kindergarten student and a client of the Commission for the Blind in Alexandria.

Carlos is among millions of handicapped children and adults who have long been unable to find outlets and opportunities for artistic expression.

But newly enacted legislation that mandates that the handicapped be in the mainstream of public social and educational activities and changing public atitudes have sparked development of numerous programs in art for the handicapped.

"There are many handicapped kids who for instance will never be able to express themselves verbally or in writing," said Wendy Perk, executive director of the National Committee, Arts for the Handicapped. "The arts provide a medium of communication and expression for them."

When the national committee was ereated three years ago, Perk said, only about 12 percent of the nation's 8 million handicapped children had been exposed to any type of art experience.

With the new wide-ranging programs in art for the handicapped, she said that every disabled individual will soon have opportunities for self-expression through art where possible.

"We have found in projects across the country that the arts are an important teaching tool for the handicapped kids," she said.

The new awareness of the potential inherent in such programs has opened a number of opportunities to the handicapped that did not exist before.

Next Saturday for instance, handicapped artists from across the state of Maryland will participate in a statewide "Very Special Arts Festival," sponsored by the National Committee, Arts for the Handicapped through the Maryland-National Capital Parks and Planning Commission.

"We're expecting some 4,000 people from throughout the Metropolitan Washington area," said Marian F. Hosmer, coordinator of the festival. "We will have bands, clowns, song signers (persons who translate the lyrics of songs into manual signs for the deaf) and dozens of art exhibits."

"One of the most important benefits of the festival is that it provides a way for everybody to communicate and express their inner feelings," she said.

On June 21, 1975, the committee sponsored its first festival of arts for the handicapped in Washington state, where disabled persons displayed their art and artistic abilities and professional artists performed for the handicapped.

Last year other arts festivals for the handicapped were held in 27 states. This year 47 states are scheduled to hold the "Very Special" festivals. And the remaining states are expected to join the ranks in 1979.

Among the new developments for art expression by the handicapped are such items as the "coloring book for the blind," a reusable plastic book invented last year by Jacquelin V. Boston, a resident of Oxon Hill.

The book - created for children who are legally blind, but have enough vision to discern light, shapes or colors - consists of heavy plastic pages in which the figures to be colored are indented and outlined with a bold black line. Coloring instructions are in braille as are color identifications on the crayons.

The American Foundation for the Blind estimates that about 75 percent of the nation's 1.7 million blind individuals have usable vision, although they are classified as "legally blind."

Boston, an employe in the special education program of the D. C. public schools, sees major implication for a coloring book among the blind.

"For the partially sighted child, this specially designed coloring book can possibly provide the child's first opportunity to color or even draw a picture," she said.

"For the child who is totally blind and has no concept of color, the book can still be used to improve motor coordination and gives him something he can share with sighted friends," she said.

In Stockton, Calif., at the Alan Short Center, a cultural center for the physically and mentally handicapped, a group of students with various handicaps has performed a musical play entitled "Fatso" 50 times in three states.

The play, written by Joseph Parente, an instructor-therapist at the center, examines superficial social standards and their effect on one's feelings of self-worth.

Another group of students at the center participates in a Swiss hand bell choir, designed to teach each student such things as rhythm, note reading and harmony, while also stessing self-descipline, the importance of motivation and pride of accomplishment.

Other students at the center are learning "perceptual awareness" through projects in sculpture and improved social skills, graceful movement and how to respond quickly to instructions by square dancing.

Alan B. Falstreau, executive director of the Alan Short Center, which opened two years ago said the center has been able to take handicapped adults with a variety of behavioral problems and help them become aware of their own social needs through art projects.