Pablo Picasso understood what Project Zero is after.

"Every child is an artist. The problem is how to remain an artist once one grows up," Picasso said.

The nature of artistic activity and the development of artistic skill in children are major subjects of Project Zero, a 13-year research project that has had considerable impact on American thinking about artistic education.

It takes its name from the amount of knowledge available on the subject when the project began. One of its first battles was to demonstrate that its objectives were not impossible to achieve -- that artistic education and development can be scientifically studied.

For a good part of this century, the prevailing view has been that children's artistic impulses should be left alone to flower or wilt. Art has been a separate subject in schools, to be taught by methods different from reading, writing and arithmetic.

Not only did most educators reject the idea that art could be taught, but most psychologists also believed artistic activity too inscrutable to be studied.

"The gamble we've taken at Project Zero is to show that artistic creation uses the brain," co-director Howard Gardner said in an interview.

"Everyone in the arts knows this, but there is a sort of conspiracy of silence," he added. "You only have to listen to the shop talk of artists to realize how they're thinking and making decisions."

Many artists have sought to preserve the idea that artistic ability is intuitive. "When one is painting one does not think," Raphael said in the 16th century.

Picasso had a rejoinder to that. "Once I drew like Raphael, but it has taken me a lifetime to draw like a child," he said of his artistic development. t

With scientific or moral development, children simply get better with age, but there are paradoxical ups and downs in artistic development. One of the early high points is roughly between ages 5 and 7 that Gardner describes as a youthful golden age.

"The grand vision of Project Zero is to understand how all these things develop in the brain," he said.

The project, based at the Harvard Graduate School of Education, has most of its funding from the National Institute of Education. "We've basically been given a dozen years to do basic research without a gun to our head," psychologist Gardner said. The National Science Foundation and private foundations also have supported Project Zero research.

Its most ambitious project is a close study of nine children's developing abilities with seven systems of symbols. Beginning when the children were a year old, researchers have studied their abilities with language, drawing, three-dimensional symbols like clay modeling, body expression including dance, music, numbers and what most parents would call "make believe" play.

Children's amazing progress with language is observed by every parent. In the course of two or three years, a child goes from lisping one or two simple words to speaking sentences of considerable complexity.

Gardner argues that ability to deal with other symbol systems progresses as rapidly as does language during the same years.

For the first two years of life, an infant is learning many things but is pre-symbolic, Gardner said. "If you give him a pencil he will put it in his mouth."

The first wave of ability to handle systems comes in language and in the ability to play pretend games. "If you give a child a pencil and say 'draw a truck,' he is likely to make the pencil the truck," Gardner said.

A second wave comes at age 3 or a littler earlier, Gardner said. For the first time, a child will try to draw the truck. He becomes capable of simple representational drawing and can repeat the general contours of a song.

About a year later, the third wave brings a much better ability to deal with the details of a symbol system. A drawing of a face will now have the proper features and a song will have the correct number of notes.

The fourth wave, roughly at age 5, brings the child the ability to use one symbol system to refer to another and opens up access through drawing, music or language to the cultural world.

At this age, Gardner said, drawing is likely to be of enormous importance to a child.

However, by age 7, the child, if left alone, shows less need to use symbols other than language, according to Gardner, who takes the controversial position that there is a qualitative as well as quantitiative decline in drawing at this age.

The talented will be exceptions, Gardner said, and so will children in cultures that stress what we call an art.

Gardner argues that it is wrong for schools to isolate artistic skills from other skills and artificial to label the arts nonbasic to education.

Not only can artistic creation be aided by teaching, Gardner said, but so can the appreciation of art.

"It is not true that art speaks directly to children," he said. If children are left alone, he believes, it is likely that the whole world of art will be dead to them.

Project Zero research has branched to include children and television, children's development of metaphoric thought, and a study which takes seriously the idea that knowledge differs depending on how it is acquired.

For example, someone who hears a story on the radio may receive different knowledge from waht a reader of the same story learns.

"What we don't know will fill a lot more books than what we do know," Gardner said, "but it would be wrong to say we haven't made progress from zero."