The art that we call "student work" is all too often dutiful, clear and trim and dull. Though the four young artists showing at the WPA (1227 G St. NW.) are all recent graduates of the Corcoran School of Art, their slightly messy work is not like that at all.

It is scattered, odd, exuberant. Above all it is personal. Angela Cockman, Cathy Coyle, Jim Duckworth and Jim Mullen do not regurgitate their lessons or bore us with their theories. Their sources lie within them. They were taught - or taught themselves - to ransack their reveries, to scavenge their old dreams.

Duckworth dreams of battles. His portion of the show would be a self-portrait were he a tin soldier. On a field of green baize, among cotton puffs of smoke, his tiny metal comrades march in nice formation. The medals they will win (he made them out of tinfoil) are hanging on the wall. So are their spyglasses and flags.

Duckworth's show includes little deer who flee the din, battlecries and a bemused, self-confident note of explanation: "Speaking from a tin soldier's viewpoint, art and surprise are on our side." The colors he prefers are childlike and cheery, and his wars produce no pain.

Angela Cockman's dreams, though stranger, are equally romantic. Rosecliff, that enchanted house above the stormy sea, is their setting.Her props are real things - comfortable chairs, a sewing box, old albums and old doilles - but their reality is altered. She uses them to orchestrate odd, obsessive dreams. We learn about the huge statue kidnapped from the park, though we never see its features. Geese fly above Rosecliff, and then they become teapots. To the viewer who is sitting there, his elbows on the doilles, the teapot at his fingertips, Cockman's show of things and paintings seems a Gothic novel brightened by delight.

Coyle sees the holy in trash on the street. She gathers what she finds there - old springs, cogs, gears, broken wooden paddles, the lids of old tin cans. "I have," she writes, "accumulated what is probably the largest private collection of junk in Washington." With it she constructs and assembled altars. Those old rusted lids become sun discs on new shrines.

The star of Mullen's show is the Knight in Armor who, in ragged, sometimes gross cartoons, undergoes assorted trials and adventures. He smells his boutomiere; he canoes Niagara Falls; he lifts the flowing robes of blindfolded Justice; he lets an arrow fly; he confronts the Barbarian who is his foe, perhaps his twin. The wildness of Mullen's drawing is a good reflection of the wilderness of his thought.

This show is far from dull. It is accompanied by an exhibition of the color photographs of Arthur Ollman, the San Francisco artist who likes to show us shadows as they loom at that strange time when day turns into night. The exhibits at the WPA will run through Sept. 30.

Washington's David Stephens showed us a few years ago a set of large and abstract paintings that cast a mood of glimmerings and twinklings in darkness. His studies for huge sculptures, now on exhibition at Gallery 10, 1519 Connecticut Ave. NW., also evoke night.

The sculptures he envisions, with their girders, beams and inclined planes, are structures with a function. If they ever are constructed, they will be used to study vision, heaven and the stars. Their ancestors include the observatories of India, Britian's aligned standing stones and megalithic circles, and the constructavist designs of the early-20th-century Russians. The pictures Stephens show us are paintings at the same time that they are working drawings. Construction drawings usually imply bright fluorescent light, but Stephens paints with darks, browns, maroons, and dusky blues that suggest the night. His exhibition closes Sept. 30.

The Adams, Davidson Galleries, 3233 P St. NW., are showing the picturesque-yet-spooky graphite drawings of Tom Jones. The artist lives in Falls Church; this is his first show.

His work, at first glimpse, looks like that of a hundred other artists who carefully portray old farmhouses, old barns, hillsides, leafless trees and other bits of rural life. Andrew Wyeth is their leader. Wyeth has a morbid streak. He is fond of winter, rotten wood, crows and other hints of death. These passages in Wyeth's work seem to urge the viewer to muse upon mortality, the parallel passages in the drawings of Tom Jones seem to suggest screams.

In an otherwise peaceful landscape, a hawk digs his talons into head of a fish. The curtains in the farmhouse window seem to writhe like entrails. We look into a patio. Is that blood upon the floor? The bit of cloth that's hanging there seems less a towel than a shroud.

Though the sweetness and the savagery he blends within his drawings sometimes seem to clash, Jones shows promise as a draftsman. His exhibition closes Oct. 10.

The Plum Gallery, 3762 Howard Ave., on "Antique Row" in Kensington, is showing the string constructions of Sue Fuller of Southhampton, N.Y. Anyone who has experimented with a ruler; drawing a sets of straight ruled lines that generate smooth curves, will recognize the one idea that dominates her show.

She makes her straight lines out of colored string, and frequently embeds her complex compositions in blocks of polished lucite. Sometimes she encloses them between sheets of glass. What she does, she does very well. She's been doing it for years.

Though the beauties of mechanical drawing cannot be denied, Fuller's art seems soulless. Its antecedents are too clear. She has acknowledged that when she saw the similar works of Gabo and Pevsner in the Museum of Modern Art, "the sight of all that string and lucite overwhelmed me." Fuller's works are as beautifully constructed, and as cold, as proofs in mathematics. Her exhibition closes Oct. 4.