To celebrate an important acquisition and its successful restoration, the National Museum of African Art has mounted an imperfect but intriguing little show about a shining moment in 20th-century Nigerian art.

Its title, "A Concrete Vision: Oshogbo Art in the 1960s," is a punning reference to the show's centerpiece, a four-part 5-by-14-foot openwork concrete screen featuring scenes of daily life in the prosperous southwest Nigerian city of Oshogbo, a major food-processing and shipping center for the surrounding farmlands. Commissioned for a Manhattan garden in 1966, it was made by Adebisi Akanji, a Yoruba bricklayer who became a successful sculptor after he was encouraged to enter various competitions and sell his work.

The show is really about the similar flowering of a whole group of Yoruba artisans who were introduced to the creative possibilities of nontraditional media in the workshops that sprang up around the Mbari Mbayo club and gallery in the '60s. The creative catalysts appear to have been three expatriates who came to live in Oshogbo in the '50s and '60s--a German teacher of English named Ulla Beier, his English artist wife, Georgina, and an Austrian sculptor named Suzanne Wenger, who spent 10 years working on the Oshun Shrine, a group of buildings and groves of trees set in the bend of a nearby river, where the fertility goddess Oshun was said to reside. Together, they ran workshops and open studios where townspeople were provided with art materials and encouraged to express themselves.

Because nearly everyone in this richly historied corner of Nigeria was already an artisan of one sort or another, some remarkable things happened. This show brings together the work not only of Akanji the bricklayer but also of 10 others who subsequently became well known and showed abroad. Some even received commissions to decorate public and private buildings and shrines: Akanji, who worked for years on the Oshun shrine, did the facade of an Esso station pictured here, as well as the aforementioned four-panel screen commissioned by Waldemar A. Nielsen, a past president of the Africa America Institute.

For 20 years this screen had been visible to anyone who passed the garden wall of Nielsen's Upper East Side Manhattan home. And there it stood, crumbling from the ravages of weather and time, until it was donated to the museum in 1994. The conservation job took 1,000 hours over nine months, "much more than we'd expected," said Stephen Mellor, who headed the museum's conservation team.

Today, fully repaired and reinforced from behind by steel brackets, it looks as good as new. "We're hoping this will make clear to other collectors how interested we are in acquiring art from this period," said Bryna Freyer, who curated the show jointly with Andrea Nicolls.

Akanji's subject matter, like that of many artists here, is a whimsical combination of contemporary and traditional elements. Cars and other modes of transport, flattened into diagrammatic linear forms, figure prominently: One figure rides a donkey, another a motorbike. A man fills his car with gas while below a woman dances to the beat of a tribal drum, the edge of her skirt defined by a rhythmic, undulating line--not the sort of lilting form we usually associate with concrete.

Other artists represented here were equally inventive in other media: Muraina Oyelami made yarn paintings; Jimoh Buraimoh updated a traditional Yoruba medium--glass beads--by combining them with ceramic tile to produce mosaic plaques, tables and stools. Twins Seven-Seven, perhaps the best-known artist here, not only paints but is a composer and musician who has produced several records and CDs abroad, including "Nigeria Beat" in 1989. Happily, earphones have been installed so we can hear his music.

But the most endearing artist here is Asiru Olatunde (1918-93), a blacksmith. Forced by illness to give up strenuous work, he began hammering recycled sheets of brass and aluminum, producing enchanting relief narratives that vividly depict Yoruba tales from the oral tradition. Often centered on a tree of life, and incorporating lions, snakes and birds in bold but always tender compositions, his works have the charm of a peaceable kingdom.

But they are poignant, too--especially his depiction of the well-known Yoruba story, "Woman With Four Breasts." It is the story of a princess born with this affliction, whose father was ashamed of her. She left home and met and married a hunter who agreed not to ridicule her, but ultimately did. Returning to her father, she found she was still unaccepted. In the end, she went into the bush and "became a river"--something the artist imaginatively depicts in a way that suggests she may have drowned herself. Discovering her transformation, her father rejoiced. I'm not sure what this story once meant, but in this post-Freudian age you end up hating the father but loving the artist for his sweet rendition of the story.

The installation of this exhibition is confusing, leaving viewers not only uncertain where to look next, but also unclear about which artist created which work, since the artists' names have been omitted from the labels beside each work. (Museum officials concede the problem and say labels will be redone.) More consideration seems to have been given to other educational aspects of this show, including a helpful section on the restoration of the Akanji screens, a video documentary featuring many of the artists, and a reading area with sofas, where publications on contemporary Nigerian art are available for perusing. Other events, including lectures, a panel discussion, musical programs and a children's workshop, are in the works. For details, call 202-357-4600, Ext. 221. A free brochure has been published.

Though the show fails to do so, visitors can provide themselves with some interesting historical context by crossing the central hall to the galleries containing traditional Yoruba art, including some extraordinary beadwork and two magnificent wooden doors with narrative relief carvings that provide a backdrop and basis for comparison with these works from the '60s. The show will continue through Oct. 22 in the Sylvia H. Williams Gallery.

'A CONCRETE VISION'

"A Concrete Vision: Oshogbo Art in the 1960s" opens today and continues through Oct. 22. The National Museum of African Art is located at 950 Independence Ave. SW (Smithsonian Metro stop) and is open from 10 a.m. to 5:30 p.m. daily. Admission is free.

The museum's education department is offering several related events, including a lecture at 2 p.m. Saturday by Victoria Scott, a specialist in the Oshogbo school. Titled "Reminiscing About an African Renaissance: Oshogbo in the 1970s," it will take place in the museum's lecture hall.

Talks in the gallery by co-curators Andrea Nicolls and Bryna Freyer will be held, respectively, today and next Sunday at 2 p.m. For information on related programs, including music, film and children's workshops, call 202-357-4600, Ext. 221.