No question about it: Alternative spaces like the Washington Project for the Arts are turning out to be some of the best alternatives in town.

Last night there was a celebration to mark the opening of a new exhibition at the WPA, as well as two new nearby outdoor sculpture projects by Nade Haley and Jim Sanborn. Director Al Nodal revealed that WPA is about to acquire, from the Department of Housing, additional storefront space next door to the existing G Street gallery, to be used for an artists' annex -- a truly artist-run situation.

WPA's new exhibition, "Stacking/Rigging/Binding: 10 Contemporary Sculptors," is an example of the kinds of alternatives that WPA can provide. The show is both too experimental and too ambitious to turn up either in a museum or in a commercial gallery here.

Happily, Howard Fox, the imaginative Hirshhorn curator who organized that museum's landmark new "Directions" show last year, was willing to serve as guest curator for this sequel at WPA. "I felt there were further ideas suggested by the "Directions" show that I wanted the chance to explore," says Fox.

"This is an exhibition about tensions," he says, noting that all the constructions are either rigged to hang from the ceiling, pressed against the walls or stacked -- sometimes perilously -- from the floor upward. Thomas Watcke's room-installation, "Unit Work 5x5," for example, arouses tension in the viewer, who instinctively fears that these leaning stacks of two-by-fours will come tumbling down. Other works by Watcke deal with another kind of stress: the kind that comes from taxing the materials nearly to the breaking point. These are wood pieces created by making incisions with a band-saw into a large solid square column of wood, and then stretching the block open like so many paper cutouts. The result is amazing.

"These are not just pieces, but verge on being events," says Fox, and indeed one very big event here is a mine-boggling maze, or labyrinth, made entirely of stacked wood lath, that seems to go on forever as the viewer walks through it. The artist, Edward Mayer in this "Spiral with 2 Triangles," engages the viewer by making him move through the piece and participate in it, arousing both a sense of wonder and a touch of fear of entrapment. This is a new kind of "content" for sculpture, notes Fox, involving not only the look of something, but the experience of how it feels, and how it makes us behave.

There is more: handsome stacked sandstone pieces by Jim Sanborn, shown earlier this year at Diane Brown; and "Typhoon," a piece made from sails by Patrick Mohr, whose similar work on the WPA's facade tore itself to bits during a recent rainstorm. Loren Madsen has sent a maquette for an intriguing circular piece made of 12-by-12 inch square timbers that lean on each other, while Arthur Weyhe crosses Kenneth Snelson with Mark di Suvero and comes up with some rather derivative white cedar-rope-and-pulley pieces. Bruce Chao's installation of suspended panes of glass has virtually no meaning, and though newcomer Renee Butler illustrates stress by placing a rock in a sling of cheesecloth, that's about it.

Once at the WPA, it would be a mistake to miss the outdoor works. At the corner of 12th and G, Nade Haley has installed a handsome, swooping series of curves constructed of wood, titled "Overture: G-Strings." The piece has some problems, notably the rather awkward configuration of the rear segment, but her talent shines through. Half a block away, at 1109 G St., James Sanborn has just created what amounts to a brand new vestpocket park, a cool, center-city oasis -- made of scattered stones and bits of copper, sulphur and sand -- that lead right up to a real live pool. Titled "Fire, Brimstone and the Great Salt Lake," the work celebrates, Sanborn says, the unification of art and geology.

By the way, one of Jon Petersen's "Bum Shelters" can be observed diagonally across from the Haley piece.

Paul VI, one of the area's most unusual galleries, is devoted to exhibiting and selling art that has spiritual content but is not necessarily "church" art.

"We try to avoid the pious," says Rev. Michael F. Farina, a Roman Catholic priest who is also the gallery director. The gallery is ecumenical: cIts first show in 1977 featured spiritual themes by Jewish artists, including Abraham Rattner, Leonard Baskin, Jack Levine, Ben Shahn and Joseph Hirsch.

After three years in Alexandria, the gallery is now in a new location just off Route 5 and Suitland Parkway at 3720A Old Silver Hill Road, Silver Hill, Md. It will continue to show a wide range of work, from sculpture and prints by well-known artists like Baskin to cloisonne by Sister Lucinda Hubing from Milwaukee, and canvases with cloth collage by Tatina McKinney, whose "Resurrection" is in the pope's private collection.

"We try to peddle our artists to the Vatican collections," confesses Father Farina, who also occasionally arranges shows at the Apostolic Delegation here. "We've done well with the clergy, leading them to greener pastures." The gallery has arranged commissions for several of its artists, both in churches and other public spaces.

Currently on view is a group exhibition by gallery artists, among them figurative bronze sculptors Barry Johnson, Judith Brown and Elizabeth Kormendy (one of the gallery founders) still-life painter Robert White, collagist Douglas Hendershot, printmaker Robert Enos and the young Peruvian-born painter Yoli.

"You can't ask people to make art with spiritual content and not offer them an outlet," says Father Farina. The Gallery is a project of the Institute for the Arts of the Archdiocese of Washington, and is open Tuesday through Saturday, 10 to 5.