Summer and spring are the best times to clean out and move things around at home . . . and in the gallery, it seems.

The National Museum of African Art, for example, closes its Capitol Hill doors next month for its move to the new Smithsonian Quadrangle complex being built at 950 Independence Ave. SW. The Folger Shakespeare Library is also doing some reshuffling. Its Great Hall exhibition space will be closed from July through September.

Artifacts will be on display at the African museum until June 15 (its special show on Bamana figurative sculpture is reviewed at left). Then the collection, which has been housed in the cluster of town houses on A Street NE since 1964, will be put in storage, where it will remain for a few months until the move into the new building begins in August. The collection's new home, the Quadrangle complex, opens in June 1987.

Part of the space problem at the museum's Capitol Hill location has to do with the nature of its collection. Its 16,000 items from sub-Saharan Africa are, for the most part, three-dimensional and therefore more difficult to store than flat works. Those items -- works in gold, wood, ivory and some textiles -- are stored at the museum and in the Smithsonian's Silver Hill storage facility. A 10,000-volume library and an extensive photo archive are also part of the collection.

Most of the African museum's art dates from the 19th and 20th centuries, which is "what most collections of African art are," says museum spokeswoman Margaret Bertin. "A few things go back to 15th and 16th century," she says.

Bertin says that three big exhibits have been lined up for the museum's debut year in the Quadrangle: "African Art and the Cycle of Life," 150 objects "culled from some of the best collections all over the world"; "West African Textiles and the Birth of Royal Kente," a show about weaving traditions among West African tribes, like the Ashanti; and a show of selections from the permanent collection.

The Folger, meanwhile, will begin initial renovation of its Great Hall with a $250,000 challenge grant from the Mable Pew Myrin Charitable Trust, a $250,000 grant from the Kresge Foundation and $50,000 it has raised in smaller donations. The library's renovation fund-raising goal is $900,000.

Few think of the Folger as a place to see exhibitions; the way things stand now, few would want to bother. Its antiquated display cases in the Great Hall date from the building's construction in 1932. The paintings of Shakespearean scenes are difficult to see because the lighting is poor.

But after renovation, the Folger intends to dust off much of its collection for public viewing, including some of its First Folio editions of Shakespeare -- the Folger has 79 of the 240 extant. It also has the largest collection of paintings on Shakespearean subjects in the United States, few of which can now be shown, including 18th- and 19th-century Shakespearean scenes by Henry Fuseli, George Romney and Benjamin West. New cases also will be installed for the Folger's collection of Renaissance volumes on history, science and economics.

And, the renovations promise more interesting exhibits -- heretofore unthinkable. The first such exhibit, "Time: The Great Innovator," opening Oct. 1, will detail the history of timekeeping and time consciousness in early modern Europe. Books about time will be displayed, along with documents related to calendar reform, and a selection of clocks from the Rockford, Ill., Time Museum.

Octagon Museum Restoration

If you see people going in the back door of the American Institute of Architects' Octagon Museum, don't be alarmed. They'll just be avoiding restoration work in the front of the building. This summer, the museum's stone portico will be restored and repainted, courtesy of a $5,000 grant from the Paris-based Association des Vieilles Maisons Francaises. It's really, "a kickoff for an extensive exterior restoration" that is planned for the building, says curator Nancy Davis.

Arts, Etc.

The Northern Virginia Youth Symphony heads south to the 10th annual Spoleto Festival in Charleston, S.C., where it will perform May 29-30 . . . Friends of the Nancy Hanks Center, an organization formed to commemorate the late popular chairman of the National Endowment for the Arts, received $50,000 from the Samuel I. Newhouse Foundation; the Friends plan to use the money for a film about Hanks' fight that saved the Old Post Office, and an oral history of her life . . . The Washington Chamber Society will dedicate the proceeds of its last concert of the season, May 25 at the Performing Arts Center of the Montgomery College Rockville Campus, to the Mental Health Association of Montgomery County . . . Art historian Richard Rosenblum has joined the Hirshhorn Museum and Sculpture Garden board of trustees.