An item in yesterday's Theater Notes column incorrectly stated that the Folger Theater had shut down for the summer.The Folger's production of "As You Like It" will continue through July 15.

Theater tends to abscond from Washington every year about now, but this year's dearth may be worse than usual.

Not only have Arena Stage, the Folger Shakespare Theater and Ford's Theater all suspended operations until September, but the National, too, will be dark as a result of a last -- minute cancellation. The Lawrence Roman play "If If If" that was scheduled to bring Dick Van Dyke back to the stage for the first time in 19 years, will skip Washington and go directly to New York, according to its producers, the Theater Guild.

The guild explains that "the physical complexities of the production, with its many flashbacks and dream sequences, would make it impossible to have sets and lighting designed, constructed and installed by July 17, when the play was scheduled to begin performances in Washington."

An additional detail, not mentioned by the Theater Guild in its official announcement, was the withdrawal of a key investor.

Thus the National, which has seen its share of hard times, is left without an attraction for the remainder of the summer. [The muscial "Daddy Goodness" is scheduled to arrive in September.]

And even the Eisenhower, empty for only a cumulative two weeks since its opening in 1971, according to the Kennedy Center's Leo Sullivan, will be dark until Ira Levin's "Death Trap" begins performances there on July 24. The revival of Somerset Maugham's "Home and Beauty" was terminated last week because of poor ticket sales.

But Shakespare has not forsaken the Mall.

"I have been scorging around and getting some money," says Ellie Chamberlain, whose Shakespare Summer Festival will once again offer free performances -- this year of "The Taming of the Shrew" -- at the Sylvan Theater on the Washington Monument grounds.

The play will commence next Thursday, July 12, and continue through the 21st.

Nevertheless, says Chamberlain, the budget has gaps that need filling. Contributions may be sent to Shakespare Summer Festival, 1000 Sixth Street SW, Washington, D.C. 20024.

The Prince George's Country Department of Parks and Recreation and the Public Playhouse will offer a joint seminar on stage lighting on Saturday, Aug. 4, and again Aug. 11. The seminars will be held at the playhouse, at the intersection of Landover and Annapolis Roads in Cheverly. For information, call 277-1711.

The Theatre Schools, 306 H St. NW, is offering summer courses for the first time in acting, voice, makeup and a general "introduction to the theatre." Call 789-1813 for information.

The University of Maryland's theatre faculty will offer Creative Dramatics classes for children starting July 24. Call 454-2541.