When "Vanities" first unfolded on March 22, 1976, no one could have guessed that this story of three Texas cheerleaders would break records and become the longest running off-Broadway play. Still going strong at the Chelsea Theater Center in New York, it is also turning up at the Publick Playhouse this weekend in a first-rate production by the University of Maryland theater department.

The strength of "Vanities" lies in the tight, skillful writing of Jack Heifner, who has a gift for sharp characterization and telling lines. Sometimes the play seems almost too well crafted and the structure too neat, but Heifner manages to save himself from artificiality through his sure grasp of human nature.

The three pretty, popular girls are vividly drawn, retaining, even in their most ridiculous moments, a three-dimensional quality that makes the audience care about them. With deft humor and understated irony, Heifner traces their development from high school cheerleading to sorority life to adulthood. Spanning the years from 1963 to 1974, the story of their maturing is also the story of America's coming of age through the Vietnam war and the assassination of John F. Kennedy.

Karen Gail Kessler, Kathryn Silvia and Cheryl Ann Aiello do a splendid job with their roles, playing off each other with snap and sparkle. Ideally, the final scene should have a more intense undertone to stress the play's bittersweet quality -- Joanne's flutteriness needs a more desperate edge, Kathy's maturity could be tougher, Sarah's realism could sound a harder note -- but the evening's overall thrust is excellent.

William Patterson's direction is well paced to convey the girls' transition from breathless youth to clear-eyed adulthood. The set is simple and effective and the costumes delightfully accurate.

For ticket information on "Vanities," which starts at 8 tomorrow night and Saturday at the Publick Playhouse in Cheverly, call 277-1710.