The story about “Wit” is that the play was written by an elementary school teacher. That’s not quite true, scribe Margaret Edson revealed at Thursday’s Broadway opening-night shindig at B.B. King’s. Yes, she’s been an elementary school teacher for 19 years, but she wrote the play 20 years ago — when she worked in a bike shop.

Leading lady Cynthia Nixon arrived at the party with her shaved head on proud display. But as past stars of cancer drama “Wit” know, you can get cold with no hair — which is why Judith Light, who played the part during the show’s original Off Broadway run, gave Nixon a cashmere cap as an opening-night gift.

Nixon recalled that the night before opening, just as the play ended, one theatergoer shouted out, “You’re my girl!” It startled Nixon.

“But it felt very validating,” said the actress. “Sadly, I never got to meet that woman whose girl I am.”