True story: Curvaceous, young fourth-grade teacher stands at the front of the class reviewing a math problem when she’s interrupted by a snicker, a giggle, and, finally, a raucous hee-haw.

“What’s so funny?” C.Y.T. asks.

The room falls silent. C.Y.T. feels a breeze — and notices the buttons down the front of her shirt have bust open. Literally.

Eliminate such tata tragedies with a shirt from Rebecca & Drew Manufacturing. Their ingenious button-downs are designed according to bra size. (Why didn’t anyone think of this before?)

R&D’s new shop, which opens today in the Meatpacking District, stocks everything from 32A to 38D. The tailored tops are 100 percent cotton and come in short or long sleeve and regular or tall lengths. Choose from lots of fabrics (solids, checks, and plaids) and accents like polka dots and grosgrain trim. As an added safety measure, double buttons prevent unsightly peeping.

Guaranteeing that all your bases — not to mention your boobs — are covered.

Rebecca & Drew Manufacturing, 342 West 13th Street, near Hudson Street (212-647-8904). To see styles, go to rebeccaanddrew.com. To purchase online, go to neimanmarcus.com.