Back in the olden days (1960s) the expression was "the prom." When (and why) did kids stop going to the prom and start going to prom?
i noticed the diff too, and am not sure when that happened. but what’s really hilarious is my 89 yo FIL who has clearly forgotten what PROM is, bc xshub told his dad that xsjr was going to prom, and he sent her $400 saying how proud he was of her “making prom” and that he knows how hard she works, and that mommy and daddy are very proud of her too. he clearly thinks it’s some academic honor she has acheived! we have been roaring about that all week!