I read the story in the early 2000s, and the story was about a strange girl and a nerd who were preparing to attend a prom. In the prom, "the elder or future graduates" would travel from the future to 'chat' with the younger graduate. But the time travelers can not speak, so that they would write something down to show their future lives. In the story, the nerd became a professor in the future. But the strange girl had received a notes from the future one, which says something like 'you are not being bored'. I really love this short story, but I can't find it. If anyone can identify for me the author and title of this story, I would really appreciate it.
I believe this is The Nostalginauts by S.N. Dyer, published in Asimov's March 1997 edition and republished in Year’s Best SF 3, edited by David G. Hartwell (1998). There's a free audio version here:
When time travelers first started showing up they were called phantoms. When scientists figured out what they were, the media called them time tourists, or nostalginauts. We stuck with phantom, pronounced phan-dumb, and finally just dumdums.
I mean, what a phenomenally stupid invention. Time travel that only takes you twenty-five years into the past, lasts half a minute, and you’re insubstantial too. It makes a quest for rubber beverage containers look intelligent.
And, the ending:
But I still had my patented sardonic grin, as my future self flashed up something white.
“Not pictures,” I moaned.
No. It was an index card. My handwriting didn’t seem to have improved either. I’d scrawled, “IT HASN’T BEEN DULL.”
I shrugged at me and disappeared.
It hasn’t been dull.
Cool. I can live with that.
It was also one of my faves and both it and the title have stuck in my mind.