Personally, I don't think totally like UFOs, a bit more like hermaphrodite cats or four-legged chickens or something. As in, they definitely do exist, and it can be scientifically proven, but nobody really knows why or how common they are, and everyone's got a friend of a friend who's seen one, but...
I was thinking that it would be interesting to have some sort of character fascinated by lore and unique magics trying to fine some legitimate proof of elemental existence and activities. Someone trying to kind of prove that they are not just a fable found in ancient coded writings, but also some real thing that could potentially help or hurt wizarding kind, and doing research to try and further this idea. Picking apart elementals, really, to try to find the true essence of their magic, and see how it differs from "regular" magic.
This would really only be relevant if people didn't really know or believe that elementals were a thing, though, because there is no point in trying to prove the existence of something everyone believes in, though I suppose research could still be done on the subject, and persuasive articles could be written for either side of the debate.
Maybe even trying to create a way for these innate abilities to become learned, or attempt to transform a regular person into an elemental through advanced alchemy and extensive research. Of course this may be impossible, or really, really, realllyy difficult, but that wouldn't necessarily stop a mad scientist from trying.