Fanclubs in Japan
 

Are there really fanclubs (like for guys that girls think are attractive) such as the Yuki fanclub?

Where did the fanclub idea come from? Did it originate from some sort of anime or start in Japanese culture? Or from anime fans to be copied into the anime? We've never had anything like a fanclub in the schools I've attended in the U.S.

Although I'm not certain and my opinion is pretty much baseless, I doubt the fan club idea originated in Japan. I think the name itself is a great indication of where it might have originated from.

You can find fan clubs all around America, at least. It's a large thing in the West. They're normally directed towards celebrities, books, writers and so on. Of course, the meaning can stretch deeper than this if stripped from the term "fan club." Anyways, the whole idea of forming a fan club for a specific and publicly unknown individual in a scholastic setting is probably Japan's adaptation of the concept. I doubt people in the west would group together to admire a fellow peer/colleague. I think they'd rather make "private" advances towards those individuals or just come to mutual agreements in conversations and leave it at that.

Don't take my word for it though.
Wait for someone with a deeper understanding of Japanese culture to explain this to you.