Seen any strange events popping up in your Facebook News Feed lately?

Maybe something very mundane, like a niche event at a school you've never heard of? Or perhaps something a bit more unusual, like worm-charming or mushroom-growing classes?

Well it's not advertising, and it's not an accident.

It's actually part of what seems to be the latest Facebook trend among British teens: making random events pop up in their friends' News Feeds by saying they're going to attend, even when they're obviously not.

One of the first examples of this was a "Year 10 Parents Evening" in Norwich which ended up going viral in a spectacular way.

Basically every time someone says they're "attending", the event pops up in the News Feeds of their Facebook friends. More and more people jump on the bandwagon, and pretty soon you've got an event with more planned attendees than the maximum capacity of some Premier League games.

There have also been around 3,500 comments in the Discussion for that one, many of which look like this:

The whole thing was so damn popular it even inspired an Oscars-themed meme.

The thing is -- at least in the case of the event above -- it doesn't appear to be real. There are no details tying it to a specific school, and it was posted by a community called WHAT'S ON? NORWICH -- a group created earlier this year that's had a number of other, similar events go viral in much the same way.

In other words, the whole thing likely started as a joke and just happened to go impressively viral.

But the trend is spreading -- and it's now reached plenty of actual, real events too.

Yep -- Blackawton International Festival of Worm Charming is very much a real thing, and while the Facebook group may only have 252 likes, their WormCharing 2017 event now has over 2,400 attendees.

There are plenty more where that came from, too. Among the others we've spotted are viral events about bell-ringing, local coffee meet-and-greets for over 55s, and the following (also real) event at Leeds University Union that teaches people how to grow edible mushrooms at home.

The comments for that last one appear to have been disabled, unsurprisingly.

At the time of writing, we don't know what the event organisers think about all this. Mashablehas reached out to the people behind both the Worm Charming event and the mushroom growing introduction, and we will update this article if we receive a response.

One thing is clear, however -- this trend doesn't seem to be going anywhere anytime soon.