When does a hobby become a extracurricular?

Answered

To me, two major things stand out.

1) If you have some achievement you've achieved while participating in the hobby, and

2) How much you've grown as a person from the aforementioned hobby.

I like to roller skate outside of school and am currently fast enough to join that rink's speed team as a beginner. However, the time commitment is too great for me to do so, meaning I cannot join the team or get any awards. I would recommend you mention the activity if you have gotten awards for it which may actually mean something, especially if your extracurricular activities may be lacking.

The second major point is whether or not the activity has helped you grow as a person. I did volleyball at my school for two years and I don't mention it in any EC section these days because it truly did not have much of an impact on me. I am more inclined to write about roller skating for a college essay because that had a significant impact on me and gives me something that I can write about. If the activity helped you grow as a person, I recommend you find a way to bring it up in essays or interviews as a way for the admissions team to see your whole person, but it may be a little risky to just put the activity in ECs if you have other ECs or awards more deserving of that spot. (For example, I myself have awards/honors/ECs that I would much rather put in the EC/awards section of applications because they may be actual honors or be exclusively through school, etc. I can still incorporate roller skating into an essay, but that may be its best spot.) When it comes to essays, the topic doesn't necessarily trump style. Just because you flew across the world doesn't mean you get into a school and the kid who wrote about biking doesn't. Style is often more important because it emphasizes your voice, so write about something that means something to you. And if that includes an activity, that will be your best bet.

Hope this helps! :)