<p>Does it have to be an organized activity? For example, if I bike ride 4-5 hours a week, does that count as something worth listing on my common app (assuming I have space)? How about reading MAA articles in my free time, etc?</p>
<p>Also, for the extracurricular short response, can it be about an annual one-day event? Or does it have to be about a sustained activity done throughout the year</p>
<p>No, an EC doesn’t have to be organized. It’s anything on which you spend a substantial amount of free time (and presumably want them to know about…) If you are a cyclist, that’s fine. Remember, you don’t want a laundry list of stuff - you want the activities on which you spend a significant part of your time, presumably on an on-going basis. Reading MAA or any other kind of article or book is not a great EC activity by itself because everyone is presumed to read topics of interest to them. But if math is your thing, I assume you have other math related activities that you participate in and reading MAA articles is just part of that? </p>
<p>As for short response, it can be about anything that sheds light on who you are and what you have to offer the school community. An annual one-day event is fine if it’s a significant part of who you are and you participate every year. If it’s a one-shot deal, I’d give it a miss.</p>