<p>Just join whatever organizations you are interested in. </p>
<p>They don’t care whether you are Barnard or not. They won’t even ask, at least not as a condition for joining. I mean - typically you will find out about an organization and it will be having some sort of meeting – you’ll show up to the meeting. If it is a campus organization, the people at the meeting are just going to assume that everyone there is a student affiliated with Columbia in some way (including Barnard). Depending on how formal the set up is for the organization, at some point you might have to sign some sort of form or roster to become an official member, and that process might entail revealing specifically which school you attend (unless it’s Philolexian Society, in which case you’re kind of stuck being a lifetime member once you’ve shown up to that first meeting).</p>
<p>My guess is that when mysteryflavored showed up to her first marching band meeting, the first question asked was probably “what instrument do you play?” (Or not, as apparently one not actually required to play an “instrument” to be part of the marching band – [Instruments</a> of the Marching Band | Columbia University Marching Band Legacy](<a href=“http://www.cumb.org/instruments/instruments-of-the-marching-band/#more-210]Instruments”>http://www.cumb.org/instruments/instruments-of-the-marching-band/#more-210) )</p>
<p>There is no separation. Really. You can’t be part of Columbia College student government and you can’t join a male-only fraternity … but other than that, it’s really up to you.</p>