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[quote]
Is there a list of classes you can sit in on or do you try to find classes on your own? How structured is this?
[/quote]
You may be given a list, but I don't remember. Students are welcome to sit in on almost any class (though if it's a small, discussion type class, rather than a lecture, they should arrive early and ask the professor for permission first - as a courtesy - professors will almost univerally welcome you). If you want a complete listing of Yale classes, go to <a href="http://students.yale.edu/oci/search.jsp%5B/url%5D">http://students.yale.edu/oci/search.jsp</a> (I think you can access it, since I don't have to log-in to reach it). You can use it to search for classes by department, date and time, professor, etc. It's a really useful tool to find a class you're interested in.
Also, students at Bulldog Days will often end up attending one of their host's or host's friends' classes that sounds interesting, so there's no need to find something in advance.</p>