My daughter is a Rice freshman with anxiety disorder incl. panic attacks, and this statement applies to her verbatim, so we have given a lot of thought to this exact issue. I will say that O-week is pretty overwhelming, but my daughter’s O-week student leaders were super-understanding and went above and beyond to accommodate her need for some quiet and downtime amidst the nonstop activities - they even went line-by-line through the schedule to identify potentially problematic activities (surprise fireworks?!?!?) and suggest break times and skippable events, which really helped. There are a lot of neuro-divergent students, so it definitely wasn’t the first time that such a request had been made. I’m told there’s a movement afoot to modify O-week by relaxing the schedule, but in the meantime accommodations are available if you ask.
As far as Beer Bike, it’s in the spring so no experience yet, but realize that the participants these days drink water, not beer. There are surely other parties that go on around the event and beer is undoubtedly consumed there, but in general, Rice has been very comfortable for my non-substance-using kid. She has been around kids who were drinking, smoking, etc. on a few occasions, but has never felt any pressure to partake and in fact has been told by the student leaders of her college that any kind of social pressure to do anything one isn’t comfortable with is unacceptable. She’s found that to be absolutely true. There are periodic campus-wide parties sponsored by each of the 11 colleges in turn, and my daughter says they vary in quality; some are basically just drinking and loud music, which she just skips, and some have quirky/artsy/low-key activities that she enjoys like face painting and temporary tattoos and cornhole etc.etc. On the whole, she’s a big fan of Rice, and I wouldn’t strike it from the list for an introverted kid just based on the social scene.