Would being a part time student adversely affect grad school admissions?
In general, no. But you may want to check out the specific program(s) you're interested in for the admission requirements and a description of how potential candidates are evaluated.
I'm considering top programs in general like MIT and Stanford.
It depends I think. For your masters, probably not. But for your PhD, most schools will allow you to go to school part time to some extent but at some point you will need to be a full time student for a year at least when going for a PhD. Most of my fellow students work full time while going to grad school full time.
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