"Google does not have specific eligibility requirements for mentors, as we know our mentoring organizations will be best able to determine the selection criteria for their mentors."
I don't know if LispNYC has any specific requirements.
As a mentor, I think you have to be in email contact with your student, give them advice as necessary, and evaluate their work. I believe I read somewhere that they estimate mentoring will take about 5 hours a week depending on the number and difficulty of projects.
If there's no need to be physically there, I'm willing to mentor you, in case sacado is somehow disqualified or is otherwise unable to mentor you (I'll probably ask sacado to unofficially mentor my mentoring you, though, sort of a meta-mentor). Anyway I've just applied, although I'll gladly defer to sacado (it'll be mostly his code anyway) if he is able to mentor you.
Note that due to various circumstances, I won't be able to leave my country until about a year or so, so if my physical presence is needed, sorry!