*Forget about you, one of those guys might also feel uncomfortable helping a girl 🙂
If you ask for help in front of others(the frum boys as a group, usually they hang out together) instead of just one on one you will not come across as it being a boy girl thing, or that your interested in one specific guy
however with your concerns.
It depends also on a) what a few questions are. math problems have to be explained usually and this could take some time a person will probably have to help you a bit before or after class Calculus usually cannot be mastered over a five minute class break.If you feel you need extensive help depending on how important your grade is you might want to get a tutor beside help from classmates.
b) if any of the frum guys are married, their wives might not appreciate them helping you long term one on one in such a casual atmosphere, while college is like a workplace it is much more casual.(requests of others in the workplace are an accepted norm,I assume in a workplace you would not hesitate to ask the best suited to help you on a project as long as you keep it professional and tznius)
*On the positive,I know of plenty of wonderful shidduchim (yeshivish btw)that came about as a result of being a small frum clique in college you never know if any of these guys have a friend or brother to redt to you.Hatzlacha