There is always a balance between concealability, accessibility and effectiveness of the firearm to be carried. The pocket holster probably prints the least but might be difficult to access while seated, as would a way-inside-the-pants style. Inside the shirt would be slow or impossible depending on your style of dress. Perhaps a good option is a belt holster that looks like a phone case? Everyone at college has a phone and you would look no different
. Good luck in your decision.