These three guys may be acting in this weird way towards you because there may be something about your body language or appearance that they don’t like. As a result, they feel compelled to bully you.
Yes, you should keep ignoring them.
Don’t make any eye contact with them or show them in any way that you notice what they are doing.
As long as you don’t give them any attention, they may eventually run out of energy and stop acting in this way towards you.
Also, it may be to your benefit to avoid coming across them as much as you can. In other words, perhaps start using different routes to get to where you want to go in your college.
The less they see you, the more likely they will start directing this kind of behavior towards someone else or just stop doing it entirely.