I'm going to leg-sweep my classmate
What is your reason for wanting to leg-sweep your classmate?
Do you have any suggestions what to do if someone doesn't want to let you pass?
Frankly, I'd suggest you be patient.  You shouldn't just hurt others because you're unhappy with a situation.
I'm not going to listen, I'm going to leg-sweep him.
This is not going to do any good whatsoever for this situation. If the person is still not letting you pass than just try walking past them or letting someone else know. Turning this situation violent is not the way you should go about it.