On side of the protesters, i understand making a statement by surrounding the tents that you know are illegally set up and to peacefully defend them and risk arrest to show your determination and seriousness behind your cause. That's honorable, but the events following completely sullied the image of the protest and the credibility of the students, as well as potentially lessening the seriousness of these protests in the eyes of anyone that witnessed the ridiculousness of this event.
Surrounding the cops and making demands? Even then the cops tried to speak to the protesters and warned them multiple times of what they would have to do if the students continued trying to detain them. All they got back were students laughing at them and then making unfounded chants to not fire their guns at them, which is ridiculous. The students obviously played this out like it was some sort of game as you see them often smiling, laughing, and making jokes to the police officers words. The police may have been able to do things more peacefully and not spray the students, but that would of been risky and potentially put the police in danger when looking at the fact that the students would go as far as trying to surround them and make demands. Besides being the safer path, spraying also seems like it was the best option to send an obviously much needed message that these things are no game.
The only way the students actions would have been justified is if the police were unjustly trying to suppress them by disobeying laws or following unjust laws (in which, non-peaceful action would of been called for). -This was not the case, and those students should be ashamed for causing discredit to a meaningful movement.