Good for you for standing up against your system. Never feel ashamed to question conventional wisdom. Those that use physical abuse to discipline unruly children do so more out of frustration than with the intent of bettering the child's behavior. It's a momentary patch with unintended consequences further down the road. I would agree that corporal punishment is the last (and sometimes only) resort to those in charge who aren't equipped to handle the situation at hand. Again, more often than not, it's a lashing-out of frustration that creates a cycle of abuse and an expectation that such behavior (physical abuse) is appropriate during periods of mental or emotional frustration.
What I would do in your position is the following...
These sorts of things are identical in circumstance to war, so read war strategies such as the 48 Laws of Power, the Art of War, etc. Don't rush into any sort of confrontation because it is highly likely you are entirely unprepared. Going against an established institution that is prepared to handle uprising or discent is a big mistake, you will be struck down quickly. It's always the first rule to know your enemy (not identify, but strengths, weaknesses, capability, scope of influence, etc).
You would be well suited to recruit your 30 friends and hold a meeting in which you all agree to purchase a video camera. Record any and all demonstrations of abuse, and keep these records safe. Develop a website (as mentioned), where you would archive this material. Next round of tuition payment, record your encounter for proof of cash requirements. Visit forums that have users in your area, adult users. Find like-minded adults that are willing to co-sign your cause to lend clout of maturity, so you won't appear as whiny adolescents that should be ignored. Your videos will go a long way in building a community of support among like-minded adults. Once you have everything aligned, begin your public campaign using strategies already mentioned such as public speaking, circulating leaflets/fliers, driving traffic to your website, etc. Equip your site w/ features that are conducive to virality such as sharing.
Good luck.