It is indeed half-school half-mental institution.
But I'll be okay. Because I have free will.^_^
Would calling child protective services on the mental institution do anything?
Probably not. There was a big thing about all of the institutions like this awhile ago, and all of those "summer camps for disturbed individuals," or some such. Basically all of those locations either have minimal governmental interference, or pay the judges/parents to send them their disturbed teens for their patented Child Discipline Issues™, or something. They have no oversight, people sign over all of their rights to the schools/camps, and actually treatment/therapy is carried out by untrained and unlicensed "professionals" who "totally know what they're doing." Luckily for them there are giant black holes in our legal system about them, and their word apparently weighs more in court than a "disturbed" teenager's does. Not sure if this institution is exactly like those, but it'd probably be futile to go against it.
Luckily, it sounds like this was a voluntary thing that you could leave at anytime instead of blinding rage-inducing summer camp things they have. If you had videos of the teachers mistreating you, you'd possibly be able to get them on minor assault charges, but the school in general would be protected by claiming ignorance.
Also, I probably blacked out by the sheer amount of rage that I have built up for these "institutions" and shit like this, so if anything doesn't make sense in this post, it's probably because of that.