It teaches you to be a slave to the state. I need school like Alexander the Great had school, from a great teacher; I’m sick and tired of this lousy system to enslave the aspirer.
Then read Aristotle. 
What does school teach? Nothing. You can only learn by applying yourself to what they give you.
Try a “Great Books” college for a liberal arts education. (an education appropriate to a free man)
I know of one which tends to take students who already matriculated at other schools.
mrn
I was told once by a teacher school is good for learning all those facts to kill the boredom with crossword puzzles and trivia games.
It teaches you not to be a whiney bitch.
Pay attention during class, you might yet learn that lesson.
I learnt very, very little at school, except for good technique for learning. Even if the content is dull and the testing method arbitrary, you can’t beat school for learning how to learn.
School shows you the door.
School is supposed to teach the knowledge you need to make it in the world. Whether it accomplishes that is a different story. It does succeed in training the youth to be the pawns of capitalism. Its set up to teach kids to obey their superiors because they are “inferior”.
The subject matter of ‘school’ is all the same: reality. Everything is interesting if you’re wired to comprehend it, its significance, and its relation to the whole of your existence.
It’s on a different forum, but the subject of school came up with discussing data leaks in Austria
While I didn’t try to presented my opinion in as nuanced a form as I do here, it isn’t a philosophy forum after all, I do think that discussion about what school is for, its merits, ect. are potentially interesting.
School is a good place to learn what other people are like and how to survive and thrive with them. It has put me in a million different social situations that I am glad to have seen. With out all the other people I have met… I would have never learned to philosophize.