Magic school, not school of magic?
I must say, as non-native English speaker, I'm confused, it sounds like a mistranslation. I would have thought that in "magic school", magic is short for "magical". At any rate, it should be an adjective.
An English school is not the same as a school of English. The first is a school of English culture while the second is a place where English is taught.
Or am I missing something?