Translation:What time do you finish school?
I wrote "What time are you let out of school?" and it's wrong. It's just another way of saying it! And I'm Chinese too!
"What time are you dismissed from school" should also be accepted...
English is misleading you. We use "school" to mean both the place and, in phrases like this, to mean the students' classes. But we're not asking here when the school building will finish, we're asking when classes finish. 学校 is the place, so not used in this sentence.
But 学 isn't really on its own here; it's used as part of the word 放学 which means to finish classes, get out of school for the day, etc.