[quote=YoshiSkittlez]
it was in Young Justice. No one wanted Cassie in their school because they all knew who she was, and so when they tried to put her into an all girls school the principal wasn't going to let her join because she would be 'a danger' or whatever but then Cissie said that if the principal wouldn't let her in, she was going to quit and the school would no longer have an archer, so the Principal was pretty much black-mailed into letting Cassie in the school and thats how they became friends to start with.
[/quote]

Well Cissie is likely a freshmen at some Star City-relative high school and Roy hasn't even got around to that yet. No idea why Cassie would be in Star.