So maybe you say...hey im a girl...no? Too simple? Hhmm

i mean if she can read toughts i guess thats a good way to go about it.

Nah she could have spoken up anytime, at her uniform mistake for example

If you re-read it you will remember that someone recommended her to pass as a boy cause the guy she likes rejects all girls, so it is the only way to try to get closer to him.