What is the ruling regarding a school principal who recently handed over a Muslim female student to Christians out of fear of accountability?

If the student's family learns of her conversion to Islam and their rejection of it, with the possibility of harming her, then the director's action of handing her over to them is a great evil and a grave sin, due to the potential harm that could befall her. The Prophet, peace and blessings be upon him, said: "A Muslim is the brother of a Muslim; he does not oppress him nor does he forsake him." This means not casting him into perdition or leaving him with those who would harm him.

If, in addition to that, the director advised her not to embrace Islam, then that is major disbelief and an apostasy from Islam, because consenting to disbelief is disbelief. And whoever is asked by a disbeliever wishing to embrace Islam to teach him the word of monotheism and does not do so, or advises him not to embrace Islam, or advises a Muslim to apostatize, then he is a disbeliever.

It is obligatory for everyone who knows of this girl's situation to strive to remove injustice from her and enable her to embrace Islam, and to inform the authorities of any harm that may befall her.