My sister works in an American school and she has sent me some money as I do not have a job and I desperately need money. Should I take it or refuse? Should she work there anyway?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Originally, the woman should stay at home as Allah orders: {And stay in your houses,} [Quran 33:33]. But it is lawful for her to work in a field that suits her very nature like teaching girls or young boys provided that she leaves home veiled in an Islamic manner and provided that she does not mix with alien men. If she has to mix with alien men, it should be only with a group of people, not alone with one man and she should keep her chastity by not being too complaisant in speech, and by limiting it to the absolute minimum.

Any woman who meets the above conditions may work in such a school. But the woman who fails to comply with the above conditions, commits a sin. The field itself in which she is working is lawful, regardless of her behavior. So, since the work itself is lawful any money coming from it is lawful as well and, any money she gives you from it is lawful to you. But, advise her to work in a place other than these schools as they include a lot of violation to the Sharia like mixing with non-believers and socializing with them which is forbidden and should be avoided completely.

In marriage the husband is responsible for the expenses of his wife.

In this case of being unmarried the guardian of you and your sister, such as father, brother etc. is responsible of spending on you and your sister.

This is a distinguished quality of Islam and it is a simple example of how the woman is honoured in Islam. Islam protects women from being humiliated due to the pressure of poverty and necessity.

If you or your sister could find a job, which fits the nature of the woman, then there is no harm in doing it.

Allah knows best.