Vashti and the Strange God by Gladys Moon Cook

Vashti was barely a teenager, but she had already seen life at its worst. Then suddenly, it seemed that the gods were offering her the best gift imaginable---a chance to attend boarding school, far fromt he life she hated.

But school brought problems and questions. Who was this Jesus Christ, anyway? What power did He hold over Christians? No one forced her to worship Him. No one tried to destroy her Hindu faith. But she couldn't ignore the claims of this strange God.