Don't Call Me Master, I'm Just a Teacher

In the world Victor Kyle wakes up in, a person's standing is decided by the gift they are born with, and he arrives with none. To everyone around him he is a bottom-ranked teacher, a man with no magic and no connections. What they do not know is that he is a physics professor from Earth. He is also bound to something called the Teacher Cashback System. It will send him home once he has collected 999 gifts, and there is no other route back. He takes the students who have been written off as trash and trains them with Earth physics, finding another way around. They turn into strong gifted users. Old rivals who resent anyone abler than themselves come at him repeatedly and lose face each time. Over time his teaching, built on Earth's knowledge, spreads beyond his own classroom and begins to rebuild the gift system itself on physics.