Rewarding students=better education?

Rewarding students to study is a new way to encourage them to do something they don't really want to.
First of all, the idea that students should be given a prize seems an effective way to avoid absences. Students are atractted by the fact they can have a reward if they go to school. But, that doesn't mean they can pass their exams. It's very possible that, perhaps they go to class only in order to have rewards. And this is another problem:rewards.
Teacher have to think what kind of prizes do attract their students. Because if they don't, students will continue without going to the school. For this reason, the school has to earn money to buy prizes.
So in the end, the idea of rewarding students wouldn't be so great as it seemed at the begining.
Many people think it's a good way to avoid students missing class and others do not think the same, and they believe that students who skip classes do that because they want to, and if someone does really want to study, there would be no need to give any prize.