Incentives and Senioritis

The movie suggested that human nature is to work for the sake of earning incentives.  The movie introduced the idea of paying 9th graders for getting good grades as a for of incentives for hard work.  The incentive of money, however, seemed to be fairly ineffective for one student even if it worked for another.  Although one kid really liked the idea of winning, getting driven home in a limousine, etc. the other did not find the incentive to be enough to work towards the goal.  Its possible that for him the goal was too high, as he appeared to be fully intent of waiting until he got kicked out of school to join the army.  It seems to me that the reward should have applied to someone raising their grade in general, not for hitting a predetermined benchmark.  Furthermore, I do not think that the incentive of money was enough for all of the students.  Like the failing student said, he wanted to be the class clown and be social in high school.  A better incentive would have been if his friends thought better of him for doing well in school, or if he had to achieve a certain level of grades to hang out with them as often.  In this specific scenario, I think that we would have to examine the work and rewards of each individual student in order to get the best result, which suggests that this type of work falls to the parents, not the school.