Coshocton district in Ohio takes part in an unusual experiment that pays students who pass or scores high in the state exams. Pupils here in grades 3 through 6 earn $15 for every "proficient" score and $20 for "accelerated" or "advanced" scores. With annual tests given in five subjects, students can earn up to $100 if they ace their exams. Running counter to decades of research in motivational psychology, the idea of paying students for their test performance is anathema to many educators. Administrators and teachers argue that, in an era when the federal No Child Left Behind Act and other accountability programs are putting unprecedented pressure on schools to show that students' test scores are improving, bold measures are in order. However, the experiment is controversial because some psychological studies suggest that giving students external rewards, such as cash, can extinguish any internal desire to learn for the sheer joy of it. But Eric P. Bettinger, the researcher who heads up Coshocton experiment says whether rewards harm students' motivation, it only depends on who the population is, what the subject is, and how the motivation is. Critics also argue that the experiment is unfair to those who are not chosen to participate. To address this, the schools officials advisory committee agreed to hold a public lottery each year to choose which grades in which schools would participate. Parents, teachers and district officials are hoping that the results of the experiment will be beneficial to all.