How you would deal with rampant cheating in school?

First, I prefer to be an Elementary School's principal. Because I think children can be changed easier than adult. When you was born, your mind is clear. You have been learning everything that you have seen at home, at school or in society. As a principal, we have to teach honest behavior at school, also teachers and staff must behave honestly. We can give an open book exam without any stress. If at school, learning is been more important than report card and being first, students can take an exam without cheating. Because I think the most important reason for cheating is good mark.