As I'm growing old and studying history books more often, I've came to the conclusion that the problem with the history classes that I had when I was young, is that they were just like fairy tales. What I mean, is that theses classes were given given by the teachers like someone telling a fairy tale, the teacher never explain how he/she knew all those facts about historical events, and the students never asked.
In my humble opinion the schools should start to teach the students the basic concepts of historiography and the scientific method. Only after learn how to judge the evidences about the facts that they are told in class, they could learn to see history and all other subjects, as a topic open to criticism and revision. Every branch of knowledge require of those who really want to learn it, to understand the scientific method and in what kind of evidence is used as the metaphysical base of knowledge.
Unfortunately, our educational system reserved this kind of knowledge only for university students, which is absurd, because in order to really learn something, you need to be able to question your teachers.