History as lived time
The kids experience history in a new way when they find themselves teleported back to feudal France. They realize that the history they learned about in books is real time, as real as their own waking consciousness in present day. This adds a new dimension to their experience of their own knowledge, because for some reason, before they had to live it, they only understood history in a hypothetical way, but in light of this novel's plot, they realize that they had drastically underestimated the drama and value of history.
Picking teams
When they arrive back in time, they realize that it isn't as easy as they expected to pick a side. First of all, they have no context to judge the two sides. Who has the right? Paris or the Viking invasion? They try to use their moral judgment, but the dilemma is far beyond the domain of their life experience. All they know is that they are scared of getting caught on the losing side, so there is some lesson there about quickly judging people in history—because in their own experience, their modern insight doesn't apply.
War and peace
Something is clear to the children. War in this situation would be an absolute nightmare. This is also a lesson about how they view history. Through school, kids have to learn about human history, but they learn about it from a young age, and by the time they're old enough to have a grasp on what has happened, they are often desensitized. They read about wars every day, each war becoming a few chapters in a textbook, but not in this novel. In this novel, the children are horrified by the chances of war and death. The value of war is more adequately assessed.
