No the kids are not idiots.. they're naïve.  They believe what the teachers tell them because teachers know everything. That's why they're teachers.

That's where you as a parent/grandparent/uncle/what ever needs to step up and explain how the world works. Those in power try to indoctrinate those under their power to their way of thinking and believing. Teach them to think for themselves and not blindly trust what they are being told.  If the mushers would have done this they wouldn't have been suckered into participating in a movie.

Naivety is the problem not stupidity. They can learn to think for themselves if taught to do it.