I went to high school in Idaho (decades ago) and there is something to that. Idaho does not have some of the problems that other states with larger, more diverse populations have. If most students belong to any culture, whatever that culture is, there may be less conflict. Because Idaho is mostly rural and small towns, they don't have some of the problems of dense urban areas.
Mormon culture conditions people to be compliant to authority, and they have a lot of practice sitting down and shutting up. That could make things easy for a teacher.
This is not to say that Idaho does not have its own challenges, like any place, but it makes sense that any given teacher might consider Idaho an "easier" place to teach.