Adult? Think Laura Ingalls from Little House on the Prairie. These Amish teachers can be 18 year old girls with a GED who never saw the inside of a public school. They aren't 40 year old women with a 4 year college degree. They certainly are sheltered enough to have no experience with evil such as this.
And that is the issue. My wife retired just last August after teaching 27 years. There's no way she would have left the room without the kids. (that's part of why I'm glad she's retired).
These teachers were most likely young... and I didn't always make good decisions when I was young either.