Yes, it's my understanding that is why there is a window in the door or a window by the door in classrooms. The idea behind it was to ensure safety of children so that someone else could see in and know what was going on inside the classroom.
After Columbine I covered my window with the colored roll paper. It certainly would stop any bullets. Not, but I did not want a shooter looking in my window.
Sexual abuse issues are huge for teachers. Where I live, if you are accused, you are immediately removed from your job until proven innocent.
This happened to a teacher that was falsely accused, not by a student, but in another situation. She was exonerated, but life was made so miserable for her that she quit her job.
Being a teacher is filled with so many issues.