Children re-enact what they are watching.
Observe your children, if you show them Dora, they will certainly play Dora after screening it.
If you show them Cow-boys and indians, they will play those... etc...
That is why it is so important to choose carefully which programs you are showing to them. In a collectivity, if you show children scary or violent programs, it will excite them. And I do consider some classics to be violent and scary, most Disney are!
Seeing Bambi loose his mother or Dumbo being so badly treated, makes many children uncomfortable (a very healthy reaction of course). They will have to expel those feeling by acting up. It is a natural way to "digest" those images.
If the collectivity, let's say, a school, for example, because it is raining outside, show a positive program, one with only good message and no scary images. You can be sure that the children will feel good after screening it, and certainly re-enact those good images.
Mary Poppins is a good example. It suggests great ideas and good feelings.
I believe that no collectivity and particularly school should ever show programs with a violent or scary side. Plus, considering that most of the children in America are watching too much TV and movies already at home, and certainly not much documentaries, school seems to be the best place to show them great documentaries which help them discover new facts and probably make them think about the subject, eventually speak about it with their teacher after.