A study has found that educational TV shows come with an added lesson that influences the child's behavior. Children who spend more time watching educational programs increase their emotional aggression toward other children. This shows that children can learn the educational lesson that was intended. However, they're also learning other things along the way.
This unintended impact has to do with the portrayal of conflict in media and how preschool-age children comprehend that conflict. TV and movie producers often incorporate an element of bad behavior. This is to teach children a lesson at the end of the program. Educational shows have pro-education and pro-social goals. However, conflict between characters is often depicted with characters being unkind to each other or they may use emotionally aggressive tactics with each other. Preschool children really don't get the moral of the story. That's because it requires that they understand how all the parts of the show fit together. You need pretty complicated cognitive skills and memory skills to be able to do that. These are still developing in young children.
However, parents shouldn't completely constrain children's viewing. Parents should instead watch with their kids and help them to understand the plot. Parents can comment along the way and then explain the message at the end. They should explain how certain types of behavior were not appropriate. This will help children interpret and get the message and help them learn to watch the show for those messages.