Peer editing is important. It is receiving something written by someone your own age. In a younger setting, that can cause a lot of hurt feelings or misunderstandings within the small group. An important aspect not really stressed in the videos was peer editing with a dictionary! Having something there to refer to can dispute arguments and save the stress of guessing one another on spelling or meanings of different words. Good points to make sure to use with students would be to make sure they give a compliment, not just tell them what they did wrong. Compliments tell the writer what they did right and gives them a good feeling about their work, instead of just criticism.
Gentle criticism is important for students to learn what they do wrong while not crushing what they think about their work. If a student comes to peer editing with a work they think the world of, but it is not what they think it is, it's very important not to step on toes and hurt feelings. Constructive criticism is the best way to get around that and teaching people at a young age how to positively edit someone's work is the best way to do it. Teaching children at a young age to peer edit will be helpful to them through everything they do, even if it's something bigger than a paper. Peer editing will be used for your entire life, it's best to be done correctly and nicely while still giving structure to what needs to be fixed.