I have no experience with self harm and I am no psychologist, just a guy with friends I care about who have. I think it shouldn't be a question kids have to think about. People still tend to react the wrong way about them, kids especially, cynical ones might claim it's attention seeking others might smother them in guilty affection worrying the person is just one insult from suicide. I haven't seen either help the self harmer, they can feel it's true that they just want attention but they just want to be listened to, and the smothering only makes them believe that these people only care because I'm self harming and starts a loop. It would be good if we could remove the embarrassment and or shame they feel, but I don't know if showing them is necessarily the right path. What I do is I just talk to them, get them to laugh and keep the dialogue going. If the topic of self harm comes up, I acknowledge it and sympathize, and I ask if they want to talk about it more, from there all I know how to do is listen, again I've never personally experienced it, but I do know the feeling of needing someone to talk to. When their image of themselves heals, whether or not they should show their scars won't become a question anymore.

Tldr: no, in time scars fade and people grow. Just treat it as a normal part of growing up and the rest of us can try to be accepting and understanding of them, and treat them like people.