Hello,
I'm write you this letter to tell you to keep these graffitis. They are respectfull and I think it's good for all the students to see this every morning, it's less stresfull and the school looks less like a jail. I think every student in this school would agrey with me. I don't think it's a danger or something like that and it's very beautiful. Of course, I'm just a teenager and you can do whatever you want but I think it can be a good idea to keep them.
I hope I convince you,
Goodbye,
Et là tu mets ton nom (relis quand même avant j'ai peut être fait des erreurs)