Cars scratched by children

My story: My car was scratched the penultimate Saturday, on the passenger side beautiful from the front fender, over the driver’s door further to the back door. On the passenger side the fender was scratched completely on the back right (beautifully in circular movements). So I to the police and a good news: the perpetrators were caught snorted. But there was also bad news: the perpetrators were not They were only 9 years old. By the way, the children scratch 30!!! Cars, Well well. Now I was at the youth court aid (or whatever that means, at least that’s what they’re doing now) and they said that I might stay on the damage. The parents probably don’t stick, and you can’t even get the children. What should I do? Then she said that I should do civil law, only then I get money when the, now 9 years old n, earn money myself. I am a student and I have 500€ for the repair of the damage simply too much! I don’t want to make any money from it, but just have the ugly scratches away. My car only has liability, since it is now already 12 years old. Why is the liability of the parents not liable? Please help me!