The best way to prevent this problem is a two-step approach...
Step 1: Enforce vandalism laws, with heavy fines and penalties for perpetrators, regardless of age.
Step 2: Aggressively paint over or clean graffiti whereven and whenever it is found.
If you raise the cost of graffiti as you lower the reward (because any work completed will be removed within days), idjit kids will soon find another way to waste their time.
Apparently, these kids were well known taggers with “tagger” nicknames and they’d been stopped a week earlier for tagging. The mother knew her kid was doing it, but thought he’d outgrow it. When you’re that stupid, the only thing a brighter headlight would accomplish is to let the engineer get a better look at the kids as the train ran them down.