We used to dream of smashing up cars with sledgehammers in high school, these kids lived the dream.
No, it's absolutely atrocious that they sprayed such hateful screed on his or her horse.
I certainly do not endorse what they sprayed on the car, but it was just immature and inappropriate behavior and not really much worse. It damaged the reputation of the school and the community, and the kids need to learn a lesson, but it's something I could imagine a lot of bored kids going to a small all-white high school in a small town participating in.
Damn never heard boredom used as an excuse for racism before.