Every time she gets on, some boys make oink noises, and no one wants to sit next to her. Making fun of someone because of their appearance is wrong. Oinking noises are based on the stereotype that fat people are messy pigs who eat too much. The fact is that you can't tell how much someone eats just by looking at their size. And being a slob has nothing to do with your size.
Slobs come in all sizes and so do neat, clean people.
Joe is the fattest boy in school. The other kids tease him, so he punches one of them in the arm. He gets sent to the principal's office, but not the other kids. The principal should speak to the kids who were picking on Joe. They need to learn that you can hurt people with words, too.