If a child comes home with teeth marks from another child, esp if it happens more than once and/or it breaks the skin, the parents CAN insist the police file charges of assault against the other child. Just because it happens at school does NOT mean parents have to let school deal with it. Some would let school deal with it the first time, some won't do that.
It worked in OH when one kid first stabbed Wiz in the arm with a pencil, and Wiz was NOT a problem in the class at daycare at that time, not EVER (that came later). The other boy would just roam around the room hurting one kid after another - tackling with no warning from behind, biting, stabbing iwth anything at hand (he broke the skin on a child's arm with a CRAYON at one point. A regular, crayola type crayon. This is how violent he was. they said they couldn't kick him out because he had a voucher from social services to pay for daycare. I called BS and the cops because NO ONE assaulted my five yo child repeatedly with no consequences. They did go to the daycare and said that either they kept Wiz and the other kids safe or got rid of the dangerous kid or the child's parents would face the judge and so would the adults running the daycare. NOT just the teacher or head of the daycare, they would ALL be cited and taken in front of the judge.
Here, when a boy kept attacking Jessie (had a crush on her) in 2nd grade, and not only ruined clothes (ran a marker up the seam on the seat of her pants while she was at the water fountain was the last straw) but had hit her several times the week before, I got the police involved. Each time I tried the teacher, the principal and the parents, but could get no response that protected my child. So I went to the police as a last resort. The pants taht were ruined were not cheap, but I told Gma not to buy them (why would you give a 2nd grader white pants in the first place? esp when the child was NOT a neatnick!) so that wasn't the issue. The problem was that he put circles around where he thought her privates were, and that is sexual assault here and is a BIG deal. We had enough going on at home with Wiz' violence, and were hip deep in help for him and for the other two. I did NOT want someone else's kid bringing in more problems. As it was, Jess had to take a water bottle to school because she almost passed out from dehydration because she was terrified to use the water fountain. I was beyond irate, esp after three calls to the family got NO results. I finally called the father's work - another parent knew he worked for a certain company. I insisted to the person at the company that he either called me or else I was calling the cops and he had that evening to get in touch with me. Dad waited three days, and then was angry because I called hte police. School was too, but what was I supposed to do? THe kid had been after her for months and nothing school did made a difference (and he got detention, no recess, no gym because he would go after her, all sorts of things were tried but nothing worked because mom thought it was "cute" and gave him more ideas.
the cops did NOT think that drawing on my daughter's pants while she was wearing them was "cute". The mom had told the teacher that he liked her, no harm was done, and I needed to not be "so uptight". She told that to the cops too. They told her that her son was looking at a placement for sexual offenders because it was sexual assault and it had harmed my daughter and if she wasn't real careful ALL of her kids would be removed because they learned that all five of them did things like this to other kids.
the parents very much CAN call the police. They may have to be insistent, as many cops look at things with kids as stuff school should handle. But if school can't/won't, they have EVERY right to insist on pressing charges. Frankly, if I were you I would advise a few parents to do this.
I didn't go to police right away. I probably should have done it sooner, but I gave school a chance to handle it. Parents wouldn't cooperate and support the school, so the kids didn't change. So I did what I had to and protected my kids. I hated it, and I knew the other kids needed help and not punishment, but with-o the police/court forcing things they would not have gotten help.
Learned last week that the boy who hurt Jess ended up living iwth his father about six mos later, as dad left mom and took the kids because she was telling them to do this type of thing. Now he is a teen, works at a local store and is the nicest, most polite young man you could meet.