My son is 2 years 9 months old. He has a classmate of roughly the same age. The class is for kids under 3 and over 2.
That classmate bites or attempts to bite my son. My son is his only target in class for some reason. He does this when the teacher is not around. My son doesn't bite back or complain to the teacher. There are bite marks on his hand, which I have shown to the teacher. The teacher said that this behavior was common among children of that age. The only defense my son has is a weak attempt to push the other kid away from him. So far this has happened 3 times.
Since this is happening in preschool, what steps should I take?