Alpha, I think I would terminate too! That is unacceptable from a child that age! He is not a little 18 month old who is testing the waters. At almost 3, a child should not be hitting and certainly not biting! My children NEVER use this kind of aggression with me or with each other (my daughter went through a short biting phase at around 12-14 months, but that's it). My tolerance for violence is low. I will work on it with a toddler (by toddler I mean 18 months to 2 years) if parents are supporting me. At the first sign of hitting or other acts of aggresstion, I start talking with parents about how to nip it in the bud. If a child that age hit me in the face with a toy on purpose, I don't know that I could continue to work with that child.