2 yr old w/aggressive behavior

I have been guardian of my nephew for 8 months now.  He was placed in foster care since he was 4 months old and we are now the 4th home that he has lived in.  He has been going to daycare for 6 months.  His behavior is getting worse.  He is hitting, biting, pulling children down.  His teachers have been putting him on time out and now he doesn't even stay.  He gets out of his high chair.  He gets put on time out everyday and today I was just notified by his teachers that he bit a child in his face because he wanted his cookie.  I thought that he was adjusting well until now.  I thought that since we got him at 18months old that he was young enough where he didn't get affected, but apparently it seems that he may be.  His teachers want me to do something about him.  I explained that we use time out here and that we don't teach him aggressive behavior.  I also have two other children in our house 10 and 5.  They have never been a discipline problem and they do not show any aggressive behavior.  In fact, Tyler does not treat my youngest son very nicely.  I have contacted a behavior health facility to set up an appointment.  What can I do in the meantime.  His teachers feel that I should be punishing him at home for what he does in daycare.  I feel that it is difficult for Tyler to understand at his age by punishing him for something he did earlier in the day. I think Tyler learned alot of his behavioral problems at the daycare, but I do think that he should be responding to time out and he's not. Please Help!  I need your advice.  Also the teachers would like me to give them some advice.  How can I make him treat other children nicely when I'm not with him during the day?  Any and all advice welcome.  Thanks.  Cathy

[Kevin Kennedy, Ph.D.]

For older children it does make sense to discipline them at home (in addition to whatever happens at school) for misbehavior that occurs at the school. However, this does not make sense for a child of two. Continue to set sensible limits at home, particularly with regard to (a) prohibiting aggressive behavior and (b) insisting on adherence to parental instructions. Time out is far and away the most effective method of discipline for children. Be sure the time out occurs in an adult-size chair, and employ a cooking timer to track the time out. If a young child does not remain in the time out space, it is sensible to hold the child in the chair - i.e., refusing to cooperate should not be an option.