Respect and Respect

I got a call from Isaac's teacher yesterday. She needed to let me know that Isaac has been talking back to her and her assistant for about a week. He has told them that he did his work when he had not, and he told the aide that he already did his math the right way so he was not going to do it again.
He's been pretty ornery at home lately as well. He's been picking fights with the other kids and crying hysterically every other minute. He keeps telling me that they are being mean to him, but they really arent. I cant figure out where his mood is coming from. He seems to be getting enough sleep, but no excercise.
I take responsibility for his lack of respect at school. I am sure he has heard me complain about policy and authority. There are certain people at the school that I have no respect for. BUT I always treat them, and everyone else politely. The two concepts are mutually exclusive in my mind.
So, we had a family rap session about respecting adults. I hope it helps.
*Update: Both boys were diagnoised with Strep. After 72 hrs of antibiotics, Isaac has really lightened up. He's been telling me every night that he did not get in trouble at school so I think he was just not feeling well.