K.D.
First of all I agree with the moms who say alone time with you would be a good thing for him so that is one idea. I know this sounds a little crazy but try rewarding him for the good things he does. As a sort of positive reinforcment. Get something and mark it with stickers and tell him for every few stickers he will get something special. Even if it is something little like a sucker or some kind of small toy. Maybe negative enforcment just doenst work for him. Not saying what you are doing is wrong. I have worked in daycares with lots of diffrent kids and had to come up with diffrent ways to make kids lisitin. I have also taken a developmental class where we talked about diffrent ways to enforce good behavior. Just an idea though. Feel free if you have any questions to get back with me.