Stay consistent! You mentioned you just don't feel like he hears you, well, speak directly to him. Away from his friends. Give his straight commands, "I told you not to throw the toy. What did I say?" Make him repeat it back to you. "Did you throw the toy?, when you do things that I tell you not to do, that is wrong. Is it wrong? And when you do wrong things, it makes me feel bad, and because I want you to do what's right you have to go sit in timeout for throwing the toy. Why are you sitting in timeout?" Make him talk to you. After timeout ask, "Why were you in timeout? Are you going to throw the toys? What will happen if you throw the toys?" and repeat and repeat everytime he acts out. If it's that he's not being kind and telling others to leave him alone, talk to him. He is old enough to learn consequences and you need to try your best to stick with them. If he's being a copycat explain to him that his friends will not like that and like I said, make it speak it back to you, and he won't have friends, and you are not going to make the other kids be friends with him if he's not friendly.

Good luck.

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