What to do about own son's aggressive behaviour

[Bananas]

Hello everyone - I am a first time poster and would appreciate some advice. I have been running my home daycare for just over a year now and really love it. The only problem I have is my 3.5 year old son. He is a sweet and sensitive boy but also loves rough "boy" type of play like wrestling and play fighting which I discourage as much as possible. The real problem is that he is mean to all the daycare kids. He takes away their toys, tells them they can't play and to go away and sometimes get physical with pushing and hitting - in the latest incident he bit a 4-year-old little boy (his best friend) and left a bruise of a bite mark of the boy's leg. This little boy complains to his parents about my son a lot and also told them that it was my son who bit him. Naturally the parents are concerned about this behaviour.
I am at a loss as to how to get my son to be nicer to the other children... I have tried to be extra loving and patient with him and I have tried time-outs. I have tried talking to him - nothing seems to work. I am not only worried about the other children in my care but also that my son may be deeply frustrated with having to share his house, toys and mommy with all these kids.
What can I do to make him kinder and less violent but also to feel a little happier about having other children here?

[JennJubie]

There is a great website: http://www.freeprintablebeh aviorcharts.com

If you search "caught you coupons" you can find a printable coupon that reads "I kept my hands to myself". I use these with my own son, (who has behaviour issues), and when he earns a certain amount he recieves a reward.

[gcj]

I think the most important thing is that he feels that he has is own toys and his own place. His personal toys stay in his bedroom and the "daycare" toys and in the daycare. There needs to be a distinct difference. What's in the daycare isn't his. Also, at 3 1/2 he can certainly go play alone in his room to just get away from it all. He doesn't always have to follow and be in the "daycare environment" all the time. It's tricky, but there are double standards when we have our own kids in our daycare.
Punish bad behaviour (keep doing time-outs) and I like the coupon idea of caught being good. Just make him feel special.
I hope things calm down. My son was always a challenge in my daycare and now after 5 years of doing daycare, it is MY daycare for the first time, since both my kids are now in school! :D Hang in there and good luck!

[Bananas]

Awesome - I have heard of these behaviour coupons and will definitely try them! Thanks for the advice!