Remove the cars altogether,set some bounderies and do time out when he is disruptive ,when he is at school it is up to them to deal with it.in the same manner. If he hits friends he doesnt get to be with friends.
this is new behavior i know most of it has to do with the new schedule with full day kindergarden,and yes he has been with other children his age he was in pre school last year,we do time out take away his toys(like if he throws them in a tantrum)but it dont seem to work.last week he throw a hot wheel car at his friend missed and hit my neighbors new car and i had to pay to fix it.
is this a new behavior? has he been with other children his age before? what are the consequences when he does these things?