Positive reinforcement works wonders. Tel him how much you like the things he does and be very specific.
Ignore behaviors that aren't disrespect, disgusting, or dangerous. Don't sweat the small stuff. Preschooler love attention. Use redirection-give him something else to do.
Be consistent. Time outs should be no longer than 3 min and should be administered as soon as he does something wrong. Don't yell, just say. "We don't _________. You will have to go to time out.' Be calm, don't give him the power to upset you.
Above all, be consistent and follow through. If you say you going to leave the store if he whines, leave immediately when he whines. Do this even if it inconveniences you. Don't try to bribe (if you stop, i'll buy you a toy). You have to show him that you make the decisions, you are the one in power. Best wishes.
at 7:29 AM on Oct. 23, 2008