We had a long talk about lying and just four days later he lied about doing an optional poster for DARE in school. When I asked to see it, he said it fell off the wall and he couldn't find it. When I told him I would ask the teacher about it he said he was just joking with me and cried and stomped about how I never believe him. He has no reason to lie and when I ask him why he does it, he says he doesn't know. What can I do?
Try focusing on the positive with your son by rewarding him with your attention when you know he is telling the truth and withholding attention when he lies. Follow up every time you are not absolutely sure that your son is telling the truth, checking with his teacher or whoever might know whether or not he is lying.
It's difficult to change dishonest behavior without professional help, however. Start with the school counselor. He or she may be able to give your son some individual time or include him in a small group on honesty. The school counselor or your pediatrician can also refer you to a therapist in your community for additional help.