That's great that he's making progress. It's going to take more than a couple of weeks for the problem to go away though, so don't get overyly excited yet. Keep working with him, he needs to know you mean business, don't let him get away with anything or he'll start testing his boundries and you'll have a worse problem than before. Let him know he's doing a good job. Hopefully he'll see that he's getting more praise with his good behavior instead of being punished all the time for being bad and he'll start changing his whole attitude to get praise all the time. Keep updating us on his progress.