We have the same problem with 3 month old Dakota. He's either an angel or a terror. He can wind himself into a playing frenzy without too much help from us. He's better about the biting (I haven't had bleeding forarms for a couple of days!) but if I'm sitting on the floor during one of his frenzies, he will run, jump and lunge at me with his front paws. What works somewhat for me is a game we call hall ball. We have a long hallway and I will throw the ball over and over in an attempt to have Dakota run his energy off, but sometimes the energy seems never ending. Do any of you watch the Dog Wisperer? Cesar Millan claims the very best thing you can do is a 45 minute power walk in the morning and again in the evening. I'll start that as soon as it starts getting lighter. We're also starting pupping training on Feb 21.