You know, that thing that dogs do when they tear around the house bouncing off the sofas/walls. Because Jasper does this once every other day, and while the running like a loon thing can be funny, the jumping up and chewing the DC isn't. At the moment, I am grabbing his collar, making a sort of 'Nnnggghhhhhh!' noise at him and putting him out in the garden until he calms down. But I really need to stop the jumping up and snapping/chewing at the children, because they are beginning to get frightened of him. Any tips?