There are many ways to stop this activity. One that I learned from dog obedience school was to put a few pennies in an empty soda can and tape up the hole. If the puppy is doing an unwanted chewing behavior shaking the can makes an unpleasant sound, usually enough to distract them. However if you throw the can and it hits the floor near the unwanted activity, it's enough to scare the puppy and make him/her think twice before chewing on that chair leg. Make sure that the puppy is unaware that you are the one throwing the can and don't hit the puppy with it either. When you are not home... using a kennel (crate) is best. Kennels keep both your puppy and your home safe when your not at home.