My pups were doing the same thing. I looked it up on the internet and one answer I got was that at that young of age, they are discovering things. They call it mouthing. Their mouth is the way they can test what things are as far as flavor etc. Mine were chewing on cotton batting out of my couch, wood on the chairs etc. Anything dropped on the floor is a new discovery for them. Their answer was to stop it is , to catch them, tell them no its bad ,and give them something to replace it that is allowed to be chewed on. They are teething too, so I made water Popsicles. They love to chew on them. They are cold and feels good on their gums.