It is normal behavior for budgies to want to chew and tear up something. Sometimes they take it out on a perch, sometimes it’s the paper on the bottom of the cage. They need something to chew on. It is a natural behavior and it helps to keep their beak in shape. A great idea is to provide them with a better outlet for their chewing. Bird KabobI recommend getting a soft wood toy made for birds to chew on. Many pet stores sell a toy called a Bird Kabob that is made of soft wood that is perfect for budgies to chew up. See the photo on the right of the Bird Kabob that still has two of the pieces of the soft wood on it. You can take the individual pieces off and attach them in the cage where the budgies like to hang out. The chewed wood can get messy so I recommend using a cage skirt if you attach it directly to the side of the cage. There are also other toys made for chewing, just remember that budgies need a softer material, so toys made of popsicle sticks would be good, but ones made of manzanita sticks would not. Pet birds should always have a toy or item in the cage that is meant to be destroyed, so keep in mind that such a toy would need to be replaced every once in a while.