Oh boy! Where to start.....
What have you tried so far?
Does he get plenty of exercise each day....enough to say he's worked hard for long enough...that he's really burned off that boundless energy he must have?
Is he left for long periods at home alone while people work?
I am sorry to say that I find this hysterically funny. Rat Terriers are famous for their boundless energy and enthusiasm for chewing things up, especially when they are young like yours. I suggest kennel-training. Buy a kennel big enough for a bed, food and water, plus enough room to play with a half a dozen toys you will add. The toys should be various types: a rubber ball (big enough not to get caught in his mouth), a large rawhide, a stuffed animal he can chew up, a rope-toy, and maybe an old sneaker with laces and eyelets removed. Get 2 small stainless steel buckets (NOT made of anything else!) with handles, and 2 metal hooks, so you can fasten them to the inside of his kennel (he cant chew them or spill them) for food and water. This is his 'safe house' since he will not be reprimanded for anything he does while he is in there. He will only be closed in when you cannot watch him, and it will be left open for him when you are home. Also, give him LOTS of playtime and excersize! At least 2-3 times a day, he needs an hour or more to be allowed to run and play. This has worked wonders with my terriers. By now, I can say 'kennel', and they will go in, and even stay there with the door open until i ask them to come out! Hope this is helpful!
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