I would recommend playing fetch with him and giving him a good run about the house. He needs the exercise. Then you could give him something to chew on to occupy him. He's a terrier and is high-energy. A tired yorkie will be a good yorkie.
Also, mine used to love to chew on bully sticks when she was teething. What a blessing those things were! I swear she would have eaten the whole house if not for them.