OHHHHH chewing is sometimes a HUGE problem here!
I would not feed a dog Science Diet. btw
Old cotton socks are great. You can take long tube socks and tie a knot. You can even stuff something in it like a banana or peanut butter. They will chew on it for hours. We also use pressed rawhide bones. The pressed last longer. If you can get real bones these are great just be care they are hard and raw bones are best. But honestly the best for a chewy crazy dog is a squeaky ball inside of a tube sock with peanut butter on it or I buy Wild Alaskan salmon oil and squirt it on.
This is a helpful site for dog food.
http://www.dogfoodadvisor.com/