Something else you can do if you have the Kong toys ... a lot of people put food in them and freeze them. The dogs love it when the weather is hot and it keeps them busy for hours! Good with peanut butter in them too. Or you can mix some of their regular dry food in with unflavored yogurt, put it in a Kong, and freeze it. They love it and the yogurt helps with the natural "gassiness" of some breeds ... like Bostons!
I used to get the rawhide chews for mine until Ragan came very close to choking on one. She would chew them until they were a gummy, sticky, floppy mess and then she tried to swallow one long strip of rawhide whole. It was long enough that one end was all the way down in her stomach and the other end was just visible in the back of her throat. It was completely blocking off her airway, she couldn't even make a noise, and if I hadn't noticed her when I did, she would have died. Never again! And never any more of those "Greenie" things either. They can splinter when they chew on them and injure them.
The Kong chewy toys are the best I've found. They're almost indestructible. Mine have a big black Kong bone they've chewed on for at least four years and there aren't even any teeth marks on it yet! With the Kong toys, the color makes a difference. The black ones are the strongest, made for big dogs or enthusiastic chewers. The red ones aren't quite as sturdy and are made for smaller dogs. The blue ones are softer and made for puppies to chew on.