Try the reusable/washable ones.
I had the same problem with Poptart. He loved chewing up his pads, it was his favorite thing to do. I even tried a pad holder. It didn't work at all, he still found a way to grab it and chew it up into pieces. I got so tired of having to pick up pieces of shredded used puppy pads. So I took someone's advice and bought the reusable ones. What a difference!!! The pads are thicker made with a cloth material so they can't chew it up. They even absorb twice as much as the disposable ones. Plus they save you money since you can wash them and use them over rather than throwing pads away and keep buying new ones. They wash up so nice, they are like new everytime they are washed which is amazing if you knew how much my boys peed on them. I was sure they would stain with my boys but nope I washed them and couldn't believe they came out looking new, not a single stain, they looked perfect. It is the best money I ever spent!!
Poor Poptart didn't know what to do with himself, he realized he couldn't tear these pads up. The problem was solved.
I got mine at
www.valethics.com
and I would recommend them to anyone!!