N.C.
My son also does this, with a lot of enthusiasm. One day, he tore one of my favorite books from my own childhood, and I had had enough. So, I told him that tearing things is not acceptable, and that when you break something you have to fix it (in my current kindergarten where I teach, we have this unofficial rule of "you break it, you make it" - meaning, if you knock down a friend's block tower/break a toy/kick the sandcastle someone built, you help them make it again). I got some scotch tape and my son and I taped up the book, and he has not done it again. I'm sure he'll find other things to break in future, but the same rules will apply then, and we will work on fixing the broken items together. Taking care of things can be taught, even to very lively (and well-meaning) kids.