I forgot to say that in the summer I take an empty sour cream container and fill it 1/3 of the way with water and freeze it. After it is frozen I add in some chopped carrots and another 1/3 of water. Refreeze it and add a few more chopped carrots and fill the rest with water. After it is all frozen then I run the edges under warm water and get the whole thing loose. I through it in the back yard while I am gardening/ doing yard work and it entertains him for hours and he gets treats when he licks it enough.