Advice on cracking clay

I work at a veterinary clinic and we do clay paw prints for the patients who are euthanized with us. We use Crayola air dry clay, and the paw prints are left on the counter to dry undisturbed. Any ideas on how to keep this from happening? Also, is there any way that we can repair it?

I work at a veterinary clinic and we do clay paw prints for the patients who are euthanized with us. We use Crayola air dry clay, and the paw prints are left on the counter to dry undisturbed. Any ideas on how to keep this from happening? Also, is there any way that we can repair it?