Well, it took all week, but our experiment finally finished up! On Sunday we ate fried chicken drumsticks for lunch and saved the bones. One bone we let dry out. The other, we put in vinegar. Vinegar dissolves calcium. As the week passed, the bone got softer and softer. Finally, on Friday, it was flexible enough to bend!
Nugget was fascinated by this, and carried the bones around the house for a while this afternoon.