These dogs are very intelligent and have to have a JOB. Is it possible for you to enroll her in some agility training classes? The problem is that she's probably getting bored out of her gourd. She probably needs more than 15 mins a day of exercise. She needs something to stimulate her brain. I know, I have one myself. Destroys the place if she doesn't get hours of exercise and stimulation daily.

Contact a reputable rescuer in your area and find out if they can refer you to a good trainer. Also look into agility classes is my suggestion.

Kelly