I was going to suggest a doggie daycare, or dog park, but I see that has already been done. We have a daycare we love, where many of the workers also teach or help with classes, so they reinforce all the basic commands. The dogs are either inside, or in one of 3 outdoor fenced in areas (including an agility yard) and there is never more the 10-12 dogs per staff member. The dogs are only kenneled during 2 nap times periods, so when I take them from 7am-4pm, they only spend 1 1-1/2 hrs in a crate...the rest of the time they are playing, and boy are they tired when they get home!!

If these option aren't available to your sister, she many try to find a "sport" her dog likes...flyball, agility, freestyle, etc.

Sadie is a super hugh energy dog with not much of an attention span. She loves to do tricks though, and we have used this to "control" her...for example, when we took agility there were times we had to stand inline to use the equipment. Sadie would pull all over the place. By gettingher to do tricks, like spins, rolling over, etc, while in line, she was much more focused. It is amazing how something as easy (and fun) as teaching new behaviors can help calm and focus a dog.