I have an 8 year old GSD named Keeli. I've been training her new tricks, when she was a pup we taught her the basics like sit, lay down, stay, come. But now that she is older I feel that she might be bored, I know that GSD's love to work and learn. So far I've taught her to spin in a circle and to cross in and out of my legs. I was running out of ideas of what to teach her, any ideas? I'd like a trick that wouldn't put too much pressure on her joints or cause her any pain. Thanks!