I'm looking for some advice on how to keep my 8 month old GSD occupied. I can only take her for so many walks and practice her sitting, laying, and staying so much. She loves to chase the tennis ball and is extremely smart and a quick learner. Still I can't make her happy. We can be outside practicing training and walking for hours and she still isn't satisfied. I was wondering if anyone could give me some advice for me to set her up with something to get her engaged for a while and still have some sort of learning aspect to it as opposed to giving her a kong or something like that.