I'm going to go ahead and say you should really get a trainer. Someone who has experience with GSD. I have been having the same issues. My pup also is perfectly wonderful with my kids but turns into a jumping, lunging and barking beast out and about. We will be doing private lessons with Zoe. I've read 100 posts on here and it really seems like the kind of issue that can't be helped over the Internet. Or at least that's what I've learned.
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