Training issue or just a puppy?

We have a 7 month old Spitz x Border Collie, who for the most part has been great with training! We've had her since 8 weeks. BUT we are having major issues with her jumping up at strangers and just generally being ridiculously excited around people. She isn't allowed to jump up at home, and we've tried just sitting quietly people watching since she was able to go on walks – no change, just manic love for people. We also enrolled her in a highly recommended group training school, but she just went nuts the whole time and the trainer just kept telling us off for not keeping her attention better 🙁 we actually didn't finish the classes because we felt like us and our pup were being looked down at from how excited she was. My question is – is this par for the course with her age/breed, or are we doing something wrong or missing something with her training? We love taking her out but it's so stressful going anywhere with people! If you have a high energy breed, what worked for you???