YES to all of the above. My first couple shadowing experiences were pretty lame, sometimes because I wasn't really allowed to do anything and was talked down to a lot (this was when I was in high school) and sometimes because I wasn't very interested in the particular specialty (canine theriogenology).
When I found my current clinic, everything changed. I'm rarely, if ever bored there. When I'm working small animal, I just started stepping in wherever I could. I made friends with the techs so they started asking me to restrain for blood draws and injections, I help them with surgery prep and recovery, and they will fill me in on anything interesting going on. Also, the vet has a great sense of humor and a lot of opinions, so he is fun to joke with and interesting to converse with during surgeries. I rarely get bored during routine appointments, probably because it's a very Herriot-esque rural practice so every person and animal who comes in is a character. But I'm constantly fascinated with this vet's savvy with clients and animals and I never tire of watching and learning from him. He makes a point of introducing me to his clients and telling them I'll be going to vet school, which makes me feel important and more a part of the appointment. Also, if we're between appointments, we usually go sit in the break room where he's got stacks and stacks of back issues of JAVMA (current ones too!) as well as all his old vet school texts and references. So I'll scan over the latest research, or look up a disease that we saw that day.
If I'm with the clinic's large animal vet, there's never a dull moment. He's boisterous and hilarious and has tons of impossibly crazy stories from his vet school days. He usually keeps me busy restraining farm critters, drawing up vaccines, cleaning and preparing equipment for surgeries, and will let me do injections on anesthitized animals (like penicillin and tetanus injections for animals who just had surgery). The long rides in the truck are usually really conversational, but sometimes even though it might feel uncomfortable, YOU have to be the one to break the ice and get the ball rolling.
So finding the right clinic is definitely a big part. But also try to break the ice yourself. Everyone else has given really good advice on asking questions. If you see an in for something humorous, crack a joke (a safe one that has no possibility of offending anyone, until you know their sense of humor!). Make sure that no matter what, you ACT interested. Be curious about everything and don't just assume. For example, at my clinic the vet uses PDS suture for some things and cat gut for other things. I started a long conversation over a cat spay once just by asking why he used the two different kinds and what the difference was.
There's SO much opportunity to learn when you're shadowing, and if you're already in and shadowing at a clinic, that's half the battle! Think of how many people are even having trouble just finding a place to shadow. So make the most of it. Start interjecting questions at appropriate moments and see if it sparks conversation. The more you talk to the vet, the more comfortable you'll be. Most of the time, they LOVE answering your questions. You'll know if you're getting on their nerves so you can guage when to back off a bit, but if they get irritated with even just a couple of questions, it might be time to find a new clinic. Nothing beats knowing a veterinarian with whom you have a great raport.
