Puppy versus adult

Not to exhaust this topic, but I just wanted to add another note about our continued experience regarding Diego being only 7 months old when we got him as a service dog. He is now 1 year and 4 months old. I realize Golden Retrievers take a while to mature. He has done fairly well, but he is still so incredibly goofy and excited. This is still very difficult when I take him to work with me. He looks forward to seeing the students and other staff and finds it near impossible to ignore them. Since he so desperately wants to socialize (which is his nature...which is why he is great for autism...) he ends up getting growled at by me because he is not supposed to be socializing while he is working. I often feel like it is a tough thing to do to a Golden Retriever puppy. Now that I understand much more about the breed, I have learned that these dogs are social by nature. They are prefect for kids with special needs because of their gentleness and non-agressive nature. While that is fabulous for a perfect pet, it seems almost cruel for a service dog job. Diego almost appears depressed as he lays under my desk at school. I may be giving him human emotions, I don't know. When he is not asleep, he is staring at the kids from under the desk. They are sad they cannot pet him and he really wants to sniff them for hours. Is this still puppy-like behavior? Will it begin to diminish as he matures? I just do not know. I do, however, feel like he would be a better service animal when he is all grown up. Right now, he is just being scolded for being a puppy. Sad...