What has helped us with training and is doggy daycare. We take ours 1-2 times a week. It keeps them active and helps with socialization with people and other dogs. They are much more calm and easier to work with. Exercise is good for heath and mind.
Edit:
We take them to Camp Bow Wow in West Seneca. Super nice people. They have camera’s so you can watch the pups while they are there.
www.campbowwowusa.com
My dog has chilled out a lot. I keep him at my moms house ( she is 1.5 miles from me ) she has a boxer also, so they run around and be retards all day. They have free range of 2 acres and come in and out of the house as they please. He is still clumsy, he will turn and bump something not realizing he knocked a child on his butt, then turns around and licks the kids face off.
I rescued a dog who spent his first two years of life life in an outdoor shelter and was super aggressive towards males when I first got him. He knew the sit/stay a bit so I decided to work on his aggression and checked out the dog agility class run by a super nice lady Jennine over at the Canine Sports Complex loacted here: http://www.positivepet.com/ a year later my pup is allowing other males to walk him and kneel down to pet him with out being aggressive and dominant plus hes learned a bunch of new tricks in a positive environment with other dogs. Besides agility they also have trainers that do puppy training class, foster moms n dads class, dock jumping, and any level of training class as well. Its not expensive really. I go Saturday mornings and for an eight week session its 110. But the price drops after each session. i think i started off paying 150? for the first eight weeks. Seriously call them n see what they can offer! Good luck!
edit: if you arent crate training the dog, leave the TV on and put it on a channel like DIY or some home channel so it can get them used tro doorbell sounds and other random people sounds like talking/yelling/construction/thunder. also if hes cooped up for a long period of the day you NEED to take him out for a long walk or play with him to release energy. Aggression in dogs can stem from being bored all day and not releasing energy as they would in the wild. Yes dogs get bored!
We recently used K9 Connection for our Great Dane puppy. He wasn’t overly bad, but had some bad behaviors that needed help. Josh, the trainer at K9, is nothing short of amazing. The difference with our dog is night and day, not only with the problem behaviors, but just manners in general. I highly recommend them.