Is Parker a Corgi mix? His lil face reminds me of a Corgi.
I had phenominal problems at around 1 year old with Fozzie, trying to get his attention around other dogs/smells/people. He would be sniffing around in the grass while I tried everything! I switched from soft rolled food to a mixture of dried cheese, dried/overcooked hot dogs and bits of cheetos... and I started clicker training. Different dogs need different motivation. He is incredibly attentive when I'm using the clicker because it is a GUARANTEE of a reward, and it lets him know instantaneously when he's doing something right. It also helped me to be more consistent, learn to shape behaviors rather than lure or force them, and train him to watch me. I use the clicker with him to teach any new commands and to practice with a high level of distraction, and it makes all the difference for him. Make sure you use super duper high value treats with the clicker, especially to start off. Fozzie loves cheese and cheetos (I know they aren't healthy! but he eats really healthy otherwise, honest...) but Parker might not. One treat that I've noticed every dog is obsessed with is chicken hearts (and/or gizzards, liver, lungs, etc) sprinkled generously with garlic powder and baked until they're dried out. Dogs go apeshit!
I work at Petsmart, and I don't even recommend the classes... the environment alone, IMHO, is not condusive to beginning classes. A small room, too many dogs, a store full of distractions. Also, the training that the trainers go through is very minimal. You might find a great trainer at Petsmart, but I don't know of any personally. D; I recommend finding your local Obedience club, and/or behaviorists in your area that offer classes. Positive reinforcement only. Attend a class just to watch before you enroll. The vast majority of the training that you do will be at home, at parks, etc, on your own! Educate yourself! There are lots of amazing training books out there... I highly recommend Don't Shoot The Dog by Karen Pryor, Control Unleashed by Leslie McDevitt and Click To Calm by Emma Parsons.