The "watch" command is invaluable but once the dog has an idea of what you expect, you need to increase the stimulation he receives in order to get the reward. First the dog should have at a minimum 30 seconds and preferrably 1 minute watch without distractions. It needs to be 100% consistent. Once this is established (don't move onto distractions unless it is) then you move onto distractions. Minor distractions at first. Perhaps someone walking by or making a loud noise. I even move parts of my body but give a UT-OHHHH sound if the dog looks away. Then I break out and start over. Distractions in the house must be 100% before moving them outside. Remember to up the stimulation as he learns and progresses. Perhaps a favorite ball bounced in front of him or someone saying his favorite word. Don't rush moving outside before he is ready. This is a very gradual process. When you do go outside, you need to up the reward to something even more appealing than you used in the house and more appealing than the distraction. Verbal praise as a reward needs to be exstatic! I tell people if you aren't making a fool of yourself when you praise your dog (especially in private) then you are not giving enough verbal reinforcement and praise.

You are on the right path with doing formal obedience but working at home, one on one, is the best practice. Remember, when you start, your number one goal is to set the dog up for success. In order to do this you need to start small and work your way up too big. I'm sure you can do it since you have accomplished so much already with Jack! Happy Training!