They really do need attention, attention, attention, especially when so young. I know the only reason I was able to get Paco (who just turned a year) to be generally trustworthy in the house was because I worked at home and was able to train him and use "leave it" when necessary.
He's still not totally trustworthy. I was working on the computer today, and apparently not paying enough attention to him, so he went and started ripping at the couch cushions. His puzzle ball is a great distractor, as well as chew bones, and I've taught him how to fetch so that I can at least try to sit and work while just throwing a ball for him to bring back, but really, if I could give him belly rubs all day in between long walks every hour, on the hour, that would be his dream world, I'm sure.
It sounds like your son could be a huge help in keeping your b occupied when you can't do it, since he isn't as scared of him. See how interested he is in the obedience classes and if training the pup can be a "project" of sorts for him.