Does Sparky have the run of the house? If so, you could consider getting a baby gate, choose a place in the house, could be the bathroom (where he can't get into much trouble), and put him there for say, an hour, then let him out to play for half hour then put him back in. It trains him for alone time and to potty too.
Leave some chew toys for him in there so that he knows that he's supposed to only chew those toys and not anything else.
The puppy class that I go to suggests that if my puppy has done something wrong, like if you catch him in the act of chewing your table (for eg.), you say something like "uh-oh" and send him to his crate/baby gate space for a time out, say, 15 seconds and then let him out. The next time he does something naughty, you keep him for say 30 seconds and you increase the time every time he does something naughty. The important thing is that you catch him as he's doing something naughty and not after.
After a while he should get that what he was doing is not right and he will be given a time out for that and puppies hate it coz they would rather play with you. It's not much fun being alone, is it?
