[Quadraphinic]

I agree, this is also the time when the puppies get their bad habits. Training to sit, sit stay, down, take it, leave it, drop it, come when called, and gotcha are all good ways to tire them out. I do this with Gina several times a day, she starts to get destructive if we don't work her. Gina is almost 19 weeks old now, so I know what you are going through. Good luck.
Cheers Quad