I currently have my 5 month old in puppy class. I was going to go through all 4 classes at Petsmart, but now I’m thinking I could save about $300.00 and teach my dog the same things (and probably more), if I invest in a good book or DVD. Any suggestions? I’d prefer a DVD, but books are fine too. That way I can also apply the training to our other two dogs at the same time.