bunjee and i are in the petsmart puppy class right now and using clicker training. i think the techniques and it's been really helpful. my only concern so far is that bunjee is so distracted during class, he doesn't like to pay attention.
at the first class, bunjee was 10weeks, 3 lbs or so, he was the youngest and the smallest of all the pups, so needless to say he's a bit aprehensive about socializing with the other dogs. he got a little better during the second week and started coming out from behind my legs when the other dogs wanted to sniff him.
my class has a min pin, a pom, a jack russell, a cocker spaniel, and 2 labs. so their sizes vary. the trainer also suggested that i stay after class and socialize with the pups in the next class as well, to help bunjee outta his shell.
so overall i'm pretty happy with the class. of course, your mileage may vary depending on the class and trainer, but for the price, it's pretty good!