oooh puppy classes are fun and even if they "fail" it is good socialization and playtime for them
when i had a german shepherd, i took him to class (like a previous poster said, it was more for me than him as i knew he would outweigh me at adult weight) ... he was the youngest puppy there and had "accidents" three weeks in a row (pee and poop!) ... he still passed!
i think the trainer just felt bad for us because she saw how hard we were trying lol