who will win?

Today was week 4 with Maizey in obedience school...my arms, legs and torso still ache every time we leave. She does a pretty great job at listening, staying, waiting, laying down, and sitting when we are at home and on walks. Get her into that ugly recreation room with 20 other dogs and she thinks she is queen of the room. Don't get me wrong, she actually is a better dog than most in the room but her constant biting at the leash tests my patience like no other. It will be the ultimate battle the last few weeks of class...someone has to win and if I let a 40lb 6month old puppy dominate 3161 Buckingham, we will have issues......