over excitement

Question
My mixed breed spayed female lab mix 6 month old puppy Rosy is highly excitable. We are in puppy classes and she has supervised play times with dogs through these classes.  Everything makes her crazy: people, dogs, birds, squirrels, toys, walks.  Then she gets tired and snappy.  I have stopped playing "tug", she is often in her x-pen or tethered to a door knob by her big comfy bed but just can't seem to settle.  I try massaging her, ignoring her, only petting her when she's calm.  I do work very had with her and she's a good learner.  Will she outgrow this hyperness?

Answer
Maybe, maybe not.  But, you can do a lot to reduce the excitability.  Try clicker training her to be calm.  Petting is nice, but she may not be "getting" that that is her reward for being calm, and you may accidentally be reinforcing anxiety.  There's a nice article by Pat Miller here that might be helpful to you:
http://www.accessmylibrary.com/coms2/summary_0286-34519418_ITM
Try some interactive toys to give your puppy a "job".  Isolating her by tethering or confining her will only make things worse - instead, actively train the dog, and only pen her when you can't be there to supervise, or when she really needs a nap or a time out.  If she's a good learner, then clicker training will be a snap.  Also try the free lessons at www.clickerlessons.com.  This is all mental exercise, which tires dogs out, too.  Consider doggy day care, unless she is overstimulated by too much play.  Or, set up play groups with friends and their puppies (maybe someone from class lives near you).