German Shepherd pup biting

Question
My female GS is 3.5 months old.  She has always been very mouthy and I can not get her to stop. I have done all the things advised to me, ignore, walk away, give her something else to chew, yelp, firm no and then good dog when she,lets go ,etc. Her "mouthing" is more than that, she is just plain biting and when I try all to discipline her, she gets angry , growls and comes back and bites harder at me.   I now have her in obediance training and our instructor has "FINALLY" decided to listen to me after seeing how bit up my arms and legs are and seeing her bite me in class.  She starts out as a game but gets angry at discipline.  I am at a loss with her as I know she has alot of potential but I can not have a dog around that bites for sake of not only myself but my grandchildren and all people in general?  Is she too young to try a shock collar? I need help fast.  She does treat me as the dominant when we walk, she stays at my side or behind me, she always enters or leaves the house AFTER I do, she has to sit and wait for me to give her her food dish. My only problem is the biting. What else can I do?

Answer
it really sounds like you are doing the right things.  It takes longer with some puppies than others.  The yelp is highly effective with biting, but you must be very consistent.  Each and every time she bites, you yelp and withdraw your attention.  A tougher task is getting others to do the same.  It sounds like your instructor is doing a good job.  Many classes fail to teach the owner, that they are top dog.  Such classes are useless.  For more on this, see  www.dogbreedinfo.com./topdogrules.htm

Go ahead and talk to your vet about spaying her.  As far as her behavior goes, the sooner the better.  Your vet may want to wait for physical reasons.  There is some debate on that.  In most cases, I suggest going along with your vet.