Why does my puppy refuse to walk

Question
Hi There
I recently bought a four month old puppy from a family that lives on an acreage. Hes a Leonberger / Rotti cross and is not fixed yet. The dog was not really socialized well and had never been walked on a leash before. I try to walk him three times a day and everytime we go for a walk he will be ok for a couple of minutes and then all of a sudden he will lay down, whine and refuses to move. I have tried bribing him with treats, calling to him, giving him tons of positive reinforcement, and even tried just pulling him but to no avail. He will let me pull on his collar until he makes choking sounds but he will not walk. I have had to carry him home almost everytime and at four months old he is already over 30 lbs so its not easy. What can I do to get him to walk? Also, he had never barked before and then my neighbors kid came over and he went crazy barking and growling at her. Heres the thing, the little girl was black and hes never seen a black person before...Is this common? Thanks for taking the time to read my email and I look forward to any advice you have on training a puppy. If you have any good tips on keeping him from whining that would be appreciated as well. He starts his obedience classes in one week

Answer
It can be a little difficult sometimes with a dog that didn't have the socialization it needs when young.  If getting out in front and coaxing doesn't get a puppy moving, try dropping behind it and running by in baby steps calling ''Go, go, go!'' In a happy, excited voice.  I hope that gets him moving in time for class.  A good class will help a lot.  

It is possible with the little girl that he never saw a little girl before.  I am not sure there is an inherent problem with blacks and dogs.  Certainly many black people love dogs they have.  Many dogs do react negatively to blacks.  The next time try to remain calm yourself.  The dog will sense your stress and blame it on the girl.  Greet her warmly.  Make him sit and have her come up to him.  It would be better if she keep her mouth closed to hide her teeth and avoids looking him in the eye.  Dogs see both as threatening and and aggressive.  Work at exposing him to other children and blacks.