my new dog

Question
Hi,
I just got a 1 year old boxer lab mix from a humane society. He is so friendly and playful. He knows sit, laydown, and his new name just in 4 days. We are working on traning him and making him know who the leader is. My fiance is having a better time then i am, i am finding it really hard to have him heel when we are on a walk because he pulls me and we live in an apartment on the 3rd floor so for some reason when he goes up the 1st set of stairs he pulls me down the hall and doesant want to go up the other set..what could i do about that? He is so good with adults and even some kids but for some reason other chilren he growls at and backs off i dont know what to do. He does it to random ones that are outside of our building when i walk him or he barks at them. I am not sure if he is scared of them or what but my fiance and i want to nip this in the butt as soon as possible because i have nieces and nephews and we want to start a family in about a year or two. Other then that hes a great dog/breed. Any info you could give me would be great!

thanks!

Answer
I think the best way to correct these issues is to take him to obedience classes,as it will socialize him and also tighten the bond issue that you have. So what would be best would be for you to take him,and go through the class with him. a lot of times barking is a sign that a dog isn't used to a situation and taking him to classes will get him exposed to these things