I suggest dominance training, and looooooong walks. Look it up more on the web, you can read a lot about it.
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You should get your dog neutered, as that is the responsible thing for a pet owner to do-however there is no guarantee neutering him will make him "calm". Since the dog is your responsibility, take care of it. If you don’t like how your mother handles dogs-when you are old enough I suggest you move out and get your own place. This way you won’t have to worry about her mistreating the dog, re-homing it without your permission, and anything else you may be worried about.

Edit: You were asking for people’s opinions on the matter, correct? For solutions? That is what I gave. It’s already done-so you will have to live with it until you can move out. That is the only thing that can be done. You should have thought about your mother’s past with dogs before getting a dog. Obviously you did not ask about neutering but you mentioned it in your original question, I was stating that neutering a dog is no guarantee to calm a dog down, but is something that should be done by a pet owner. Getting a dog as a gift is bad thing, while it was a gift for your graduation if you wanted a dog you should have gotten it when you had money to pay for it yourself.

I apologize if my opinion and response to your question offended you-I was giving my honest response to you for the situation as I saw it from what you provided. Your mother already has an idea as to what dogs are, that they are something that can be disposed of when it no longer suits her needs. Some people are like this, and dogs shouldn’t be brought into a household with a person like that in the household, because chances are they will never change their view on dogs.

Edit again: I gave you a solution: Move out-there a high chance that even if you talk to your mother, she won’t change. If you want to live a happy life with your dog, moving out in the only solution.

As for How to talk to your mother about her opinion on dogs- Sit down with her and talk. Tell her you do not like how she treats dogs, that they are a lifetime commitment and once you get a dog you should provide it with a forever home for it’s whole life. Take her to a shelter and so she can see how the dogs there are suffering because people thought they can dispose of them when they no longer suit their needs.
Show her how many dogs are suffering because people don’t think to do research on breeds before adding them to their household. Do research, provide facts. Show her the reality of dogs bought from pet stores that are abandoned because they have temperament issues.

That’s what you need to talk to her about, I apologize I did not say this in my original post but I’ve seen so many people that get dogs as gifts and then can’t take care of them or get them and then cannot provide them a forever home that I’m not exactly nice when addressing the issue of getting dogs as "gifts" that I got sidetracked from the original post. My apologies again if I offended you with anything I have stated.
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