I really want a new phone...?

My phone was revoked a couple of months ago for reasons that will be left unsaid. My birthday is coming up in September and I would really love to get a new phone ( I have been good lol ). The device I would like to get is the new Samsung Gravity T ( aka, Samsung Gravity Smart ). I know I won't get the phone without work, therefore I was wondering what sort of agreements my mother, her boyfriend, and I could come to. Do you have any ideas? I have ok grades and am I'm working on my attitude problem. I'm also a heavy text-er, so is this an appropriate phone for me? Oh, and I'm 13.