How would you convince her?

my fone is broken and exactly the same thing happened to LOADS of people i know hoo have my fone. I really want a new 1. my mom says no and only if i concentrate hard on playing the flute (!!!!!! boring and its over the summer!). I would like to convince him to let me get 1. im certainly not spoilt and understand some of the reasons why i cant, i just want one SO badly.