HELP PLEASE? not stupid relationship question..?

its a good girl friend of mines birthday, her seventeenth, and i cant think of what to make or get her. not totally sure. got ideas but i dont feel the money output is appropriate :P ha. she does track with me, sings with me in our schools highest choir. she WANTS to learn guitar. i play guitar, piano, tenor sax, b etc. etc. so im still not sure what to get her thats material or at least a cool card or something