Realistic themes for a sweet 16?

okay so its my birthday in september and i am 16! :) i need good ideas for a fab party but too eccentric coz i have kind of a low budget! maybe a theme? i thought maybe disney princesses or something girly like that. i am thinking of renting a hall out and have about 30 people to invite. all ideas welcome but please stick to the point and if you dont like my ideas then pleaase dont put inpropriate comments!