What to do for my Girfriend's birthday?

I need some ideas of what to do for her birthday... I really want to show her a good time and make her feel special. I'm on a tight budget of about �50 and there's no way I can have a free house and be alone with her. My budget is so tight because I'm 16, I don't get EMA or have a part time job. Her birthday is next week, I really need help! Please, no trolling also.