Go to the nearest barbershop or hair salon and collect all the hair you can into a big plastic bag. If they question you, say it's for a school project, and if you don't get it done soon, your parents will beat you. Take the hair home and spread it out onto the kitchen table. Use Elmer's glue to paste it to your face like a mustache and beard. Use some of the gray hairs to make you look a little older.
Dress up like a man by putting on your best suit, a hat (a grown-up hat, not a ball cap), and carrying a leather briefcase. Go to the movies, pull out your wallet, and say:
1) "Good evening, my good man. Let me just get my grown-up money out of my wallet, next to my real credit cards."
2) "How about that rat race, huh?"
3) "The boss has been on my back about these reports, down at the office."
4) "Well, gotta go. I'll let you know if this movie is suitable for my children, aged 13 and 17, a boy and a girl. Her name is Caitlin; she plays LaCross at her school. My boy is named Ben. He's named after me; I'm Ben Senior. Well, it's sure been darn nice talking to you, young fella, ha ha!"
Okay, you're in. Go see the movie and have fun. Leave the disguise on, though, because the ushers might check the theater halfway through the show, and you don't wanna miss the part where Dr. Oculus reveals he's really the girl's father.
After the movie, walk right up to the ticket clerk, as bold as you please, rip off the beard, and say, "HA! YOU FOOL!" then run like hell.