Check it out, I got bored one day and I decided to open some girl even though I wasn't interest. This was a university classroom so people don't know each other and each of my classes run for 3 hours. So what happened was I fell asleep a few times and I was like FUCK IT I'm bored. This is what you do:
You take out a piece of paper and draw the tic-tac-toe onto the paper and lead by putting an X on the top left corner(Hopefully you learned how to win this simple game in grade school). There are several ways to go about from here:
Win - You can win the game and tease her about it. She will probably start a new game.
Draw - If she has a brain it will most likely end up at this conclusion, at which point you can connect your X's even if they don't connect to show your fun side and she will most likely copy you. Tease her as well.
Lose - Now I've personally never lost a game but if you do lose. You can easily begin with a sexual innuendo like "I'm better at other things

" or a simple "I let you win".
Keep in mind! NO TALKING, the professor is teaching so you may only talk during breaks or after class. You don't want to get kicked out for a girl. EVERYTHING AND I MEAN EVERYTHING IS DONE IN PAPER. You may use eye contact or body language and after 5 or 10 minutes whisper in her ear about how the teacher looks like "Frank Grimes" from the Simpsons. Other then that, you write on the paper whatever you want to say.
Doc also suggested playing footsies since she is right beside you. You can do this about 30 minutes into the interaction. This is great and if she goes "STOP PLAYING FOOTSIES WITH ME" You can smile and say... "That's not my foot

"
Feedback would be nice and if you want to modify it to your own style it would be even better. Good like using it to sarge girls.